Stanford’s Gravity Probe B confirms two Einstein theories
After 52 years of conceiving, testing and waiting, marked by scientific advances and disappointments, one of Stanford’s and NASA’s longest-running projects comes to a close with a greater understanding of the universe.
Stanford and NASA researchers have confirmed two predictions of Albert Einstein’s general theory of relativity, concluding one of the space agency’s longest-running projects.
Known as Gravity Probe B, the experiment used four ultra-precise gyroscopes housed in a satellite to measure two aspects of Einstein’s theory about gravity. The first is the geodetic effect, or the warping of space and time around a gravitational body. The second is frame-dragging, which is the amount a spinning object pulls space and time with it as it rotates.
After 52 years of conceiving, building, testing and waiting, the science satellite has determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, Gravity Probe B’s gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein’s general theory of relativity, the gyroscopes experienced measurable, minute changes in the direction of their spin as they were pulled by Earth’s gravity.
The findings appear online in the journal Physical Review Letters.
“Imagine the Earth as if it were immersed in honey. As the planet rotated its axis and orbited the Sun, the honey around it would warp and swirl, and it’s the same with space and time,” said Francis Everitt, a Stanford physicist and principal investigator for Gravity Probe B.
A lasting legacy
“GP-B confirmed two of the most profound predictions of Einstein’s universe, having far-reaching implications across astrophysics research,” Everitt said. “Likewise, the decades of technological innovation behind the mission will have a lasting legacy on Earth and in space.”
Stanford has been NASA’s prime contractor for the mission and was responsible for the design and integration of the science instrument and for mission operations and data analysis.
Much of the technology needed to test Einstein’s theory had not yet been invented in 1959 when Leonard Schiff, head of Stanford’s physics department, and George E. Pugh of the Defense Department independently proposed to observe the precession of a gyroscope in an Earth-orbiting satellite with respect to a distant star. Toward that end, Schiff teamed up with Stanford colleagues William Fairbank and Robert Cannon and subsequently, in 1962, recruited Everitt.
NASA came on board in 1963 with the initial funding to develop a relativity gyroscope experiment. Forty-one years later, the satellite was launched into orbit about 400 miles above Earth.
The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed.
Despite the setback, Gravity Probe B’s decades of development led to groundbreaking technologies to control environmental disturbances on spacecraft, such as aerodynamic drag, magnetic fields and thermal variations. The mission’s star tracker and gyroscopes were the most precise ever designed and produced.
Played a role in developing GPS
Innovations enabled by GP-B have been used in the Global Positioning System, such as carrier-phase differential GPS, with its precision positioning that can allow an airplane to land unaided. Additional GP-B technologies were applied to NASA’s Cosmic Background Explorer mission, which determined the universe’s background radiation. That measurement is the underpinning of the “big bang theory” and led to the Nobel Prize for NASA’s John Mather.
“The mission results will have a long-term impact on the work of theoretical physicists for years to come,” said Bill Danchi, senior astrophysicist and program scientist at NASA Headquarters in Washington. “Every future challenge to Einstein’s theories of general relativity will have to seek more precise measurements than the remarkable work GP-B accomplished.”
Over the course of its mission, GP-B advanced the frontiers of knowledge and provided a practical training ground for 100 doctoral students and 15 master’s degree candidates at universities across the United States. Over 350 undergraduates and more than four dozen high school students also worked on the project, alongside leading scientists and aerospace engineers from industry and government.
Sally Ride, the first American female astronaut in space, worked on GP-B while studying at Stanford. Another was Nobel Laureate Eric Cornell, who also studied at Stanford.
NASA’s Marshall Space Flight Center in Huntsville, Ala., managed the Gravity Probe-B program for the agency. Lockheed Martin Corporation of Huntsville designed, integrated and tested the space vehicle and some of its major payload components.
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Learn a lot more on testing Einstein’s theories here h/t Dr. Leif Svalgaard via email
Simply amazing! At least someone is still doing real science.
So, spacetime behaves a litle bit like honey? Why don’t we just call it ether?
Wonderful post, Anthony. By the way, Aristotle’s vision of what he called the universe was very similar to the following:
‘“Imagine the Earth as if it were immersed in honey. As the planet rotated its axis and orbited the Sun, the honey around it would warp and swirl, and it’s the same with space and time,” said Francis Everitt, a Stanford physicist and principal investigator for Gravity Probe B.’
Oh, by the way, can someone recommend the ideal GPS device for hiking in and around the Appalachian Trail in Virginia?
Einstein.
A dude.
What would Einstein have said about “scientists” who hide their data even from Freedom Of Information laws? On consensus, he said: It doesn’t take 100 signatures to prove I’m wrong. It just takes one experimental fact.
There are only two nasty little problems to consider before you all get excited. First of all, time cannot change by definition and, therefore, nothing can move in spacetime. This is the reason that the great Sir Karl Popper called spacetime, “Einstein’s block universe in which nothing happens.” (source: Conjectures and Refutations).
Second, it is easy to prove that space (distance) is nothing but an illusion of perception). Surprise!
So these experiments did not prove that Einstein was right (he believed in the physical existence of a spacetime and of a time dimension!). They only proved that some of his equations were right. The interpretations of those equations, however, leave a lot to be desired.
It’s true. GPS satellites are effected by relativity, mainly the relativistic time slowing effect due to the speed of the satellites.
http://www.metaresearch.org/cosmology/gps-relativity.asp
Cool stuff, even if the physics gets a bit deep. 🙂
I joined the staff at Stanford in 1975. Shortly thereafter, I became aware of a program that was referred to in the bureaucratese of the day as Fairbanks, Everett and DeBra or GP-B. They were Bill Fairbanks from the Physics Department, Dan DeBra from Aero and Astro and Francis Everett from the Hansen High Energy Physics Lab. They soldiered on through periods where funding was not easy to raise and challenges as to the importance of the project were periodically raised. The many successes that came about because of their work is yet another testimony to the importance of funding basic research. Bill Fairbank died in the late 1980’s while on his daily run if I remember correctly but it is great that Francis Everett and Dan DeBra were able to see the fruition of decades of world-class work.
It is sad to see the amount of research monies that are being squandered on so much of what passes as science in the climate arena today.
Those are some interesting articles Leif. The reference frame dragging was one of hardest concepts to grasp, for me anyway.
It sure seems like NASA could hire an artist that knew the basics of gravity for a story about… gravity. Neat picture but somewhat misleading if you take it too literally! Don’t look at that green-blue mesh and think that is what the real signature of Earth’s gravitational field would actually look like, well, kind of, but not correct.
At the center of the Earth there is no gravity field, zero. There should be an upside-down V-shaped dimple pointing upward in the middle from the surface inward on that grid at it’s deepest point. Maybe that article will cause some here that might not realize that fact to ‘open the books’, so to speak, and be a bit more enlightened.
Another thing I learned not too long ago is that if the Earth’s density was constant then that upside-down dimple of the gravitational field from the surface to the center of the Earth would be linear, a straight line, and not an inverse squared curve.
That bothers me.
Darn! Einstein is right again. That sucks… we will never be able to travel faster than light… at least in this space-time continuum.
Gives me a bit of comfort as there still non grant grabbing ,AGW screaming ,
real scientists out there..
“The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed…”
Did they use Mannian PCA? It’s very good for finding signals that you know are there.
I’d like to know what was the unexpected wobble was caused by. If there was muddy data as a result, that took years to sort, what guarantee is there that cherry picking has not occurred?
I don’t get why the warping of space time is depicted as occurring on a single plane. Is this for illustration purposes only? I would have thought a large body bends space time in every direction.
I still don’t see how you can drag space. I can see gravity warping space (can I?) but I don’t get why spinning drags it. It’s as if we have the luminous aether again.
Awesome awesome science. And what an effort. Shame that AGW money is being pulled out of their funding pie.
I am a degreed physical scientist who will readily admit I have read Einstein thoroughly and proudly comprehend a little bit of it.
From NASA: “According to calculations, the twisted space-time around Earth should cause the axes of the gyros to drift merely 0.041 arcseconds over a year. An arcsecond is 1/3600th of a degree. To measure this angle reasonably well, GP-B needed a fantastic precision of 0.0005 arcseconds. It’s like measuring the thickness of a sheet of paper held edge-on 100 miles away.
Pulling off the experiment was an exceptional challenge. But after a year of data-taking and nearly five years of analysis, the GP-B scientists appear to have done it.
“We measured a geodetic precession of 6.600 plus or minus 0.017 arcseconds and a frame dragging effect of 0.039 plus or minus 0.007 arcseconds,” says Everitt.”
I am glad they were able to sift through the “problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data.” Good thing the scientists were able to take…”years to sift through the muddy data and salvage the information they needed.”
“Imagine the Earth as if it were immersed in honey. As the planet rotated its axis and orbited the Sun, the honey around it would warp and swirl, and it’s the same with space and time,”
Does anybody have a reference that discusses this “honey swirling” effect for the atmosphere? TIA
More from NASA: “Time and space, according to Einstein’s theories of relativity, are woven together, forming a four-dimensional fabric called “space-time.” The mass of Earth dimples this fabric, much like a heavy person sitting in the middle of a trampoline. Gravity, says Einstein, is simply the motion of objects following the curvaceous lines of the dimple.”
That is a handy image, using gravity to illustrate…gravity. 😀
Should Warmists pay any heed to Einstein’s sayings?
RayG says:
May 4, 2011 at 4:15 pm
“They soldiered on through periods where funding was not easy to raise and challenges as to the importance of the project were periodically raised.”
Old School Scientists. The science was what motivated them. No doubt they made significant personal sacrifices to practice their science. God Bless them and all like them.
xion III says:
May 4, 2011 at 4:43 pm
“I’d like to know what was the unexpected wobble was caused by. If there was muddy data as a result, that took years to sort, what guarantee is there that cherry picking has not occurred?”
There is no guarantee. However, the huge difference between this case and that of Climategaters is that these physicists had physical hypotheses (a huge set of them) that actually specify the data. Climategaters have no physical hypotheses at all, except the few they borrowed from poor old Arrhenius. Michael Mann has never created a physical hypothesis. All he has done is organize proxy data. That kind of fundamental science has to be done, but the very fact that Mann can be tenured and honored as a scientist-without-portfolio drives me up the wall.
The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data.
The mission’s star tracker and gyroscopes were the most precise ever designed and produced.
I’m having difficulty reconciling these two statements.
To warp space and time or to perceive space and time getting “warped”. O_0
Now, THAT’S how NASA should spend precious money (vs. Gavin’s budget?)!!
Nice stuff, thanks for posting!
On an Einstein tangent, Fermilab’s director, Dr. Pier Oddone, was just elected to the National Academy of Sciences, joining past luminaries including Einstein. This is an incredible honor and well deserved.
Pier’s an excellent chap and runs a great ship at Fermilab, wish him the best!
http://fnal.gov/pub/today/
This is old news to anyone taht has studied Eastern Mysticism. Anyone interested should research ‘Akasa’ (sometimes called Akasha)
Good to know the old station wagon has finally caught up to an early 20th century scientist.
Can we put the pedal to the metal and get a base on the moon now, or does Obama have to stop and take a leak?
Its true. The AGW debacle has made me “skeptical” of certain types of scientific claims.
There were, perhaps honest, “errors” made by those professing AGW — simply because they’re human and humans tend to see what they expect to see. Still, the fallacies would have been easy to correct by a qualified, objective member of the team. That they were not, is an indictment of “Big Government Funded Science” — and the desire to keep the funds coming.
Now, I am hesitant to “believe” the above results (which are the result of a big government funded science project) without seeing the data in detail and, maybe, doing some of the math myself.
Sad it has come to this, but true. Fool me once, as they say.
Congrats to Dr Everitt and his team. To overcome the technical and engineering challenges is quite an achievement. With regard to the unexpected wobble, this is the kind of problem that earth-bound experimenters face, but the difference is that Everitt et al. could not fly up there and fix things. To get usable data, I assume that they first had to figure out the source(s) of the wobbles, and then, carefully correct for them. I am sure the paper will describe these things in detail. You can build the most sophisticated equipment, but then you put it on a devise that does a controlled explosion to shoot it into space (Ouch!). I am amazed that anything to works properly.
There are some other interesting tests of GR. The Harvard Physics department has a video by Robert Pound called “Weighing Photons — The Story of an Experiment” from 1991.
http://www.physics.harvard.edu/about/video.html
You will find it on the main page with other interesting lectures (Sydney Coleman’s “Quantum mechanics in your face” is especially enjoyable)
— I love the internet!
Kudos to the physics community for putting cutting edge science from colloquia/seminars/meetings on the web. I only wish that other disciplines and departments follow suit.
Louis Savain says:
May 4, 2011 at 4:03 pm
There are only two nasty little problems to consider before you all get excited. […] They only proved that some of his equations were right. The interpretations of those equations, however, leave a lot to be desired.
I also noted in my email, that this was bound to stir up some General Relativity Deniers. BTW, General relativity is described by just one equation.
Interestingly, these results are still valid even if time actually is NOT a fourth dimension as it is so often thought of. This was a concept that Einstein actually embraced, as he saw time really as nothing more than the ordering of events, but the popular view of time as a actual fourth dimension has proven hard to shake. This article makes an excellent overview of this:
http://www.physorg.com/news/2011-04-scientists-spacetime-dimension.html
Neither the geodetic effect nor frame dragging actually require time as an actual dimension as they are effects on the 3D fabric of space caused by gravitational fields.
Svalgaard wrote:
I also noted in my email, that this was bound to stir up some General Relativity Deniers. BTW, General relativity is described by just one equation.
Leif, are you denying that time cannot change by definition and that, as a result, there can be no motion in spacetime? If so, let us see your explanation of how time can change. On second thought, don’t bother. I know you have no explanation.
In the meantime, let me explain to the rest of us why time cannot change. A change in position implies a velocity (rate of change) that is expressed as v = dx/dt. A change in time also implies a rate of change which is given as dt/dt, which is, of course, nonsense.
It is that simple, folks. This is the reason that there can be no time dimension, Einstein and a billion relativists claim otherwise notwithstanding. But don’t take my word for it. And don’t take the relativist’s word either. Do your own thinking. Figure it out on your own.
In a way. I expect a comment from Lubos
I love science…
/sighs happily
(even when it’s being done at Stanford, booooo)
Kudos to the researchers who soldiered on through the decades that it took to build, launch and then evaluate this mission.
It is too bad that the error levels of the results are so wide. They appear to encompass the expected values, so the results are consistent with expectations.
Ideally the results would have shown a discrepancy, something to spur new efforts to improve our understanding.
Is that the ‘missing mass’? The gravity of a galaxy wrapping up space around it as it spins?
Now that brings up another question:
If the spin of the Galaxy is wrapping up space around it and dragging it, where does the energy to continue spinning come from (resisting the friction)?
I want to say Dark Energy keeps the Galaxies from slowing down, but now I’m in over my head in honey.
So it seems that I too am of a skeptical disposition.
This was a hughly expensive experiment, consuming imense amounts of scarse resources.
Just what did it demonstrate?
Does it show anything more than moving a body through a gravitational field will influence the movement of that body?
Warped time? Warped space?
Just what is time made of?
What are the constitutes of space?
Pretty artifacts of complex equations.
Anything more?
Just what is time made of?
You cannot warp nothing.
So time must have a physical constitution.
Or Einstein was still mired in 19th century mysticism.
Do you want some “ether” with your fries?
I’ll take mine plain, thank you very much.
“Darn! Einstein is right again. That sucks… we will never be able to travel faster than light… at least in this space-time continuum.”
That only applies to the observer. According to Einstein, a spaceship with a constant 1 G acceleration can travel to the edge of the visible universe. 13 billion light years and the occupants of the space ship will only age about 60 years.
From the point of view of the folks onboard the spaceship, they have travelled much faster than light. Much. However, the folks back on earth will have aged a little bit more than 13 billion years during this time, so it will appear to them that you never exceeded the speed of light.
So, except for the problem of generating enough energy to maintain 1 G acceleration, human beings have the ability to visit anywhere in the universe within 1 lifetime.
Louis Savain says:
May 4, 2011 at 7:52 pm
Leif, are you denying that time cannot change by definition and that, as a result, there can be no motion in spacetime?
Yes, I’m a time-cannot-change denier. This experiment was called Gravity Probe B, because there was a Gravity Probe A long ago. In GP-A one atomic clock was sent into space while two clocks remained on Earth. Relativity predicts that the one that was sent aloft would run slower than the two on the ground, and sure enough it did, and by just the amount predicted. http://en.wikipedia.org/wiki/Gravity_Probe_A
End of discussion.
Louis Savain;
In the meantime, let me explain to the rest of us why time cannot change.>>>
Is there some genetic mutation out there that compels people to spew nonsense spattered with some randomly chosen math symbols related to nothing at all, just dribbled in a row in the paragraph? Is there some specific gene that makes people spew such drivel despite experimental evidence confirming the theory? One of the very first experiments NASA did in this regard was to put highly accurate atomic clocks in orbit in order to compare how they travelled in time compared to identical clocks on earth surface. The difference confirmed Einstein. Sorry Louis, but that was decades ago, and there have been more experiments since then, and they keep on confirming Einstein. Either he got it right or there have been an awfull lot of experiments that just coincidentally produced results matching Einstein’s equations to a rediculous number of decimal places. What pleasure or value you get out of announcing that dt/dt disproves him is beyond me.
So, the flow of time depends on the presence or absence of a large mass in vicinity.
Why this is never taken into account when they talk about red shift?
Leif Svalgaard says:
May 4, 2011 at 9:23 pm
Relativity predicts that the one that was sent aloft would run slower than the two on the ground
Grrr, faster, of course. High gravity slows down time.
So Leif, if gravity continues to rise….will time stop?
Sounds like the next crisis. Eat less, lose mass, save time. 😉
““Imagine the Earth as if it were immersed in honey. As the planet rotated its axis and orbited the Sun, the honey around it would warp and swirl, and it’s the same with space and time,” said Francis Everitt, a Stanford physicist and principal investigator for Gravity Probe B.”
Or…
Stick with me here, this is going to be complicated.
Imagine the Earth as if it were surrounded by a gaseous cloud and a thin layer of liquid.
Well, I guess his description is way better than mine, it has fantasy going for it.
So, exactly how does this disprove the idea that space is really a medium through which everything moves?
Alexander Feht says:
May 4, 2011 at 9:27 pm
So, the flow of time depends on the presence or absence of a large mass in vicinity.
Why this is never taken into account when they talk about red shift?
It is: http://en.wikipedia.org/wiki/Gravitational_redshift
The cosmological red shift is something else, completely, and have nothing to do with time slowing, but with space expanding. Note that the galaxies are almost stationary in space and do not move away from us or each other. Space is just getting bigger.
My God, R. Gates actually said something that made sense to me, and that I agreed with. And he actually cited a piece that seemed a genuine observation! Has the world gone mad? /sarc and laughter
Anthony Watts says:
May 4, 2011 at 9:44 pm
So Leif, if gravity continues to rise….will time stop?
Yes, if you are falling into a black hole we would observe that your time [e.g. as shown on a clock dial carried with you and visible to us] will slow to a crawl and eventually stop. You, on the other hand, would not detect anything unusual, except that you’ll eventually be shredded to long skinny threads.
Sounds like the next crisis. Eat less, lose mass, save time. 😉
Anthony Watts says:
May 4, 2011 at 9:44 pm
So Leif, if gravity continues to rise….will time stop?
Sounds like the next crisis. Eat less, lose mass, save time. 😉
Skinny threads are what you’ll become…
http://en.wikipedia.org/wiki/Black_hole
It was my privilege to study under Robert Cannon and Dan DeBra many years ago. Both their knowledge and their passion inspired me.
I wonder what Lubos Motl thinks of this announcement. He was very dubious about the project not long ago…
http://motls.blogspot.com/2010/03/tamino-5-sigma-and-frame-dragging.html
I knew it!
I knew that that planet was hovering just metres above a giant solar spiderweb!
And people mocked me….
🙁
I asked:
Leif, are you denying that time cannot change by definition and that, as a result, there can be no motion in spacetime?
Leif Svalgaard replied:
Yes, I’m a time-cannot-change denier. This experiment was called Gravity Probe B, because there was a Gravity Probe A long ago. In GP-A one atomic clock was sent into space while two clocks remained on Earth. Relativity predicts that the one that was sent aloft would run slower than the two on the ground, and sure enough it did, and by just the amount predicted.
Wow. That’s a complete non-answer. Do you realize that you are confusing the observed motion of a ticking clock with changing time? Clocks do not measure changing time. They only measure static and abstract temporal intervals. Amazingly, even a few well-known relativists agree with me that time cannot change. Here is what professor Robert Geroch wrote about the possibility of motion/change in spacetime:
Source: Relativity from A to B by Dr. Robert Geroch, U. of Chicago
Of course, Geroch would never publicly extrapolate the consequences of what he wrote in his book about nothing changing in spacetime. Why? Because that would bring a quick end to his career, thanks to people like you. Luckily, I have no such fear. Leif, it’s obvious that you are a truth denier. But why am I not surprised?
End of discussion.
I don’t think so. The discussion has not even begun. Repeat the following 1000 times a day until it sinks in:
Time cannot change by definition.
Nothing can move in spacetime
davidmhoffer wrote:
What pleasure or value you get out of announcing that dt/dt disproves him is beyond me.
dt/dt proves via extremely simple logic (which apparently went over your head) that, contrary to the claims of Albert Einstein’s (and many others), there is no such thing as a time dimension. That is all. This is true whether or not you or Svalgaard or anybody else likes it. I must admit that I do get a sense of satisfaction from rubbing the scientific community’s nose in their own excrement. I can’t help it. It’s the rebel in me.
PS. I do note that Svalgaard studiously avoids the argument I posed. Which is to be expected.
The discussion of Monbiot’s essay at Judith Curry’s Climate Etc is also worth reading.
judithcurry.com/2011/05/04/monbiot-on-environmental-fixes/#more-3152
Assuming equal mass in all directions, at the centre of the earth, gravitational force would be equal in every direction, and give the impression of zero gravity. Two masses (the imaginary observer and the earth) must produce a force, even if those forces cancel.
Leif Svalgaard says:
May 4, 2011 at 9:38 pm
Time must run very slowly in a black hole, perhaps barely existing, unless there is some type of a limit to how strong gravity can become.
It’s been an old-fashioned, happy project. But the accuracy of the frame dragging has been an immense disappointment.
With the nearly 20-percent error of the final figure, they would barely prove, at the 5-sigma confidence level, that the effect was nonzero and had the right sign…
http://motls.blogspot.com/2011/05/gravity-probe-b-final-results-frame.html
At any rate, one can’t be certain about the power of new experimental gadgets before they’re really tried.
Yes Anthony, I assure you Lief is entirely correct.
The classical view, for which read Einstein, is that at the speed of light mass and gravity become infinite and time ceases to exist in that it does not pass. This creates certain theoretical paradoxes.
Fortunately light does not travel at the speed of light, its group velocity, its actual speed, is always less than its phase velocity, its theoretical speed.
This relationship between mass and speed is elegantly demonstrated in the cathode ray tube where electrons are accelerated at quite low voltages to speeds at which the increased energy of the electrons starts to show up as increased mass instead of increased speed. It is actually very difficult to accelerate an electron beyond about half the speed of light, it just gets massier instead of going faster.
Much the same limitations in a different form presumably occur close to the event horizons of black holes.
Kindest Regards
Louis Savain says:
May 4, 2011 at 10:18 pm
Time cannot change by definition.
Time is what a clock shows. A clock can be oscillations of an atom: “a second is the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium-133 atom”
David said it well:
davidmhoffer says:
May 4, 2011 at 9:26 pm
“Is there some genetic mutation out there that compels people to spew nonsense”
Keith Minto says:
May 4, 2011 at 10:49 pm
Two masses (the imaginary observer and the earth) must produce a force, even if those forces cancel.
Already Newton knew that the mass outside a spherical shell does not produce a gravitational field, only the mass within the sphere. At the center of the Earth, the radius [hence volume and mass] of that sphere is zero, hence no gravity.
rbateman says:
May 4, 2011 at 10:52 pm
Time must run very slowly in a black hole, perhaps barely existing, unless there is some type of a limit to how strong gravity can become.
There is probably a [quantum theoretical] limit, but time inside the event horizon does not run slowly for an observer there. It is the observer outside the horizon that sees the infalling clock slow down [as also shown by the light emitted getting redder and redder and dimmer and dimmer]
When will these physicists learn? They wasted decades of time and money designing. building and then sending a satellite into orbit just for an experiment. Don’t they know that that isn’t how you do science these days? How could you ever believe the results of an experiment like this? All they had to do was build a computer model and that’s all the proof they would have needed.
TerryS says:
May 5, 2011 at 12:06 am
All they had to do was build a computer model and that’s all the proof they would have needed.
You seem to have an over-inflated trust in computer models.
I wrote:
Time cannot change by definition
Leif Svalgaard replied:
Time is what a clock shows. A clock can be oscillations of an atom: “a second is the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium-133 atom”
Complete waste of time. 🙂 See ya around.
Leif Svalgaard writes: At the center of the Earth, the radius [hence volume and mass] of that sphere is zero, hence no gravity.
Any kid who knows his Don Rosa, knows that: http://en.wikipedia.org/wiki/The_Universal_Solvent_(comics)
😉
Re: Leif
*sigh* forgot the /sarc
Louis Savain,
time changes not with dt/dt but with dt/dx.
As with a couple of others here, I still don’t understand what this warping of space time actually is, how does the Earth warp the space time around it as per the diagram since it must be doing so in all directions, unless this is all based on an idea of a flat universe? The honey the Earth is spinning in must be a something, an ether or whatever, which is being pulled around a spinning Earth ‘equally’ in a zero warp field, so there’s no warping only Earth spinning in something. And gravity then what? Does a spinning object attract or repel stuff around it?
In other words, can someone explain this in 3D before invoking a fourth dimension.
>>
Leif Svalgaard says:
May 4, 2011 at 11:58 pm
Already Newton knew that the mass outside a spherical shell does not produce a gravitational field, only the mass within the sphere. At the center of the Earth, the radius [hence volume and mass] of that sphere is zero, hence no gravity.
<<
Your statement is somewhat confusing (mine may be no better). A uniform sphere (constant density throughout) creates a normal gravity field outside (as if the mass was concentrated at its center-of-mass). However, everywhere inside the sphere, the gravitational force would be zero. As you (mathematically) move towards the center of the Earth, the outside mass sphere contributes no gravity force. The inside sphere is smaller and smaller and represents less and less enclosed mass.
This works for any inverse square law. The electric charge also follows the inverse square law and is why Von de Graaff generators work. The electric potential inside a metallic sphere is zero or at ground level. You can discharge a small potential charge to the inside of the metallic sphere, even though the total spherical charge may be several orders of magnitude larger.
It’s also why a Dyson sphere enclosing a star can’t orbit that star –there’s no inside gravity field for the star’s gravity to act on.
It’s harder to show mathematically, but a ring can’t orbit around a star either (as in Ringworld).
Jim
Leif Svalgaard says:
May 4, 2011 at 9:23 pm
Relativity predicts that the one that was sent aloft would run slower than the two on the ground
Grrr, faster, of course. High gravity slows down time.
Everything is relative….
A “brick” falls through the air faster than a “brick” sinks in water…
=> Gravity is a conceptual constant.
=> Gravity measurements are not absolute.
A “clock” ticks faster in space than a “clock” ticks on earth…
=> Time is a conceptual constant
=> Time measurements are not absolute.
the gyroscopes experienced measurable, minute changes in the direction of their spin as they were pulled by Earth’s gravity.
Well there is a surprise… opens eyes… rolls eyes.
>>
Louis Savain says:
May 4, 2011 at 10:30 pm
dt/dt proves via extremely simple logic (which apparently went over your head) that, contrary to the claims of Albert Einstein’s (and many others), there is no such thing as a time dimension. That is all. This is true whether or not you or Svalgaard or anybody else likes it. I must admit that I do get a sense of satisfaction from rubbing the scientific community’s nose in their own excrement. I can’t help it. It’s the rebel in me.
PS. I do note that Svalgaard studiously avoids the argument I posed. Which is to be expected.
<<
Since you think that Relativity is incorrect, then you must believe that our physics is only valid for the Earth. If we were to travel to another, distant galaxy, then their physics would be different?
Relativity is an old idea. It dates back to Galileo. It’s the idea that our physics is invariant with respect to reference frame. Newton’s three laws of motion are invariant under Newtonian-Galilean Relativity. Special Relativity makes Maxwell’s equations invariant with respect to inertial frames. General Relativity includes Special Relativity and makes Newton’s gravitation law invariant. General Relativity also includes both accelerating and non-accelerating frames of reference (among other things).
Most people who disagree with Einstein’s Relativity actually agree with the principles of Relativity. They just don’t like how the math works out.
Jim
Young Albert was a very smart guy.
Keith Minto says:
May 4, 2011 at 10:49 pm
Assuming equal mass in all directions, at the centre of the earth, gravitational force would be equal in every direction, and give the impression of zero gravity. Two masses (the imaginary observer and the earth) must produce a force, even if those forces cancel.
There you go, that’s a more proper definition. That has often made me wonder, since all matter resists compression, just where would the highest density inside the Earth occur? The center? Or at some distance toward the surface? Ahhh.. gravity, real strange effects sometimes.
Rabe says:
Louis Savain,
time changes not with dt/dt but with dt/dx.
Wow. I’ve never heard this one before. In physics, the only accepted evolution parameter is t. Sorry. Besides, if moving along the time dimension were possible, it would not require motion in any of the spatial dimensions.
But then again, you knew this. So why even write a comment?
Here’s another strange gravitational effect if curious:
Take a spacecraft approaching the asteroid belt, density evenly spread, and approaching in it’s plane. As you get nearer you would at first think you would be accelerating toward the approaching asteroids in front as they become visible.
Not so, when inside the orbit of the asteroid belt you would not feel it’s gravity at all. But, the minute you cross the belt’s boundary, if you make it across :-), you would immediately undergo a deceleration from the entire asteroid belt’s mass with its center of attraction near the sun. This deceleration would of course decrease at the inverse of the square of the distance, not from the nearby asteroids, but from the center of attraction near the sun.
That’s also a bit anti-intuitive. (and probably no, surely all of the physicists investigating the Pioneer’s anomaly took this strange effect into account (or did they? ☺))
Myrrh wrote:
In other words, can someone explain this in 3D before invoking a fourth dimension.
You’re wasting your time expecting an explanation that makes any sense from the relativist community. There are no people in physics more clueless than relativists. They understand absolutely nothing. They only confuse the hell out of everybody. They certainly have no clue as to why things fall. All that spacetime curvature nonsense is just that, nonsense.
Louis Savin – I’m not the only one here wondering about it. Are you saying we’re not going to get an explanation for this very simple basic question?
Einstein may have an equation that or two that work but they tell us nothing and prove nothing. Lorentz.s relativity has a different and easily understood concept and the Lorentz transformation are a law of nature using matter mechanics. They will lead to physics beyond relativity. This experiment with perfect balls is easily explained but with a different conclusion. When science or engineering require ever more complications and parts, often imaginary, to prove their theory they are marching in the wrong direction. The universe and indeed nature tends to the minimum for perfection.
“Stanford’s Gravity Probe B confirms two Einstein theories”
Oh dear. You can’t prove a scientific theory. What you can do is verify predictions based on that theory. Which is what the article states in the second para – “Stanford and NASA researchers have confirmed two predictions….”
New sub-editor needed .
Beautiful. I first became interested in science around 8 years of age, and this is precisely the sort of science that fascinated me back then. This is real science, and the climate science community could learn much from it if they were willing too do so.
I.e. Theory vs Empirical tests. Not Theory tested via theoretical computer models
When I first heard of the concept and required technology for this experiment I was stunned by their audacity-fantastic! Last year another of Einstein’s predictions- that while the speed of light was constant that at very short wavelengths- 10 to the -23 and -24 power cms there would be variations. Last year the radiation ? from implosion of an early galaxy arrived at Earth after about 13 billion years of travel. The two different wavelengths arrived 11 minutes apart as Einstein predicted. It was described in “Sky and Telescope” magazine. It leaves for dead all the the kindergarden climate science. I read Einstein mathematics for fun and my IQ measured in school sixty years ago was in his ballpark but I just cannot grasp how he imagined the concepts he did let alone convert them to exacting mathematics. To hurl a bunch of super gyroscopes to swirl through gravity waves while focussing on a distant star-how wonderful that real scientists of genius quality still exist. In spellbound admiration. Geoff Broadbent
Jim Masterson, sorry, noticed I basically doubled your comment earlier. Oops. Well, at least it’s a bit different. ☺
Was Einstein the true author of ‘Einstein’ theories?
‘The Annus Mirabilis papers are four articles pertaining to the photoelectric effect (which gave rise to quantum theory), Brownian motion, the special theory of relativity, and E = mc2, that Albert Einstein published in the Annalen der Physik scientific journal in 1905. These four works contributed substantially to the foundation of modern physics and changed views on space, time, and matter.’
His four most important papers were submitted for publishing on March 18 (he was only 26 two days earlier), May 11, June 30 and September 27 in year 1905.
It can be assumed that he worked on papers for at least some months earlier.
Incredible success for 24-5 year old; 4 years earlier at ETH Zurich ‘Although the final grades for Einstein fell below the 5 point average that was necessary to pass, Einstein’s 4.9 was rounded up to a 5, so he squeaked by’.
Einstein’s future wife, Mileva Marić (she was 4 years his senior), also enrolled at the Polytechnic that same year, the only woman among the six students in the mathematics and physics section of the teaching diploma course. Over the next few years, Einstein and Maric friendship developed into romance, and they read books together on extra-curricular physics in which Einstein was taking an increasing interest..
Mileva was deeply in love with Einstein, not very attractive and lame, in late January 1902 she gave birth to his illegitimate daughter called Lieserl. Albert and Mileva were married exactly one year later at Bern City Hall on January 6, 1903. She was just 28 Einstein was almost 24.
1905 was Einstein’s annus mirabilis, the miracle year. Albert published his four scientific papers that each marked an important breakthrough.
Mileva told a Serbian friend, “we finished some important work that will make my husband world famous.”
They were divorced in 1919, Albert was world-famous figure, but he never again produced physics on a par with the work of 1905.
How come this 24 year old genius that revolutionised physics, for five decades to follow produced very little in comparison?
Also Einstein agreed to sign over to Maric any future Nobel Prize money as part of the divorce settlement! Not money or property now, but ‘any future Nobel Prize money’, the result of the scientific achievements! Odd that.
Maric never made any claims, but content of her letter is telling:
’ But what can be done, one person gets the pearl and the other just gets the shell’.
2 words : “optical gyro”
Louis Savain says: (May 5, 2011 at 12:30 am)
I clicked on your link “Complete waste of time”
You are correct, it was a complete waste of my time.
ferd berple:
I have been accellerated for almost exactly 60 years at 1g now.
As my wife would put it, I am unfortunately still here and not at all near the end of the universe .
I will admit that my mass has increased, but not by relativistic amounts. The wife would argue that point, though.
Einstein was wrong on so many levels, it seems.
Ray says:
May 4, 2011 at 4:30 pm
Darn! Einstein is right again. That sucks… we will never be able to travel faster than light… at least in this space-time continuum.
Nothing can travel faster than light. So Ray if you turn into nothing you can travel faster than light. Or turn into heat as heat travelled with the edge of the universe as it expanded faster than light. Take your pick.
Jim Masterson says:
May 5, 2011 at 1:23 am
Your statement is somewhat confusing (mine may be no better). A uniform sphere (constant density throughout) creates a normal gravity field outside (as if the mass was concentrated at its center-of-mass). However, everywhere inside the sphere, the gravitational force would be zero.
You are correct that yours is no better. The density does not have to be constant, just only depending on distance from the center. And the field is not zero everywhere inside the sphere. If you substitute ‘spherical shell’ for ‘sphere’ your statement becomes correct.
On a more interesting note, one can ask where within the Earth gravity is the strongest? If you drill into the Earth and descent towards the center, gravity actually increases at first. [left to the student to explain why].
Tom in Florida says:
May 5, 2011 at 5:41 am
I clicked on your link [Louis Savain:] “Complete waste of time”
You are correct, it was a complete waste of my time.
Except it was an illuminating study of human stupidity
Louis Savain:
I have read all your posts and – with the exception of your offensive remarks at May 5, 2011 at 3:01 am – I admit that I have failed to make sense of any of them. So, I present my own understanding in hope that you will explain to me where you think it is wrong. My undertanding is as follows.
1.
Relativistic Theory says everything exists in the space-time continuum.
2.
The space-time continuum is an unchanging state that can be represented mathematically as being like a surface (with shape similar to a riding saddle).
3.
According to Relativistic Theory, a passage of time is described as being a movement from one place on the surface to another.
4.
According to Relativistc Theory, a movement in space is described as being a change from one place on the surface to another.
5.
The Relativistic Theory of the space-time continuum provides demonstrably correct predictions which indicates that it is correct.
6.
The unchanging state of the space time continuum is not consistent with Quantum Mechanics which presupposes that all possibilities co-exist until one of them becomes a reality.
7.
The theory of Quantum Mechanics provides demonstrably correct predictions which indicates that it is correct.
8.
Points 5 and 7 are not consistent because of point 6 (and this inconsistency is why Einstein refused to accept Quantum Mechanics).
9.
Relativistic Theory describes the overall behaviour of the universe throughout its existence while the theory of Quantum Mechanics describes behaviours of the smallest parts of the universe.
9.
A Grand Theory Of Everything would reconcile Relativistic Theory with Quantum Mechanics and, thus, provide a description of the universe at all scales.
10.
Some people who believe in ‘free will’ have difficulty with the concept of the space-time continuum because that concept implies all actions are fixed and, therefore, no person can choose an action (this disagrees with the ‘feeling’ that we do choose between possible actions).
11.
I believe in ‘free will’ (I am an Accredited Methodist Preacher) but – like most others who believe in ‘free will’ – I have no difficulty accepting that Relativistic Theory is ‘true’.
12.
Our best descriptions of the universe are defined by empirical data and the ability of those description to make accurate predictions, so there is no reason to suppose that our best descriptions of the universe have to agree with our personal experiences.
13.
Unless and until the Grand Theory Of Everything is developed then considerations of ‘free will’ are not relevant – and cannot be relevant – to scientific descriptions of the universe at any scale.
OK. That is an itemised statement of my understanding of the matter. Please tell me what you think is wrong with my understanding.
Richard
ferd berple;
On a more serious note;
If time, as Einstein suggests, does not exist but is only a succession of events, the succession of events like passenger metabolism, nuclear decay etc, will happen at the same rate aboard the space ship as on the earth.
Lorentz transformation of light emitted from the space ship to earth will make the space ship appear to travel slightly below c as seen from earth. As seen from the space ship, it will be steadily accellerating and will within a year reach c if accellerated at 1g.
After travelling to the end of the universe in 60 years and back in another 60 years (assuming the travellers will stop for a look at the view) the metabolism and nuclear decay on board will have seen 120 years as will the people on earth.
The big problem is to find a propellant that will allow such travel.
Dan says:
May 5, 2011 at 6:41 am
I have been accellerated for almost exactly 60 years at 1g now.
As my wife would put it, I am unfortunately still here and not at all near the end of the universe .
But in the wrong direction 🙂
@ Louis Savain:
That sounds a lot like the ‘ol “what happens at the edge of the universe” problem.
If you’re standing at the edge of the universe, and stick out your hand, where does it go?
“an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed.”
Ah,
Hmmm.
Leif Svalgaard says:
May 5, 2011 at 6:58 am
On a more interesting note, one can ask where within the Earth gravity is the strongest? If you drill into the Earth and descent towards the center, gravity actually increases at first. [left to the student to explain why].
Increase in density. Subcrustal matter is denser and so the intrepid terranaut is closer to a stronger source of gravitation than at the surface soon after (s)he starts the descent. Gravitation falls off with the square of the distance, so the pull is stronger when the distance to the denser material is less.
Louis,
“There are other equally irrefutable proofs of the non-existence of space but the one above is sufficient.”
Sure, I’m going to accept the word on whether an explaination is sufficient from the guy “debunking” Einstein by merely claiming that he doesn’t like it. 🙂 (ie. “infinite regression”.) That’s a philosophical arguement, not a scientific one.
As a matter of fact, the regression isn’t a given. One article I’d read a year or two ago suggested that space time is like a web mesh. Each joint of the net is a “point” in space that something can occupy. These “points” can be stretched and compressed toward and away from each other, however. This “distance” is basically an energy.
This is a rather elegant framework and helps to understand things like the attenuation of gravity over distance. Rather than imagining that every piece of matter interacts with every other piece of matter in the universe, instead one could imagine that that matter warps its mesh and the points adjacent to its mesh. Those adjacent points modify THEIR adjacent points, etc, etc, ad infinitum, to lesser and lesser effect as you propogate away from the initial disturbance.
Lief:
Is it possible to expand space without expanding time?? … or conversely, can space contract without contracting time?
What happens to all these questions if we simply give the universe, a velocity, which induces apparent mass (hence gravity) into everything? I wish I had answers, that I could hang my hat on. GK
Mark Wagner says:
May 5, 2011 at 7:22 am
If you’re standing at the edge of the universe, and stick out your hand, where does it go?
Mark, I think the answer is that your hand just keeps reaching out. In other words, you can never catch up with the “edge” of the expanding Universe.
Leif,
I guess in order to ‘rescue the data’ the scientists must have found some systematic ‘aberrations’ in the gyroscope headings. Have they documented those and found satisfactory explanations for them?
tallbloke says:
May 5, 2011 at 8:04 am
I guess in order to ‘rescue the data’ the scientists must have found some systematic ‘aberrations’ in the gyroscope headings. Have they documented those and found satisfactory explanations for them?
In order to interpret the data you must first understand your instrument. Such understanding often comes after the experiment when unexpected effects show up. But, yes, they have documented this and, more importantly, understand why they occurred. This is part of the reason it took so long. Their result is rock solid. It is every scientists dream to prove Einstein wrong, so much of their analysis was fueled by this dream. As usual, Einstein came out right.
G. Karst:
At May 5, 2011 at 7:48 am you ask Lief:
“What happens to all these questions if we simply give the universe, a velocity, … ?”
I ask, a velocity of the universe relative to what?
Richard
G. Karst says:
May 5, 2011 at 7:48 am
Is it possible to expand space without expanding time?? … or conversely, can space contract without contracting time?
Time does not ‘expand’, just rolls on. It is important to keep the notion of ‘expanding space’ clear of confusing elements. Nothing can move through space faster than light, but space itself can expand [and does] at any speed. Some of the farthest galaxies found have a red shift in excess of 10 http://cosmiclog.msnbc.msn.com/_news/2011/01/26/5920882-hubble-spots-farthest-galaxy-again which if the galaxy was moving through space would amount to 10 times light-speed. But the galaxy is not moving through space and time in that galaxy has not been distorted. Space has just expanded. The cosmic microwave radiation has a red shift of 1089 [one thousand eighty-nine], meaning that space has expanded by that factor since the radiation was emitted, some 379,000 years after the Big Bang. What we see is radiation emitted at a temperature of about 3000K, and which [wavelength] has been stretched by the expansion, so that it now is 1089 times longer, corresponding to a temperature of 2.725K.
Louis Savain says:
May 4, 2011 at 10:30 pm
dt/dt proves via extremely simple logic (which apparently went over your head) that, contrary to the claims of Albert Einstein’s (and many others), there is no such thing as a time dimension. That is all. This is true whether or not you or Svalgaard or anybody else likes it. I must admit that I do get a sense of satisfaction from rubbing the scientific community’s nose in their own excrement. I can’t help it. It’s the rebel in me.
According to your logic there is no such thing as a space dimension, since dx/dx and dy/dy and dz/dz are stable!
Think again.
Time is a measure of fourspace adjusted to human biology and mentality. In a science fiction scenario, one could describe “life” that evolved in what is for us the x direction while remaining well defined in t,y,z. When reaching a certain x, life would end. Whereas t,y and z could be explored and expanded into.
It is the change in the space variables that forces us to use time as time, and it is all due to the biology of the planet earth. IMO.
In “Light” of the confirmation of General Relativity, what would be the results of the following experiment?
Wrap an Optical Fiber around the equator of Earth. From Point A on the fiber, Send a laser pulse Eastward and Westward simultaneously. What will happen when the two pulses return to point A?
What will be the Time between the Arrival of the Westward pulse (arriving from the east) and the Eastward Pulse (from the west)?
A1. As measured by a clock at Point A.
A2. As measured by a clock a million miles from Earth in Earth’s solar orbit? (no Earth gravitational time dilation at the earth’s surface, but Solar gravitation and orbital speed the same.)
The Earth is a rotating gravitational Field,
and the fiber attached to the earth is in an accelerating frame of reference.
Assume Index of refraction is 1.62 or Speed in fiber is 200,000 km/sec. http://en.wikipedia.org/wiki/Optical_fiber#Index_of_refraction
Circumference of Earth: 40,075.16 kilometers, OK to use 40,000 km even.
Rotational speed of earth at the equator: 465.1 m/s
Let’s assume standard gravity at the equator (without centrifugal Acceleration) is 9.800 m/sec.
B. What happens if the light fiber is replaced by a mirror lined vacuum tube?
C. Is B the same thing as a light fiber (a solid medium attached to the rotating earth) with an index refraction of 1.00?
D. What happens if earth’s gravity acceleration is increased to 98 m/sec (x10)? (and the shape of the earth does not change)
If anyone has a link to pages that describe this experiment, I would greatly appreciate it. Does this experiment have a common name?
The answer to C above is NO. Light would not bend around the circle. You need the wave guide to trap the light into a circular path, and for that you need a core with an index of refraction >1.00.
Stephen Rasey says:
May 5, 2011 at 8:48 am
Wrap an Optical Fiber around the equator of Earth. From Point A on the fiber, Send a laser pulse Eastward and Westward simultaneously. What will happen when the two pulses return to point A?
The simplest way to think about this is to note that because of frame-dragging, the length of the path in the direction of the rotation will look to be about an inch shorter [IIRC]. “Under the Lense–Thirring effect, the frame of reference in which a clock ticks the fastest is one which is rotating around the object as viewed by a distant observer. This also means that light traveling in the direction of rotation of the object will move around the object faster than light moving against the rotation as seen by a distant observer.”
Again wikipedia has a good description: http://en.wikipedia.org/wiki/Frame-dragging
BarryW says:
May 4, 2011 at 4:27 pm
The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed.
That bothers me.
You’re not the only one that’s bothered by it. Seems to me they went looking for what they expected, after something unexpected occurred. Confirmation bias, possibly. ARGO data, anyone?
Another point: this is not “proof” or “confirmation” of a theory. The scientific method states that this was only a failure to falsify a prediction. Saying anything else is conjecture.
According to loop quantum gravity space itself has a Planck dimension. This makes one think of ether, however, space has no mass or energy but contains items that do. All makes for some very interesting thoughts.
An analogy might be a projection screen. The screen is real and has qualities but those do not influence the content of the picture being presented on the screen. The screen itself logically exists outside the picture.
Lief, I don’t know the answer to these questions in the fiber loop experiment. But I know there are several things going on.
In the 0.20 seconds it takes for the pulses to travel the fiber, Point A has moved Eastward by about 93 meters. So the Eastward path is 186 meters longer than the Westward path as viewed by Observer A2. So Eastward arrives about 0.93 microsec after Westward?
Or does the velocity of the fiber cancel out the extra distance? The fiber has moved eastward by 93 meters, too. Is the light’s speed added to the fiber’s speed? So that, neglecting frame dragging the points should arrive at the same time? Or at almost the same time (got to be some Lorentz contraction in there somewhere).
If so, then the results for Question B ought to be markedly different from Question A and not just by the difference in the refractive index. But then again, there are mirrored walls are also moving with the earth’s rotation, but I have a hard time adding the rotational speed of the vacuum tube guide to the speed of the wave form inside the guide. That observer A2 away from the earth will object. Yet Simultaneity I don’t think will be an out because all observations will be done at Point A or by a distant observer A2 looking at point A.
On top of all this, we still have to apply the affects of frame dragging where by the Eastward pulse should arrive slightly faster, not slower, than the Westward pulse, all other things being equal.
So, are you saying than in A1
R1: the Eastward pulse arrives (1 in = 0.02 meters = 0.1 nano sec) Earlier than the westward pulse,
R2: the Eastward pulse arrives (0.93 microsec = 930 nanosec) (930-0.1) nanosec LATER than the westward pulse.
Or something else?
Elftone says:
May 5, 2011 at 9:14 am
The scientific method states that this was only a failure to falsify a prediction. Saying anything else is conjecture.
If I predict that a major earthquake [or solar flare or whatever] will occur in three weeks from today at 12 GMT and it does happen, you would call that only a failure to falsify my prediction…
Richard S Courtney:
“I ask, a velocity of the universe relative to what?”
That does seem problematic, doesn’t it? One might say, it is traveling through the same place it expands into. That, however, assumes linear, straight line thinking. I would suggest spinning (velocity) is less problematic. No particle is born void of velocity. Why do we assume, the universe came out of the big bang, without velocity?? GK
Leif Svalgaard:
I think you confused my use of the word “universe” with “galaxy” , but thanks for the reply. GK
Stephen Rasey says:
May 5, 2011 at 10:00 am
I don’t know the answer to these questions in the fiber loop experiment. But I know there are several things going on.
There are special relativity effects that are much larger than the frame dragging. In addition the fiber bending complicates the analysis [which I’ll not attempt here – OT for one]. I don’t think we could measure frame dragging with your experiment. A sharp test of frame dragging will be possible in a few years: The supermassive black hole at the center of the Milky Way causes severe frame dragging of the stars that orbit the hole. Several such stars [at different distance to the center and therefore with different frame dragging] are monitored right now and perturbations of their orbits caused by frame dragging will soon [takes time to collect enough data for a good orbit determination] be apparent.
The universe expands. What is it expanding into?
Last night on “How the Universe Works” it was said that the laws of physics allow the creation of energy from nothing. They never said what law and how does that jive with the conversation of energy law (no matter/energy created or destroyed)?
What is the temperature on the surface of a super massive black hole?
BarryW:
I totally agree. Being in a 50 year project means there must be a lot of pressure to come up with something. People here tend to be much more cautious regarding data manipulation issues, when it comes to other topics.
Comment section should be re-titled Louis Savain’s Rant…
New ways of looking at the box are good, but I must say that after reading several articles on Louis Savain’s blog as well as many of his posts here… he seems to have based much of his rant on dt/dt and inconsistencies between quantum mechanics and relativity… But dt/dt is a non-starter for scientific discussions because time is constant in a reference frame… that’s the beauty of reference frames, time in one frame moves relative to relative to another reference frame… so dt/dt is a mistaken expression…
Louis Savain should instead look at dt (reference frame 1) / dt (reference frame 2) — it is easy to show that this is certainly not a constant… thus time does move…
And — the inconsistency between relativity and quantum mechanics has not stopped either from producing useful, testable, experimental results…
Leif Svalgaard says:
May 5, 2011 at 10:00 am
If I predict that a major earthquake [or solar flare or whatever] will occur in three weeks from today at 12 GMT and it does happen, you would call that only a failure to falsify my prediction…
Nope, I would not… and I would call you brilliant :).
My point, which was badly made by me, is that using the results of one prediction of one aspect of a theory does not confirm that theory. It merely means that, yet again the theory is holding up to some of the most rigorous testing ever, which means – in many respects – it is the best theory we have with which to work. It also means it was an amazing body of work, worthy of respect.
Do understand me: I have no problem or axe to grind with Einstein or his theories of special or general relativity. I do have a problem with inferences made that cannot be supported by the facts as reported. That’s all. Quite simple really.
Re: Rasey May 5, 2011 at 10:00 am
Is the light’s speed added to the fiber’s speed?
No. Otherwise Ring Laser Gyro’s and Fiber Optic Gyros would not work. http://en.wikipedia.org/wiki/Ring_laser_gyroscope
http://en.wikipedia.org/wiki/Fibre_optic_gyroscope
The thought experiment I put forth is equivalent to putting a Fiber Optic Gyro around the earth at the Equator. The Frame Drag is irrelevant in a typical Fiber Optic Gyro, but it matters when the FOG surrounds a rotating planetary mass.
Elftone says:
May 5, 2011 at 11:08 am
I do have a problem with inferences made that cannot be supported by the facts as reported.
The issue at hand is an inference supported by the experiment [‘facts’]. The inference was that yet another one of Einstein’s prediction has been borne out, confirming his theory. ‘Confirmation’ is just a ‘piece of evidence’. Forget about ‘proof’. No scientists use that word.
Leif Svalgaard says:
May 5, 2011 at 11:41 am
Forget about ‘proof’. No scientists use that word.
Completely agree!
Is no one giving me an explanation to my question because no one knows the answer?
Is Louis Savin right, that you don’t know?
http://wattsupwiththat.com/2011/05/04/einstein-proven-right-again/#comment-653506
This isn’t a trick question, it’s genuine, it’s something I’ve wanted to understand for a long time and I thought I would get an explanation here.
Whenever I’ve watched this diagramatic explanation on TV I’ve not been able to understand it. Once, someone said that it was applicable all the way round, 3d, and I thought that must be some very clever physics of time/space that I wasn’t grasping. However, it looks like you don’t have an answer. The 3rd dimension appears to have stumped you.
I have taken an interest in these things on and off, what I’ve managed to gather without having the maths language, but just to make it clear, nothing in the concepts of 20th century science is alien or surprising to me. In fact, I have found it a bit amusing that recently it’s been proposed that matter can go through other matter equally solid and be in two places at once, amused because these concepts have been around for milleniums and I seem to recall that not very long ago scientists were busy poo-pooing this kind of thinking..
Anyway, all I want to know is how this diagram above works in 3D. Because, to me it cancels itself out in 3D.
And after Savin’s reply to me, /#comment-643548, I thought of this: http://www.geom.uiuc.edu/~banchoff/Flatland/
I also thought I should wait to see if there was any answer before concluding, as I have tentatively, that it wasn’t my lack of intelligence, as I’d assumed, that made me think that the diagram and the explanation didn’t describe a three dimensional world and I couldn’t make it make sense in 3D, it was that the concept was nonsense in our physical three dimensional world.
But, before I go the whole hog here, would you Leif and all those who’ve made disparaging remarks about Louis Savin, please give me an explanation that makes sense in 3D reality.
If you can’t explain it, I would appreciate you saying so, I don’t want to keep hanging around in case you reply. If I don’t hear from you, I shall assume that Savin is right, you don’t know what you’re talking about. Because this is a very simple problem, it surely can’t be beyond your abilities to explain it.
“”””” wayne says:
May 4, 2011 at 4:23 pm
Those are some interesting articles Leif. The reference frame dragging was one of hardest concepts to grasp, for me anyway.
It sure seems like NASA could hire an artist that knew the basics of gravity for a story about… gravity. Neat picture but somewhat misleading if you take it too literally! Don’t look at that green-blue mesh and think that is what the real signature of Earth’s gravitational field would actually look like, well, kind of, but not correct.
At the center of the Earth there is no gravity field, zero. “””””
Somebody should quickly inform the sun, that it is having no effect at the centre of the earth’ probably because of all the magnetic shielding around that point. Oh I forgot, that all that iron would be above the curie Temperature.
But amazing that the earth can shiled the sun’s gravity.
I always thought gravity had an infinite range so that shielding is inherently impossible. Just think, if you could actually build an anti-gravity shield, then there would be no gravity on she shielded side, all the way out to infinity, and if you held it up, the entire atmosphere of the earth would rush into the shielded zone, and immediately escape to space; well at the velocity of sound anyway.
Leif Svalgaard says:
May 4, 2011 at 9:23 pm
Leif Svalgaard says:
May 4, 2011 at 9:23 pm
..Yes, I’m a time-cannot-change denier. This experiment was called Gravity Probe B, because there was a Gravity Probe A long ago. In GP-A one atomic clock was sent into space while two clocks remained on Earth. Relativity predicts that the one that was sent aloft would run slower than the two on the ground, and sure enough it did, and by just the amount predicted. http://en.wikipedia.org/wiki/Gravity_Probe_A
End of discussion.
~
Hmm Gravity Probe A
From the wiki
..The probe was launched on June 18, 1976 on top of a Scout rocket and remained in space for 1 hour and 55 minutes, as intended. It then crashed into the Atlantic Ocean.
..The satellite was launched nearly vertically upward to cause a large change in the local gravity seen by the maser, reaching a height of 10,000 km (6200 miles). At this height, general relativity predicted a clock should run 4.5 parts in 1010 faster than one on the Earth.
..The experiment was thus able to test the equivalence principle. Gravity Probe A confirmed the prediction that gravity slows the flow of time, and the observed effects matched the predicted effects to an accuracy of about 70 parts per million
http://en.wikipedia.org/wiki/Gravity_Probe_A
What was up with that wobble on B .. or did I miss something. And what did we do all those years with B?
Vuks..good show..goes to show..behind every great man.. is a great woman..
I love these debates. Love to read all the links everyone throws out and think about it.
One of my favorite quotes is by Einstein
“Now you think that I am looking back at my life’s work with calm satisfaction. But, on closer look, it is quite different. There is not a single concept of which I am convinced that it will stand firm and I am not sure if I was on the right track after all:”
Even with the whole world singing his praises he never quit trying to reconcile why his theories didn’t work to his satisfaction. Never stop trying to find holes in your work and explain them. That alone is his greatest achievement IMHO.
“”””” Louis Savain says:
May 4, 2011 at 10:30 pm
davidmhoffer wrote:
What pleasure or value you get out of announcing that dt/dt disproves him is beyond me.
dt/dt proves via extremely simple logic (which apparently went over your head) that, contrary to the claims of Albert Einstein’s (and many others), there is no such thing as a time dimension. “””””
Well if you want to get down to the ultimate in pedantry; there is no such thing as any of the things we talk about in Physics; or in mathematics. There is absolutely nothing in any branch of mathematics, that actually exists, and can be observed anywhere in the known or unknown universe. it is all a complete fiction, and we made it all up out of whole cloth in our heads.
We also made up all our theoretical models of Physics, and none of those things actually exist anywhere either.
But using our mathematical fictions, and the rules of manipulation we arbitrarily assigned to them, we can predict what our equally fictional models would do if we conducted a particular experiment on them.
We then let other folks know about our results, so they can go and examine the real universe and see, if they can observe any sort of analagous behavior in the real universe, to correspond to what our theories say our models would do.
So if you want to deny the existence of something; be sure to include all of the other things that don’t exist either. (except in our heads).
Myrrh says:
May 5, 2011 at 1:07 pm
Is no one giving me an explanation to my question because no one knows the answer?
The answer is long. Wikipedia has some good pointers: http://en.wikipedia.org/wiki/General_Relativity
Because this is a very simple problem, it surely can’t be beyond your abilities to explain it.
It may be beyond your ability to understand it. By that I mean, that there are fundamental issues about what curvature is and how to express it, and those are not easy to visualize, without resorting to somewhat misleading images [like the bowling ball on a membrane]. Start with the wiki. There are also good books on the subject [referenced in the wiki]
George E. Smith says:
May 5, 2011 at 1:18 pm
I always thought gravity had an infinite range so that shielding is inherently impossible.
The Earth is in free fall around the Sun and thus does not feel any gravity [except its own], just like an astronaut in free fall about the Earth.
Carla says:
May 5, 2011 at 1:22 pm
did I miss something. And what did we do all those years with B?
As usual, yes. We spent all those years developing the technology necessary for B to work.
DirkH says:
May 4, 2011 at 3:32 pm
So, spacetime behaves a litle bit like honey? Why don’t we just call it ether?
Because people would fall asleep.
BarryW says:
May 4, 2011 at 4:27 pm
That bothers me.
Bothers a bunch of people. Data-mining is even more environmentally unfriendly than gold mining with nukes and aerosolised mercury…
Leif Svalgaard says:
May 4, 2011 at 9:38 pm
Leif Svalgaard says:
May 4, 2011 at 9:23 pm
Relativity predicts that the one that was sent aloft would run slower than the two on the ground
Grrr, faster, of course. High gravity slows down time.
So, given this experiment ( http://www.ru.nl/hfml/research/levitation/diamagnetic/) does this mean the frog is operating in a quicker time to the rest of the room because it is weightless, or does it not count because it isn’t gravity? Would a steel ball bearing placed into the apperatus be operating in a slower time to everything else – because it most definitely would be having a force acting upon it.
If it doesn’t count as “anti-grav”, and I’m still subject to local time if I were to use such an apperatus to annul the gravitational field of a black hole, would I have a time gradient from head to toe, given I would no longer turn into silly string? Could I use such a time gradient to time travel?
Luboš Motl says:
May 4, 2011 at 11:43 pm
It’s been an old-fashioned, happy project. But the accuracy of the frame dragging has been an immense disappointment.
With the nearly 20-percent error of the final figure, they would barely prove, at the 5-sigma confidence level, that the effect was nonzero and had the right sign…
Become a climate scientist. Having the right sign isn’t important, and one sigma is enough. (Do I really have to put /sarc there?)
Leif Svalgaard says:
May 5, 2011 at 8:34 am
Nothing can move through space faster than light, but space itself can expand [and does] at any speed. Some of the farthest galaxies found have a red shift in excess of 10 http://cosmiclog.msnbc.msn.com/_news/2011/01/26/5920882-hubble-spots-farthest-galaxy-again which if the galaxy was moving through space would amount to 10 times light-speed.
So does this mean that light emitted past a certain point in the expansion of the distance between us and a star would never reach us because it would need to be faster than light to overcome the expanding? How would this look different from the rest of the universe collapsing behind an event horizon (which of course does not require much speed at all)?
So many questions…so few answers…
Naive question, but is the concept of gravity as a product of the distortion of space-time considered by its proponents to adequately explain the apparent conundrum of gravity acting instantaneously at a distance?
/Mr Lynn
Carla says: May 5, 2011 at 1:22 pm
goes to show..behind every great man.. is a great woman..
The agreement between Einstein and Maric was made at the time when there was no certainty that Einstein would receive Nobel Prize some 3 years later. Eventually whole amount was supposed to be paid into Swiss account, and ex wife was expected to receive annual income.
However Einstein did not ‘honour’ the agreement, he secretly (as archive correspondence confirms) invested large part of the money in the American stock market and lost everything in the subsequent crash.
Two important points here:
1. Why Mileva Maric would insist on the Nobel Prize money if it was awarded, and not on some more immediate and more certain financial settlement.
2. Albert Einstein did not keep his word.
Perhaps, at least a share of the Prize went to a person who deserved a share, but it was not recognised as such.
Einstein said himself: “The secret to creativity is knowing how to hide your sources.”
Z says:
May 5, 2011 at 2:49 pm
Bothers a bunch of people. Data-mining is even more environmentally unfriendly than gold mining with nukes and aerosolised mercury…
It shouldn’t, because all that means is that they learned to understand their instrument, lending more credence to their result.
does it not count because it isn’t gravity
It doesn’t count. You could have the same effect just standing on the floor. In both cases there is a force balancing gravity.
If it doesn’t count as “anti-grav”, and I’m still subject to local time if I were to use such an apperatus to annul the gravitational field of a black hole
You certainly could [e.g. a rocket motor] to prevent getting close to the hole, but once you are inside the event horizon, no force can saved you.
So does this mean that light emitted past a certain point in the expansion of the distance between us and a star would never reach us because it would need to be faster than light to overcome the expanding?
Yes, but there is an even more fundamental limit. We can not see anything further away than the age of the Universe allows us. Light from a galaxy 1 billion light-years away we’ll never see.
So many questions…so few answers…
We actually have answers to most of this. There is a dearth of good questions.
Leif – I’m not asking about general relativity, and a page of stuff that doesn’t address my specific problem with this is of no use to me.
My post is here: http://wattsupwiththat.com/2011/05/04/einstein-proven-right-again/#comment-653506
If the mass of the Earth is warping space around it which is what is then pulling in stuff which is gravity, it can only be doing this exactly as in the diagram, on a plane. It cannot be extrapolated to three dimensions. Because gravity is happening on every part of our Sphere. The warping then is equally so in all directions from the Earth. These cancel each other out. Therefore, there is no warping.
Since there is zero warping, what are these measuring? A honey surrounding the Earth is not a description of a two dimensional warp field. It’s a something that is being moved about by the spinning Earth in a zero warp field.
Unless you can explain directly and specifically how space is warped in three dimensions in our real three dimensional world, then the concept of there being a warp in space around our Earth into which things are pulled which is gravity is wrong.
While I was posting my previous post, I was thinking that this reminded me of some of the problems I have with AGW explanations and some examples I’ve come across while exploring this. One of which is that NASA had to junk the Stefan-Boltzmann stuff 40 years ago because it wasn’t accurate enough for its moon projects, it related to a flat Earth and they needed to work in three dimensions. Another example is, can’t recall the ‘laws’ offhand, anyway, it’s in measuring the amount of oxygen in the blood by shining a red and a near infrared light through the finger in an oximeter, they each are obsorbed differently and the final measurement has to be adjusted to compensate for the fact that the two ‘laws’ used don’t actually relate to real world conditions.
But, it seems to me. That there is something much more intrinsically wrong with the space warp concept. It is simply unrealistic in a three dimensional world because such a reaction of a body warping space all around it would cancel out the warp, so leaving a zero warp. So that can’t be an explanation for gravity.
DirkH says:
May 4, 2011 at 3:32 pm
So, spacetime behaves a litle bit like honey? Why don’t we just call it ether?
——————————————————;
Good question. I consider it a terrible analogy.
SamG says:
May 4, 2011 at 4:47 pm
I don’t get why the warping of space time is depicted as occurring on a single plane. Is this for illustration purposes only? I would have thought a large body bends space time in every direction.
————————————————-;
It’s difficult to visualize 4d spacetime and a 2d surface. It’s suppose to convey that matter tells spacetime how to bend, and spacetime tells matter how to move.
To Leif Svalgaard:
You may have set yourself up as the in-house physics expert on this blog but the inconvenient truth remains (in spite of your uneducated denial above) that nothing can move in spacetime and time cannot change by definition. Therefore, there is no time dimension as you, Einstein and the rest of the relativist crowd insist and have insisted on for a hundred years. This is rather sad (and almost inexcusable) because many generations of students have been brainwashed into chasing after a red herring. What a waste of intellect. And what a calamity for the world in terms of inhibiting scientific progress and prolonging human misery.
How to Falsify Einstein’s Physics, For Dummies. Read it and weep.
[Second try. It seems that my comments are no longer accepted by Anthony]
To Leif Svalgaard:
You may have set yourself up as the in-house physics expert on this blog but the inconvenient truth remains (in spite of your uneducated denial above) that nothing can move in spacetime and time cannot change by definition. Therefore, there is no time dimension as you, Einstein and the rest of the relativist crowd insist and have insisted on for a hundred years. This is rather sad (and almost inexcusable) because many generations of students have been brainwashed into chasing after a red herring. What a waste of intellect. And what a calamity for the world in terms of inhibiting scientific progress and prolonging human misery.
How to Falsify Einstein’s Physics, For Dummies. Read it and weep.
Anthony,
Why are you no longer accepting my comments? A simple explanation would be the honorable thing to do. You are doing the same thing regarding relativity that the global warming alarmist are doing regarding climate change science. Shame.
Myrrh says:
May 5, 2011 at 3:37 pm
It is simply unrealistic in a three dimensional world because such a reaction of a body warping space all around it would cancel out the warp, so leaving a zero warp. So that can’t be an explanation for gravity.
Your problem is with the 2D analog of space warping. As I’ve said that is a somewhat misleading image. From the page you wouldn’t bother with: “At its core are Einstein’s equations, which describe the relation between the geometry of a four-dimensional, pseudo-Riemannian manifold representing spacetime, and the energy-momentum contained in that spacetime.[32] Phenomena that in classical mechanics are ascribed to the action of the force of gravity (such as free-fall, orbital motion, and spacecraft trajectories), correspond to inertial motion within a curved geometry of spacetime in general relativity; there is no gravitational force deflecting objects from their natural, straight paths. Instead, gravity corresponds to changes in the properties of space and time, which in turn changes the straightest-possible paths that objects will naturally follow.[33] The curvature is, in turn, caused by the energy-momentum of matter.”
Curvature [warp] can be defined in any number of dimensions. I’ll try one more time: http://en.wikipedia.org/wiki/Theoretical_motivation_for_general_relativity gives a backgrounder that you should read and try to understand. You can ask specific questions about specific points of that exposition and I’ll try to explain. It is not good enough that you simply say “I don’t get it”. It takes an effort ‘to get it’. Make that effort.
Juice says:
May 4, 2011 at 4:51 pm
I still don’t see how you can drag space. I can see gravity warping space (can I?) but I don’t get why spinning drags it. It’s as if we have the luminous aether again.
———————————————————————————;
It’s not dragging space – it’s dragging spacetime. Newtonian gravity, i.e., space + time, don’t predict the effect.
Hey Anthony,
Why are my comments being rejected? Why are you censoring me while giving the resident relativist deceiver, Leif Svalgaard, a free rain on your blog? Do you have one standard for climate change and another for relativity?
[Reply: I am doing most of the moderating today, not Anthony, but other duties have been a priority and I haven’t approved comments as quickly I normally do. You are not being censored, your comments have been posted. But you should be cautioned against referring to Dr. Svalgaard, an esteemed solar physicist, in derogatory terms. If you continue, your comments will be deleted. ~dbs, mod.]
Louis Savain says:
May 4, 2011 at 10:18 pm
Do you realize that you are confusing the observed motion of a ticking clock with changing time? Clocks do not measure changing time. They only measure static and abstract temporal intervals.
————————————————————————–;
I think you’re confusing time intervals. The clock in your rest frame should tic at a constant rate (within acceptable precision limits) – otherwise it’s not a clock by definition.
If a second identical clock is moving relative to you at speeds approaching the speed of light, and you use the clock in your rest frame to estimate it’s tick rate, the tick rate of the second clock will change.
Can you guess how it will change? If not, then you need to review the special relativity portion of the book.
Robert Geroch’s book is a great little book on both special and general relativity is highly recommended for anyone curious about relativity.
Leif – again with the free fall in your explanation*, as you’ve given me in a previous discussion and as above, is not what free fall means. So I still don’t understand what you’re saying and it will continue to not make sense to me because it is apparently based on a two dimensional understanding of mass. I can’t follow your explanations on four dimensions because the base is not logical in three dimensions.
Can’t you just answer my three dimensional problem? If there is something called space (or space/time) in which a body impinges warping it, then it must be impinging on it equally with all its mass in every direction, which cancels all the impinging out.
[*You said re free fall: “the Earth is in free fall around the Sun and thus does not feel any gravity [except its own], just like an astronaut in free fall about the Earth.”
This is not the definition/explanation of free fall, which is, that it is only gravity acting on it. So, the Earth feels the Sun’s gravity.
]
Watts up?
Sorry – that free fall info from: http://www.physicsclassroom.com/1dkin/u1l5a.cfm
aggh. http://www.physicsclassroom.com/class/1dkin/u1l5a.cfm
missed the class..
The Physics Classroom – Physics Tutorial – One Dimensional Kinematics Lesson 5
Free Fall and the Acceleration of Gravity
Myrrh says:
May 5, 2011 at 4:32 pm
not make sense to me because it is apparently based on a two dimensional understanding of mass.
That statement does not make sense to me
I can’t follow your explanations on four dimensions because the base is not logical in three dimensions.
Again, does not make sense to me. Spacetime is warped in four dimensions.
Can’t you just answer my three dimensional problem? If there is something called space (or space/time) in which a body impinges warping it, then it must be impinging on it equally with all its mass in every direction, which cancels all the impinging out.
And why would that be? And spacetime does not have three dimensions, so why are you hung up on a ‘three-dimensional problem’?
This is not the definition/explanation of free fall, which is, that it is only gravity acting on it. So, the Earth feels the Sun’s gravity.
gravity acting on it is not the same as feeling gravity. In classical terms we can say that the gravitational force of the Sun is precisely balanced by the centrifugal force of the Earth in its orbit, so that the Earth does not feel any residual force. Same thing with an astronaut in space. If he drops his hammer it will just float there right next to him. They are both weightless and ‘weight’ is just the force with which gravity presses you against the weight-scale. Now, in General Relativity there is no gravity at all, just the distortion of spacetime and a body simply moves in a straight line.
Myrrh says:
May 5, 2011 at 5:01 pm
Free Fall and the Acceleration of Gravity
more on free fall:
“In Newton’s view, astronauts in Earth orbit are in free fall, since they are in effect falling around the Earth [which is free-falling around the Sun]. They are accelerated by gravity toward the Earth, but their inertia in the direction tangential with their path results in a curved path around the planet. In essence, they are always missing the planet in their fall toward it.
One way to view this situation, is to note that gravity by itself does not produce a weight-like force (a g-force) that people can directly sense, since gravity acts upon all parts of the body and the body only senses mechanical stresses (which to a good approximation, gravity does not produce, by itself). Thus, even a person standing on the Earth does not actually feel the pull of “gravity,” but actually feels only the push of the ground, acting upward. If this push of the ground is suddenly removed (for example, in a free fall in an elevator), the person experiences weightlessness, because all the forces which have caused the sensation of “weight” have been removed, even though gravitational interactions continue.
Often, the terms zero gravity or reduced gravity are used to mean weightlessness as it is experienced by orbiting spacecraft. The idea of gravitation itself being greatly reduced in this situation is not technically accurate in the physics of Newton, although it is accurate in the physics of Einstein (general relativity).
Spacecrafts are held in orbit by the gravity of the planet which they are orbiting. In Newtonian physics, the sensation of weightlessness experienced by astronauts is not the result of there being zero gravitational acceleration (as seen from the Earth), but of there being no g-force that an astronaut can feel because of the free-fall condition, and also there being zero difference between the acceleration of the spacecraft and the acceleration of the astronaut.”
Leif – the problem perhaps is that I’m not making myself clear enough?
Your link to the Theoretical motivation for general relativity says:
“General relativity addresses two questions:
1. How does the curvature of spacetime affect the motion of matter?
2. How does the presence of matter affect the curvature of spacetime?”
Doesn’t address my specific point because it begins with an assumption that spacetime curvature exists.
I’m asking specifically about the diagram which may well call itself ‘space/time’ curvature, but is a description of how gravity works in space. It says, that gravity works by a mass impinging on something surrounding it that it can warp, bending it, so an object heading towards that mass will roll into the warped space, (however it does this while travelling in a straight line is irrelevant to me). The space is warped, that’s the claim.
I’m saying that can only be two dimensional, (exactly as in the diagram), because a mass will impinge itself in all directions equally, (if such a thing was happening), cancelling out all the individual impinging on all the points touching the surrounding space, in a three dimensional space.
So, there is no warp.
Louis Savain says:
May 5, 2011 at 3:51 pm
and time cannot change by definition.
So, what is the definition of time? And whose definition?
Stupid question,
in this thread i’ve read nothing can move faster than light (slow as it is),
due to problems with mass.
Yet, the “big bang” theory postulates ??, an expansion much faster than the speed of light. So, is there a speed limit or not?
u.k.(us) says:
May 5, 2011 at 6:00 pm
Yet, the “big bang” theory postulates ??
Actually: measures an expansion much faster than the speed of light. So, is there a speed limit or not?
There is a speed for moving through space[time], but not for the expansion of space. The farthest galaxy we know of sits motionless in space that currently expands at more than 10x the speed of light [we infer this from its measured redshift].
u.k.(us),
An excellent book that answers your question is Prof Brian Greene’s The Fabric of the Cosmos: Space, Time, and the Texture of Reality. Highly recommended.
The expansion of the universe during inflation following the Big Bang was not bound by the speed of light, which is a universal constant – but only within the universe. Greene explains it much better, with very little math involved, except in the appendix. He has a talent for explaining the physics clearly, no matter what the reader’s education level. IMHO, only Asimov was better at explaining things. [Amazon has used copies cheap, and hundreds of good reviews. You can also read a random sample of the book.]
One thing that Prof Greene explains made me do a lot of thinking: he said that by using conservative numbers, physicists determined that if the current size of the visible universe was much smaller than a grain of sand, inflation would have made the total size comparable to the size of the earth.
Our visible universe has a radius of less than 14 billion light years. Even though we cannot have any effect beyond that limit [and vice-versa], that doesn’t mean the universe ends there. That’s just our grain of sand. As every year passes, the radius of our visible universe gets one light year bigger. And the universe is different for each of us, because each of us is in the center of our own 28 billion light year-diameter sphere. There is no ‘edge’ to the universe.
[Snip. Arguing with a moderator’s decision is pointless. ~dbs]
Myrrh says:
May 5, 2011 at 5:17 pm
I’m saying that can only be two dimensional, (exactly as in the diagram), because a mass will impinge itself in all directions equally, (if such a thing was happening), cancelling out all the individual impinging on all the points touching the surrounding space, in a three dimensional space. So, there is no warp.
A massless photon coming towards a massive body from a given direction will deviate from the usual Newtonian straight line and seem to follow a curved [warped] trajectory. This is observed everywhere around the mass and shows that the space is warped everywhere. The warping only depending on the distance from the mass. We see this at every solar eclipse [e.g. at the one in 1919 that made Einstein famous] or when receiving radio signals from spacecraft passing near the Sun. Thus space[time] is observed to be warped. This is an experimental fact. Einstein’s GR theory is the explanation of this [and many other effects that depend on warping]. That you don’t get it, is not a problem of understanding but of fixation with something you can’t even articulate to make sense. You see, in physics, the criteria is not if something makes sense [quantum mechanics does not], but if it has predictive power. GR predicts a frame dragging of a certain size. The experiment that is the topic of this thread has measured just such an effect in accordance with the prediction. This gives us confidence that the equations are a ‘correct’ description of how Nature works to the accuracy we can currently observe.
George E. Smith, no shielding from other masses. I keep thinking people here at least know enough to properly limit such simple examples themselves, my bad.
Leif Svalgaard wrote on May 5, 2011 at 5:20 pm:
Louis Savain says:
May 5, 2011 at 3:51 pm
and time cannot change by definition.
So, what is the definition of time? And whose definition?
I’ll give you an answer but first you must apologize for calling me stupid above. Then, maybe, I’ll apologize for calling you uneducated. Until then, seeing that you have the support of the blog’s current moderator, I’ll refrain from commenting any further.
Here is an explanation of the universe’s size. [Avoid the comments unless you want to go nucking futz.☺]
Louis Savain says:
May 5, 2011 at 8:11 pm
I’ll give you an answer but first you must apologize for calling me stupid above. Then, maybe, I’ll apologize for calling you uneducated. Until then, seeing that you have the support of the blog’s current moderator, I’ll refrain from commenting any further.
Sure, Paris is worth a mass.
Leif Svalgaard says:
May 5, 2011 at 6:20 pm
Smokey says:
May 5, 2011 at 6:41 pm
===============
Thanks for the info guys.
A thought; can we tell which direction the “big bang” started from, by the red shifts of our vision?
Leif,
Thanks for all your great replies and explanations. I learned a lot as usual, and your patience with certain individuals is commendable.
Vuk etc. says:
May 5, 2011 at 5:02 am
Was Einstein the true author of ‘Einstein’ theories?>>>
I won’t give the comment further airing by quoting it. But I will call it drivel. Einstein didn’t nearly flunk math, his school changed their grading system at one point and if you don’t know that it looks like he dropped from top of class to bottom. In fact he was top of class through out. As for attempting to slag him over time frames of publication and his divorce, give me a break. If you are arguing that he produced nothing significant after divorcing his wife, so then the work must have been done by his wife… then one can only wonder why SHE produced nothing of significance after the divorce. If you want to spin the story to new heights of silliness, I suppose you could argue that it was a “man’s world” and so she couldn’t get published without her husband as a proxy. Oddly, if she had anything additional to add that she wouldn’t find another physicist to make famous? Or go have a chat with his great detractor Milliken who designed a ten year long experiment to disprove Einstein, only to prove him right?
I guess in addition to the gene that causes some humans to spew nonsense in order to discredit actual science, there must also be a gene that causes some humans to try and drag greatness into the same mud they reside in.
I find the bending of “space-time” as shown in the picture difficult to visualise,I would need to see something moving before I could tell if it was following a curved path through space.The path that objects take through space near massive bodies is bent I can visualise that,light is also bent by gravity which enables me to visualise the slowing of time.I have always had a problem with this in understanding einstein.
Sorry, I cannot join the collective worship of Dr. Leif Svalgaard (no matter how actively this ritual is encouraged by moderators).
In many cases, Dr. Svalgaard doesn’t give meaningful answers or explanations. Actual intellectual content of his posts, if you look beyond the obfuscating jargon and painful reiterations of the obvious, is difficult to discern.
Dr. Svalgaard repeats textbook definitions and/or gives you a link to a Wikipedia article that contains a textbook definition — or, if you insist on clarification, pretends to misunderstand your question (while totally lacking a normal sense of humor — recall how he repeatedly failed to recognize an obvious sarcasm).
Earlier, I asked a question: “So, the flow of time depends on the presence or absence of a large mass in vicinity. Why this is never taken into account when they talk about red shift?”
Dr. Svalgaard answered: “It is.” And, in support of his learned opinion, he directed me to the Wikipedia article on gravitational red shift effect.
Unfortunately, the article that he recommended as an answer doesn’t contain a single word about how, exactly, the gravitational red shift is being taken into account by the proponents of the Big Bang dogma. This was a regular non-answer from Dr. Svalgaard, just a waste of words and time, spiced up by unwarranted condescension and inflated self-esteem.
Whatever Dr. Svalgaard tells you, take it with a pound of salt. Recent discovery of the super-massive cluster of galaxies on the edge of the IR-visible Universe makes abundantly clear that the Big Bang hypothesis is fundamentally flawed. And yet, Dr. Svalgaard continues to lecture us in the same manner, as if his BBT dogma is as immovable as the space-time itself.
I am sick and tired of Dr. Svalgaard. Without him, this site is like a gulp of fresh air. With him, it is not.
Leif Svalgaard wrote:
Sure, Paris is worth a mass.
Certainly. However, I no longer feel that continuing this discussion is worth it to me. I have no desire to convince you of anything and I need neither your blessing nor your approval. See you around. It’s been fun.
Don’t mean to break in on the Einstein story, but having read this, I thought I would head over to New Scientist and see what they had to say, and instead found this:
Strange Cosmic Ray Hotspots Stalk Southern Skies
They mention:
Now my math isn’t my strong suit, but wouldn’t 0.03 lightyears put that near the Heliosheath ?
Plus, if I could add anything to this story about space time, wouldn’t it be better to view the space time anomaly surrounding Earth as homogeneously spatial, rather than linear?
Todays xkcd seems on topic: http://xkcd.com/
“The four gyroscopes in GP-B are the most perfect spheres ever made by humans. These ping pong-sized balls of fused quartz and silicon are 1.5 inches across and never vary from a perfect sphere by more than 40 atomic layers. If the gyroscopes weren’t so spherical, their spin axes would wobble even without the effects of relativity.”
Except they did wobble, and it took 5 years to pick “a fantastic precision of 0.0005 arcseconds” out of the data.
And here is the claim: “Every future challenge to Einstein’s theories of general relativity will have to seek more precise measurements than the remarkable work GP-B accomplished.”
“Measurements” is not the best term for this process that was undertaken to make 86 new PhDs and confirm Einstein’s GR. The words they need are “massaging” and “modeling.” IEEE Spectrum:
“The project was on very shaky ground, because even after years of data massaging, GP-B had weakly confirmed one of the effects, frame dragging, to only the 25 to 33 percent range. But as Everitt and GP-B spokesman Bob Kahn, of Stanford, told IEEE Spectrum via e-mail, a recent breakthrough in the modeling of behavior of the satellite’s instruments has increased the data’s accuracy ”by a factor of 5 to 10”.”
Zeke the Sneak;
“Measurements” is not the best term for this process that was undertaken to make 86 new PhDs and confirm Einstein’s GR. The words they need are “massaging” and “modeling.” IEEE Spectrum:….>>>>
Let’s not confuse the journey with the destination. If I say that I drove to New York, showing that I spend the first two days of the trip going the wrong way doesn’t mean I didn’t get there. They published their results and my understanding is that they showed how they calculated the wobble in order to isolate the data. If there’s something wrong with how they did it, then attack that and show how it is wrong. Citing an early attempt that was later improved upon means nothing in terms of evaluating the final technique.
Its interesting to see explanations such as “gravity warps the space around a mass”
I always understood it that its the mass that warps the space. Gravity is just the effect that results from that warping – its not the cause of the warping. Any body else ?
Leif says re my “I can’t follow your explanation on four dimensions because the base is not logical in three dimension”:
Again, does not make sense to me. Spacetime is warped in four dimension.
So you say. I have yet to see any proof that it exists, notwithstanding the title claim to proof here. All that this experiment shows is that the Earth’s spin is having some effect on the space around it, which is a ‘thing’; a thing like honey, a thing like ether, a thing like plasma. Whatever. It does not show that there is such a thing as spacetime. That’s still an assumption.
Re my “Can’t you just answer my three dimension problem? If there is something called space (or space/time) in which a body impinges warping it, then it must be impinging on it equally with all its mass in every direction, which cancels all the impinging out”:
And why would that be? And spacetime does not have three dimensions, so why are you hung up on a ‘three-dimensional problem’?
Because it is a three dimensional problem in a three dimensional universe. For a moment, for our discussion, bear in mind that space/time is an assumption, it is simply space in our universe and all that experiment has shown is that space is not empty of stuff. All you are doing is calling this stuff, space/time.
Your claim is that space/time is four dimensions is irrelevant to the three dimensional problem this actually is, and into which relativity itself puts it, it is ‘stuff’ surrounding the Earth in which the Earth impinges in a three dimensional way, by its mass warping it.
So, whether we call it space or ether or space/time or honey or plasma or thin air makes no difference, it is something in which another body moves, like throwing a ball into a lake, it is still a three dimensional problem. Let’s call it stuff. This stuff you say is being warped by Earth’s mass which then creates gravity.
OK. The mass warping stuff around it can only be doing so in one direction to produce the effect of gravity claimed this warping produces. If the mass of Earth is warping the stuff around it, it must be doing it in all directions. Which means that all the directions cancel each other out and there is effectively no warp, because an object approaching it will be ‘passed’ from one warp point to the next.
What we’re looking at in analogy is the mass of the Earth warping the inside of a balloon by its mass, from the inside.
If the mass of the Earth is warping the space around it, the whole of the inside of the balloon, then it is doing so ‘equally’ at every point which cancels out the warps. ‘Equally’ like ‘average’, it could be that the Earth is heavier weighted at some point so its interacting with whatever stuff it’s in is to a greater or lesser amount than ‘equal’.
A massless photon coming towards a massive body from a given direction will deviate from the usual Newtonian straight line and seem to follow a curved [warped] trajectory. This is observed everywhere around the the mass and shows that the space is warped everywhere. The warping only depending on the distance from the mass.
But as before, you’re still presenting a three dimensional scenario. The mass of the Earth impinging on the stuff around it equally in all directions which has an effect on something coming from any particular direction. This doesn’t ‘disprove’ Newton and straight lines in any way. Something will travel in a straight line unless it’s acted on by another something. The effect on it greater the closer it gets to something which can have an effect on its path shows only that the space between the objects is a something a heavier mass affects more than something lighter.
We see this at every solar eclipse [e.g. at the one in 1919 that made Einstein famous] or when receiving radio signals from spacecraft passing near the Sun. Thus space[time] is observed to be warped. This is an experimental fact. Einstein’s GR theory is the explanation of this [and many other effects that depend on warping].
“Thus space[time] is observed to be warped” – Thus space is observed to be warped, not spacetime, so thank you for the brackets. But as above, it’s still a 3D problem, of surfaces meeting. And all it shows is that the space around the Earth is a something which is affected by Earth’s mass.
that you don’t get it, is not a problem of understanding but of fixation with something you can’t even articulate to make sense.
The fixation, as I see it, is that you have called simple 3D reality 4 by including time and then use only 3D reality to explain it. And then complain I don’t understand.. A 3D reality which stands on its own as I’ve gone through above raises questions enough.
So, what I’m trying to understand is how this mass of Earth impinges on the surrounding stuff. If it is impinging really equally in all directions actually distorting the stuff around it equally in all directions, then any effect it would have at any discrete point is cancelled out. Like a ball just heavy enough to be suspended in the middle of a bath full of water.
Like air pressure perhaps? The weight of the gas Air on the Earth is around a ton/square foot, but it’s said that it is pressing on us equally in all directions so we don’t feel it.
But, like Air pressure, it could be that the stuff around the Earth is exerting pressure equally all around on the Earth as much as it could be that the Earth is impinging equally on the stuff all around.
Anyway, as for something falling to Earth in free fall, it’s still a straight line. The astronaut falling to Earth doesn’t get sucked into a ‘vortex’, if such exists by the warping, at any point because his mass is heavy enough to counter any such, a smaller photon might get caught up in such, but we know that light from the Sun comes to us in a straight line, don’t we? And it doesn’t go into an orbit around the Sun after escaping from it as radiation.
You see, in physics, the criteria is not if something makes sense [quantum mechanics does not], but if it has predictive power.
? I thought the point of science was to understand our natural world, how it worked. You may well be able to predict something but attributing it to the gods, but that isn’t an answer of how it works.
GR predicts a frame dragging of a certain size. The experiment that is the topic of this thread has measured just such an effect in accordance with the prediction. This gives us confidence that the equations are a ‘correct’ description of how Nature works to the accuracy we can currently observe.
Does it? All it shows it seems to me is whatever you have taken as ‘time’ in the ‘space/time’ you call warping, which is really only a 3D model of an object with mass in stuff, is irrelevant to the effect of warping. Except in that the speed of a lighter object is less affected by the mass of a heavier body the further away it is from it.
Doesn’t prove time speeds up, but only that an object can go faster the further it is from a force which can slow it down. I read the page on time linked above. And I couldn’t find anything in it that showed time is affected, only speed.
Leif – re my: “Which means that all the directions cancel each other out and there is effectively no warp, because an object approaching it will be ‘passed’ from one warp to the next.”
Sorry, thinking of something else while typing another. If all the points are equally impinging so there’s no actual ‘vortex of gravity’ at any point, then it’s the spin of the Earth which is disturbing the stuff around it, and so something’s path could be distorted in approaching Earth, in effect like being passed from one point to the next. How it gets through this is still normal 3rd physics, depending on it own weight and speed. So radio signals can be bent around, to resume after in the same line or become so distorted in the process that they disintegrate into shash.
Isn’t this how light was discovered to be a wave as well as a photon? That it could bend round corners.
Leif Svalgaard says:
May 5, 2011 at 8:12 am
tallbloke says:
May 5, 2011 at 8:04 am
I guess in order to ‘rescue the data’ the scientists must have found some systematic ‘aberrations’ in the gyroscope headings. Have they documented those and found satisfactory explanations for them?
In order to interpret the data you must first understand your instrument. Such understanding often comes after the experiment when unexpected effects show up. But, yes, they have documented this and, more importantly, understand why they occurred.
Terrific. Where is this documented so we can have a look?
In many cases, Dr. Svalgaard doesn’t give meaningful answers or explanations. Factual content of his posts, if you look beyond the obfuscating jargon and painful reiterations of the obvious, is difficult to discern.
Dr. Svalgaard repeats textbook definitions and/or gives you a link to a Wikipedia article that contains a textbook definition — or, if you insist on clarification, pretends to misunderstand your question (while totally lacking a normal sense of humor — recall how he repeatedly failed to recognize an obvious sarcasm).
Earlier, I asked a question: “So, the flow of time depends on the presence or absence of a large mass in vicinity. Why this is never taken into account when they talk about red shift?”
Dr. Svalgaard answered: “It is.” And, in support of his learned opinion, he directed me to the Wikipedia article on gravitational red shift effect.
Unfortunately, the article that he recommended as an answer doesn’t contain a single word about how, exactly, the gravitational red shift is being taken into account by the proponents of the Big Bang dogma. This was a regular non-answer from Dr. Svalgaard, just a waste of words and time, spiced up by unwarranted condescension and inflated self-esteem.
Whatever Dr. Svalgaard tells you, take it with a pound of salt. Recent discovery of the super-massive cluster of galaxies on the edge of the IR-visible Universe makes abundantly clear that the Big Bang hypothesis is fundamentally flawed. And yet, Dr. Svalgaard continues to lecture us in the same manner, as if his BBT dogma is as immovable as the space-time itself.
The issue of time vs change is discussed here for all you time deniers :p.
http://telicthoughts.com/philosophy-and-metaphysics-interlude-creation-ex-nihilo-vs-change-2/
Anthony,
Science still has not included the forward momentum of the solar system to be of any consequence. So, motion is not included.
Changing of circular motion speeds also changes the gravity being felt as now centrifugal force has increased or decreased.
Global rotation is far more complex than a circle on a single plane in motion.
Jupiter mass is more than 300 times the Earth’s, the surface gravity is ~2.5G. Jupiter’s orbit is the place where theory will be conclusively verified or dismissed.
Joe Lalonde says:
May 6, 2011 at 5:12 am
Anthony,
Science still has not included the forward momentum of the solar system to be of any consequence. So, motion is not included.
Changing of circular motion speeds also changes the gravity being felt as now centrifugal force has increased or decreased.
Global rotation is far more complex than a circle on a single plane in motion.
~
good comment.
Alexander Feht says:
May 6, 2011 at 4:53 am
~
Some of us here need a little textbook knowledge and subsequent explainations as given by Dr. S.
And for the record I personally have never been on my knees before him.. lol did I say that..whooaa..Happy Friday..
Myrrh,
You have articulated a question that I have often thought about. For what it’s worth, here’s my take on the warping of spacetime.
As I understand it, I think you are correct – 3d space is not warped – that wouldn’t make sense. The presence of matter makes time run slower and therefore what is being warped is time. You have to think of 4d space-time that is being warped, and the warping is because of the time dimension, not the 3 spatial dimensions. A particle curves towards the Earth because time is running more slowly closer to the Earth. It is a rule of GR that a particle will move from one place to another so that a clock carried on it will show a longer time than it would on any other trajectory. This is a reason why the particle moves towards the Earth. If it didn’t do so, its clock would show a shorter time. From the framework of 4d spacetime, we say that the particle is following the shortest distance in spacetime – ie, a straight line through spacetime – and in doing so the particle moves in a curve through space, but the space itself isn’t warped.
On spacetime: http://www.ws5.com/spacetime/ which has many good links. Especially this one: http://www.perimeterinstitute.ca/Outreach/Explore_Our_Universe/What_is_Warped_Spacetime?/
Some people apparently just can’t accept reality. Einstein’s special & general relativity make extremely precise predictions — if results are even slightly off, his theories would be toast. So far, every prediction has been verified.
No one says relativity is complete — it’s not meant to address the very tiny scales. That’s different from being wrong, just incomplete.
Again: this needs unpacking. If you’re wondering why you’re being ill-treated, it just might be the glib arguments-by-assertion.
If you seek to illuminate, by all means have at it. What you’ve been doing looks more like trolling, from where I stand.
FWIW.
Myrrh says:
May 5, 2011 at 1:07 pm
“Is no one giving me an explanation to my question because no one knows the answer?”
I don’t think the picture is meant to be taken literally. It is drawn that way because if you draw every possible angle in 3d you would just see a sphere of ink. It is drawn in the two dimensions so you can see the shape and once understanding the concept use your mind to apply it to the 3rd dimension.
“”””” Leif Svalgaard says:
May 5, 2011 at 1:44 pm
Myrrh says:
May 5, 2011 at 1:07 pm
Is no one giving me an explanation to my question because no one knows the answer?
The answer is long. Wikipedia has some good pointers: http://en.wikipedia.org/wiki/General_Relativity
Because this is a very simple problem, it surely can’t be beyond your abilities to explain it.
It may be beyond your ability to understand it. By that I mean, that there are fundamental issues about what curvature is and how to express it, and those are not easy to visualize, without resorting to somewhat misleading images [like the bowling ball on a membrane]. Start with the wiki. There are also good books on the subject [referenced in the wiki]
George E. Smith says:
May 5, 2011 at 1:18 pm
I always thought gravity had an infinite range so that shielding is inherently impossible.
The Earth is in free fall around the Sun and thus does not feel any gravity [except its own], just like an astronaut in free fall about the Earth. “””””
So if the earth (at its center) does NOT feel any gravity; then why doesn’t it just stop falling; why does it not “……continue in a straight line, unless acted on by an external force…..” As that Isaac Newton chap suggested should happen ?
>>
George E. Smith says:
May 6, 2011 at 11:11 am
George E. Smith says:
May 5, 2011 at 1:18 pm
I always thought gravity had an infinite range so that shielding is inherently impossible.
The Earth is in free fall around the Sun and thus does not feel any gravity [except its own], just like an astronaut in free fall about the Earth. “””””
<<
It’s sloppy terminology. I’m giving up correcting statements on this thread, because my corrections have more errors that the original posts. However, even astronauts in free fall feel gravity about the Earth. They have weight which is defined as the acceleration of gravity (at their height). The forces may cancel, but the gravity is still there. This is especially true if you’re in free fall around a medium-sized black hole near the event horizon (or closer). You’ll be dealing with the “gravitational” tidal force which will probably tear you apart even though you may feel “weightless.”
Jim
davidmhoffer says:
May 6, 2011 at 1:50 am
Zeke the Sneak;
“Measurements” is not the best term for this process that was undertaken to make 86 new PhDs and confirm Einstein’s GR. The words they need are “massaging” and “modeling.” IEEE Spectrum:….>>>>
Let’s not confuse the journey with the destination. If I say that I drove to New York, showing that I spend the first two days of the trip going the wrong way doesn’t mean I didn’t get there. They published their results and my understanding is that they showed how they calculated the wobble in order to isolate the data. If there’s something wrong with how they did it, then attack that and show how it is wrong. Citing an early attempt that was later improved upon means nothing in terms of evaluating the final technique.
I am showing how the methodology behind this finding yields nothing near as precise as is being claimed. There is a lot of micetype on the exquisiteness of GP-B’s results and I think people should have a look before getting mesmerised by the press releases and signing for it. 5 years of computer processing on a wobbling gyroscope plus a computer model correction at the last minute when funds ran out for Stanford is a considerable caveat. What does this experiment really tell us?
George E. Smith says:
May 6, 2011 at 11:11 am
then why doesn’t it just stop falling; why does it not “……continue in a straight line, unless acted on by an external force…..” As that Isaac Newton chap suggested should happen ?
That chap Einstein suggests that the Earth follows a straight line [geodesic] in curved spacetime.
Jim Masterson says:
May 6, 2011 at 12:14 pm
However, even astronauts in free fall feel gravity about the Earth. They have weight
I think they would say that they are weighless. You cannot ‘feel’ gravity, only differences in gravity which put stress on your body.
Leif Svalgaard says:
May 5, 2011 at 3:02 pm
It shouldn’t, because all that means is that they learned to understand their instrument, lending more credence to their result.
Understanding is always tempered by wish-fulfilment, that’s why I’m a great believer in everything being simple and plain. OK, I admit getting something round to an atom is far from simple – but the concept of “round” is easy to understand.
The concept of “do a lot of complicated procedures on a pile of crap data until it sings like a canary” is easy to understand too – just in a different way.
I think this ( http://www.creditwritedowns.com/2011/05/confirmation-bias-as-a-feature-not-a-bug-the-facts-dont-really-matter.html ) is quite a good piece – though it may be in a Galaxy Far Far Away from cosmology.
It doesn’t count. You could have the same effect just standing on the floor. In both cases there is a force balancing gravity.
You don’t have the same effect standing on the floor. Go back to the Einstein “man in an elevator” thought experiment. A man in an elevator doesn’t know whether he’s accelerating, or he’s under the influence of gravity. Similarly, he doesn’t know whether he’s falling, or under the influence of magnetism…
You certainly could [e.g. a rocket motor] to prevent getting close to the hole, but once you are inside the event horizon, no force can saved you.
Why? I though the event horizon stopped things getting out, not in. The idea is not to keep away from the hole, but to prevent tidal forces from shredding you. Drop through the event horizon intact, and all sorts of censorship problems disappear.
Yes, but there is an even more fundamental limit. We can not see anything further away than the age of the Universe allows us. Light from a galaxy 1 billion light-years away we’ll never see.
I think you missed my point. Universe is (estimated and rounded – start waving your hands here) 14 billion years old. Therefore we can’t see anything further than 14 billion LY away. Simply because there isn’t light old enough to gone any further. If some part of the universe has expanded at 10 times lightspeed starting at T-2billion years (say) and lasted for 1 billion years (for example), then we won’t be able to see anything of the universe that emitted light between those two time frames. We’ll see older stuff which traversed the “expansion zone” before it expanded, and younger stuff which is before the “expansion zone”, but anything that emitted during the “expansion” will still be travelling. A 10 billion LY gap will take 10 billion LYs to traverse, and it didn’t happen far enough in the past for that.
I would have thought that would have been noticed.
Obviously the whole universe didn’t expand at 10 times light speed but only select areas, as I’m sure many of the older stars would have noticed their bits becoming distant otherwise.
Leif Svalgaard says:
May 5, 2011 at 7:24 pm
A massless photon coming towards a massive body from a given direction will deviate from the usual Newtonian straight line and seem to follow a curved [warped] trajectory.
Well I would point out that a travelling photon isn’t massless – E=Mc^2 and all that. A stationary photon is massless, but since they don’t actually exist, it’s easy to see how you can achieve that little trick.
Though one of the other posters has come up with something that leads to a bit of a poser. If the net attraction of a perfect ball within a perfect sphere is zero – does that still apply if you spin it?
“”””” Leif Svalgaard says:
May 6, 2011 at 1:15 pm
George E. Smith says:
May 6, 2011 at 11:11 am
then why doesn’t it just stop falling; why does it not “……continue in a straight line, unless acted on by an external force…..” As that Isaac Newton chap suggested should happen ?
That chap Einstein suggests that the Earth follows a straight line [geodesic] in curved spacetime.
So all of the planets, and I presume, everything else in THE Universe are travelling in a straight line. I suppose it is the same straight line for all of them. So why do some of them collide into each other now and then ?
Are we all going somewhere or does this straight line, always end up in the same place. Why doesn’t everything just stay in the same place all the time; why move ? What does move mean anyway ?
G. Karst:
At May 5, 2011 at 10:12 am you ask me:
“No particle is born void of velocity. Why do we assume, the universe came out of the big bang, without velocity?? GK”
I answer that no assumption is needed.
1.
A velocity is a rate of movement as observed from a stationary point.
2.
The universe is everything so it cannot be observed to move because there is no external reference point from which to make the observation.
I hope the point is now clear.
Richard
Slartibartfast says:
May 6, 2011 at 9:35 am
Time cannot change by definition.
Again: this needs unpacking. If you’re wondering why you’re being ill-treated, it just might be the glib arguments-by-assertion.
If you seek to illuminate, by all means have at it. What you’ve been doing looks more like trolling, from where I stand.
I explained it already. See comment above on May 4, 2011 at 7:52 pm. It’s a very simple thing really. And it is known to many people, including some relativists. Don’t believe Leif Svalgaard when he says that the earth follows a straight path (geodesic) in curved spacetime. And it does not matter if Einstein said it. It’s all BS because nothing can move in spacetime. That’s right; no time travel, no black holes, wormholes and all that other Star-Trek voodoo physics nonsense.
It’s a devastating truth about general relativity and it’s the reason that you will not hear it from professional deceivers like Stephen Hawking, Brian Greene and the others. They’ve been lying from day one. However, many relativists like Leif Svalgaard here, are just ignorant of this truth. It never fails to catch them by surprise.
Louis Savain:
You have repeatedly demanded answers from Leif Svalgaard.
But you have not answered my polite question to you at May 5, 2011 at 7:02 am.
Please note that my question was a request for you to tell me the errors you think exist in my understandings of relativistic theory which I itemised. This seems a small request when compared to the detailed demands you have made of Leif Svalgaard so I wonder why you have not responded to it.
Richard
Louis Savain:
Please answer my polite request to you at May 5, 2011 at 7:02 am.
It seems a small thing to ask when compared to the detailed demands you have since made to Leif Svalgaard.
Richard
Louis Savain,
There is a good reason for education credentials. If someone has a PhD in Mathematics, we can pretty much rely on what he says, even if we can’t understand all of it.
Dr Hawking, Dr Greene and Dr Svalgaard all have legitimate credentials in their respective fields, so you cannot seriously call them ‘ignorant.’ And just because they may not agree with you does not make them ‘professional deceivers’ or ‘liars.’ I think you need to back off the pejoratives, and accept the possibility that you could simply be wrong.
BTW, what is the extent of your education, and in what field? That will assist in deciding if you should be taken as seriously as those you are attacking.
davidmhoffer says: May 5, 2011 at 10:01 pm
…………..
Thank you for your analysis.
ETH Zurich has exam records.
Facts on record are :
Mileva Maric insisted on ‘any future Nobel Prize money’.
Einstein agreed.
Maric kept her mouth shut for the rest of her life.
Einstein did not keep fully to the agreement.
Einstein: “The secret to creativity is knowing how to hide your sources.”
Smokey,
You are repeating the old “credentials” false argument. It is a favorite of the establishment crackpots because this is how they fool the public into believing that they alone (the crackpots) can understand science and nature and explain it to the rest of us. Just like the high priests and wizards of old. But we are not fooled any longer. We, too, can think for ourselves. Surprise!
The truth is that reasoning has nothing to do with credentials. It has to do with simple logic that everybody can understand. If you cannot understand the simple reasons that I gave earlier to defend my contention that time cannot change and that, as a result, nothing can move in spacetime, then something is either wrong with you or you are one of the deceivers.
I always tell it like I see it.
Juice says:
May 4, 2011 at 4:51 pm
“I still don’t see how you can drag space. I can see gravity warping space (can I?) but I don’t get why spinning drags it. It’s as if we have the luminous aether again.”
Saying space is being “dragged” is an unfortunate metaphor. What is happening is that the geodesic lines are slightly skewed, such that a body with no external force acting on it follows a path which deviates slightly from that which it would follow about a non-spinning object.
Louis Savain says:
May 4, 2011 at 7:52 pm
“A change in time also implies a rate of change which is given as dt/dt, which is, of course, nonsense.
Figure it out on your own.”
The same could be said of a Galilean universe. A path on a circle embedded in two dimensions obeys x*dx + y*dy = 0. Thus, x*dx/dx + y*dy/dx = 0. But, dx/dx = 1. Does that mean one cannot move around the circle, because x is stationary?
ferd berple says:
May 4, 2011 at 9:10 pm
“From the point of view of the folks onboard the spaceship, they have travelled much faster than light.”
How, when it took 13 billion years for the light to reach there? It’s not like they carried the light they see on the spacecraft with them, and got it there in 60 years.
Myrrh says:
May 5, 2011 at 1:01 am
“As with a couple of others here, I still don’t understand what this warping of space time actually is, how does the Earth warp the space time around it as per the diagram since it must be doing so in all directions, unless this is all based on an idea of a flat universe?”
Forget about the diagram. It is only an analogy which is failing to provide you with the correct insight.
Jim Masterson says:
May 5, 2011 at 1:23 am
“It’s harder to show mathematically, but a ring can’t orbit around a star either (as in Ringworld).”
But, it can remain steadily oriented in space through gyroscopic stiffness, and its CG will move approximately with the Star’s CG. Some stationkeeping may be needed to deal with stray forces which act differently on the Star and the ring.
Geoffrey Donald Broadbent says:
May 5, 2011 at 4:12 am
“I just cannot grasp how he imagined the concepts he did let alone convert them to exacting mathematics.”
He stood on the shoulders of giants like Riemann and others. Hilbert actually derived GR first, but graciously allowed Einstein to claim full credit since he got the ball rolling, as it were.
Dan says:
May 5, 2011 at 7:03 am
“If time, as Einstein suggests, does not exist but is only a succession of events, the succession of events like passenger metabolism, nuclear decay etc, will happen at the same rate aboard the space ship as on the earth.”
There is no requirement that it do so. In physics, it is said that whatever is not specifically prohibited is mandatory.
G. Karst says:
May 5, 2011 at 7:48 am
Is it possible to expand space without expanding time??”
Yes.
G. Karst says:
May 5, 2011 at 10:12 am
“Why do we assume, the universe came out of the big bang, without velocity??”
Even in Newtonian mechanics, all inertial frames at constant velocity are equivalent, in that the same physical laws hold in each.
mkelly says:
May 5, 2011 at 10:45 am
Last night on “How the Universe Works” it was said that the laws of physics allow the creation of energy from nothing.”
Yes, you just have to create equal parts pro-nothing and anti-nothing. Why we do not see equal amounts of anti-nothing is a matter of active investigation.
Stephen Rasey says:
May 5, 2011 at 11:21 am
“The Frame Drag is irrelevant in a typical Fiber Optic Gyro, but it matters when the FOG surrounds a rotating planetary mass.”
Yes, but the effect is relatively small. That is why they needed such a precision instrument to see this effect in the first place.
Leif Svalgaard says:
May 5, 2011 at 8:34 am
“Some of the farthest galaxies found have a red shift in excess of 10… which if the galaxy was moving through space would amount to 10 times light-speed.”
That is incorrect. If it were moving faster than the speed of light, we would never see it. This is known as the Horizon Problem.
Myrrh says:
May 5, 2011 at 3:37 pm
“If the mass of the Earth is warping space around it which is what is then pulling in stuff which is gravity, it can only be doing this exactly as in the diagram, on a plane. It cannot be extrapolated to three dimensions.”
Why not?
Myrrh says:
May 5, 2011 at 5:17 pm
“I’m saying that can only be two dimensional, (exactly as in the diagram), because a mass will impinge itself in all directions equally, (if such a thing was happening), cancelling out all the individual impinging on all the points touching the surrounding space, in a three dimensional space.”
You need to integrate the pull over the entire mass. Gravity surrounding a spherical mass behaves externally just as though the mass were concentrated at a single point in the center.
Alexander Feht says:
May 6, 2011 at 4:53 am
“Unfortunately, the article that he recommended as an answer doesn’t contain a single word about how, exactly, the gravitational red shift is being taken into account by the proponents of the Big Bang dogma.”
It is taken into account, but it is much, much smaller than the Doppler shift.
Joe Lalonde says:
May 6, 2011 at 5:12 am
“Changing of circular motion speeds also changes the gravity being felt as now centrifugal force has increased or decreased.”
Changing the speed requires an external force, which alters the orbit predictably.
Vince Causey says:
May 6, 2011 at 5:46 am
“The presence of matter makes time run slower and therefore what is being warped is time.”
Actually, both space and time are warped. Visualizing that is one of the things which makes the subject so challenging.
I think that a clock( including atomic ones) , which is a mechancal device is different from “Time”, i.e time does not change when mechanical devices does. Therefore I think that nothing is “proven” regarding relativistic time by this study. Mechanical devices, not time, are disturbed by speed and gravity.
Harry says:
May 6, 2011 at 3:30 pm
“Mechanical devices, not time, are disturbed by speed and gravity.”
What’s the difference? Time is the rate at which atomic processes – which encompasses mechanical, chemical, and any other process – occur with respect to one another.
Moderator – did my longer list of replies to others get eaten by the spam filter?
Oh, there it is. Never mind…
Should have said cosmological red shift.
responding to Leif Svalgaard @ May 5, 2011 at 8:34 am:
I should have pointed out that relative velocity of 98.36% of the speed of light would give a Doppler redshift of 10.
Bart wrote:
Louis Savain says:
May 4, 2011 at 7:52 pm
“A change in time also implies a rate of change which is given as dt/dt, which is, of course, nonsense.
Figure it out on your own.”
The same could be said of a Galilean universe. A path on a circle embedded in two dimensions obeys x*dx + y*dy = 0. Thus, x*dx/dx + y*dy/dx = 0. But, dx/dx = 1. Does that mean one cannot move around the circle, because x is stationary?
Huh? Are you serious or are you just grasping at straws? You realize that dx is not an evolution (change) parameter in physics, don’t you. The only acceptable evolution parameter in physics is dt, a temporal interval.
Me thinks you are one of the deceivers. Thanks for the laughs.
Two days and still running like mad…
Louis Savain is rather dogmatic about dismissing the “dogmatic” views of the establishment… it’s quite interesting really… but it’s very sad to see such religious self righteousness from someone pretending to have the “truth”… oh well…
And in true religious intonations and fervour, “As for me and my house… I name Louis Savain a pushy unimaginative pompous and under educated fraud…”
What say you? … I say “ban the fraud” … but then again I guess all blogs need trolls…
Louis Savain says:
May 6, 2011 at 5:12 pm
Change x to t, then, if you must see things that way.
Really, you are making no sense at all. I think we, you and I, are done.
David Hilbert on the derivations of the field equations: “Every boy in the streets of Gottingen understands more about four dimensional geometry than Einstein, yet, in spite of that, Einstein did the work and not the mathematicians.”
===============
Andrew says:
May 6, 2011 at 5:48 pm
<ad hominem deleted
You may have an intelligent argument hidden somewhere but I’m not holding my breath waiting for it.
Bart says:
May 6, 2011 at 5:49 pm
I think we, you and I, are done.
Bye.
wayne says:
May 4, 2011 at 4:23 pm
“Neat picture but somewhat misleading if you take it too literally! Don’t look at that green-blue mesh and think that is what the real signature of Earth’s gravitational field would actually look like, well, kind of, but not correct.
At the center of the Earth there is no gravity field, zero.”
It’s only the net acceleration due to gravity that is cancelled out. You are confusing that with the field density, which should be at a maximum at the centre of the Earth. (i.e. There should be no need to show an inverted dimple in the grid as proposed earlier.)
George E. Smith says:
May 5, 2011 at 1:18 pm
“Somebody should quickly inform the sun, that it is having no effect at the centre of the earth, probably because of all the magnetic shielding around that point. Oh I forgot, that all that iron would be above the curie Temperature.”
Ah, I love sarcasm, but it seems to have got the better of you. The gridmap takes no account of the effect of the sun’s gravity. 😉
And the Curie temp affects magnetic properties (permeability, susceptibility, etc.) as I’m sure you are well aware, so if you’ve solved the problems of electromagnetogravitation then, please, don’t hold back.
“I always thought gravity had an infinite range …”
Yes. Looking carefully at the diagram I notice a “heliopause” in the drag frame, yet I doubt there should be any reason to expect any such dragpause, or spinpause.
Smokey, lacking a PhD is a problem for some of us.
Perhaps one could dress in a cape and give the ol “ant on the surface of a balloon= expanding universe” lecture?
http://wattsupwiththat.com/2011/05/04/einstein-proven-right-again/#comment-654069
Slacko says:
May 6, 2011 at 7:41 pm
wayne says:
May 4, 2011 at 4:23 pm
“Neat picture but somewhat misleading if you take it too literally! Don’t look at that green-blue mesh and think that is what the real signature of Earth’s gravitational field would actually look like, well, kind of, but not correct.
At the center of the Earth there is no gravity field, zero.”
It’s only the net acceleration due to gravity that is cancelled out. You are confusing that with the field density, which should be at a maximum at the centre of the Earth. (i.e. There should be no need to show an inverted dimple in the grid as proposed earlier.)
No, I wasn’t speaking of field density but acceleration. You think it would be at maximum but I know there is none at the center, in fact, no such field exists at all. It is just that if you could hollow out a room at the center of the Earth to perform an experiment you would find no acceleration from gravity at all, no curvature of geodesics, flat space and you would be weightless. Gravity in Einstein’s general relativity is not a field, I did mention that didn’t I, well, I shouldn’t have, my mistake, that is a conceptional effect of the curvature itself.
The dimple needs to be there for the lines shown seem to be representing the acceleration caused by the curvature and there isn’t any at the center and it does decrease linearly (if the density is constant) all of the way from the surface downward to the center. The general idea of that graphic is fine but for that tiny detail.
If you don’t believe it write a small program to integrate it numerically, maybe you have not been surprised by that very fact yet. Before I did that very thing a few years ago I didn’t realize that. Now I do so though others might learn a bit from my effort.
Bart said on Einstein proven right, again
May 6, 2011 at 5:05 pm
I should have pointed out that relative velocity of 98.36% of the speed of light would give a Doppler redshift of 10.
Doppler or cosmological red shift, it makes no difference. At a red shift of 10 the expansion speed is the equivalent of 10 x light speed, but since the galaxy is not moving at all we can easily see it. What happens is just that the wave length of the radiation is getting larger and larger, 10x in fact.
I think that I beginning to understand this a bit better,the equations of Newton and Einstein don’t deal with actual space and time just our measurement of space and time,Einstein though sees Gravity as a field rather than as an attraction between two objects.
Moderators, please do not let people who do not even know mathematics crowd the place with nonsense. This gentleman Louis Savain does not know simple differential equations, when he claims that dt/dt is constant means that time does not change.
He cannot understand the simple concept that variables are checked against each other and produce functional shapes in either space or time, not against themselves.
Has he not been given enough exposure? He has his own site anyway.
Bart, May 6:
I am pleased to be included in your discussion.
However, you are missing my point, and that is probably my fault, that the succession of events outside and inside of our bodies ARE what we percieve as time flowing. Just like the cogs on the gears in a clock, where one particular cog must meet another particular cog for the next pair to be able to meet, we have the sensation of time as events pass in succession in our field of view.
These successions will probably be at the same rate everywhere, happening at a discrete fraction of c, which appears to be a universal figure.
The Lorentz transformations make objects appear not to travel faster than light, but in their own frame they do. How would the rocket know when to stop accellerating and instead gain mass? And in reference to what?
I found that this view of time helped a lot when reading Einsteins book. You may say it led to my misunderstanding of the subject, but I am not so sure of that.
Leif Svalgaard says:
May 6, 2011 at 10:07 pm
“Doppler or cosmological red shift, it makes no difference.”
It makes a huge difference.
“At a red shift of 10 the expansion speed is the equivalent of 10 x light speed.”
The relationship you are using only holds in the low redshift regime.
Headbomb and Blackburne
Wot de Hell is going on?
Wicked Pediants.
=========
Bart says:
May 7, 2011 at 2:27 am
“Doppler or cosmological red shift, it makes no difference.”
It makes a huge difference.
“At a red shift of 10 the expansion speed is the equivalent of 10 x light speed.”
The relationship you are using only holds in the low redshift regime.
My point is that the expansion speed can exceed light speed as your graph shows.
I suspect that everything in G.R. could be explained by viewing space as a collection of processors (one per Planck unit of space) and matter as information.
For example, the more matter in the vicinity of any space unit would require more “processing time”. Hence, external to that unit, “time” would slow down. It would be interesting if someone (smarter than me) would try and determine a processing algorithm that would encompass what we see in physics. Or, maybe someone or team is already working on it.
It wouldn’t mean the analogy is correct, but it might lead to further insights.
Louis Savain;
The truth is that reasoning has nothing to do with credentials. It has to do with simple logic that everybody can understand. >>>>
Unfortunately sir, some reasoning is rather complex and cannot be reduced to simple logic that everybody can understand. Credentials or no credentials, some problems require genius to understand and solve. It may not require genius to understand their work, but it may require high intelligence and considerable education. What was a difficult (but solvable) problem for Einstein is a work of wonder for some who study for years to understand it and add to it through experimentation or other means, a matter of interest for some who understand it in general and can see the real world results of application of the better understood portions, and some people lack either the education (formal or otherwise) and/or intelligence to understand at all.
Einstein supposedly said everything should be made as simple as possible, but not simpler. Your arguments through out this thread are a classic example of over simplifying by an order of magnitude.
By analogy, almost anyone can be taught how to drive a car. Quite a few people can taught how to fix one. Some people, with the assistance of computers, can design working components for a car. Very very few people actually understand in detail exactly how the explosion of the fuel/air mixture in the combustion chamber works to the point that they can improve upon it.
By your thought process, cars don’t work because you demand a simple explanation for what happens in the combustion chamber, and there just isn’t one. Unfortunately, millions of people who also don’t understand, and couldn’t if they wanted to, get into their cars every day and drive around.
Leif Svalgaard says:
May 7, 2011 at 5:26 am
“My point is that the expansion speed can exceed light speed as your graph shows.”
Yes, according to current theory, it can. But, that is old news to me. What I am perplexed by is that, I was taught that nothing could be observed beyond the Hubble radius. That’s no problem, as this object falls within the Hubble radius (13.2 Mly versus 13.8 Mly). But, with a Hubble constant of ~71 km/sec/Mpc, that translates to a recession velocity of 0.96 times the speed of light. Yet, the Wikipedia chart I linked to says it should be about 1.3 to 2.3 times the speed of light if the redshift is 10.3.
I’m not sure how this redshift number is being calculated or what it means. Have to go back and brush up on the subject…
davidmhoffer says:
May 7, 2011 at 9:33 am
blah, blah, blah
Time cannot change by definition and nothing can move in spacetime for a very simple logical reason that even school kids can understand. If you don’t get it, don’t blame me. Blame yourself. You are either mentally challenged or you are one of the deceivers. See you around.
anna v says:
May 7, 2011 at 1:34 am
Moderators, please do not let people who do not even know mathematics crowd the place with nonsense. This gentleman Louis Savain does not know simple differential equations, when he claims that dt/dt is constant means that time does not change.
Don’t blame me for your own stupidity. And trying to shut me up is not going to work. I’m planting seeds all over the place and there is nothing you can do about it.
REPLY: Actually yes there is, your behavior is getting out of bounds – so since you said in the previous comment “see you around”, I plan to enforce that stated position of yours, even if you write another whiny blog post about it like you did last time you were snipped by a moderator. – Anthony
Dan says:
May 7, 2011 at 2:05 am
“These successions will probably be at the same rate everywhere…”
This is very tricky topic. It plays all sorts of havoc with our intuition. Indeed, the first place to start is in defining time. What is time? We tend to think of time as fundamental, as some underlying absolute bedrock of reality. But, it is actually nothing of the sort. It is completely relative. How many clock ticks take place before we perceive we have digested a big meal, for instance? The time we take to digest the meal is relative to the time it takes for the clock to tick N times.
The number of clock ticks needed for us to digest is more or less set, at least locally. If we are near the clock, it will generally require N ticks for us to begin feeling alert and hungry again. But, that does not necessarily mean that a clock somewhere else will tick N times before the clock and our digestive system agree that it is time once again to eat.
It is unfortunate that students are introduced to Special Relativity as depending on relative velocity. It really does not. If, at the moment of creation, two spaceships were brought into being traveling at a constant speed toward one another, then their clocks would run at the same rate, and they would agree on the time since creation when they passed each other. But, in the real world, this relative velocity can only be achieved by one or the other or both objects accelerating away from and then toward one another. Accelerating your spaceship causes your clock to tick slower relative to an identical unaccelerated one. This is how the fabled “Twin Paradox” is resolved. In some sense, you see, accelerating through space builds up a resistance to change in time, relative to how it would have been had we not accelerated. We do not perceive the change locally, in a region which has accelerated with us. But, things have changed, relative to the region we accelerated away from.
And, therein lies the answer to your question:”How would the rocket know when to stop accellerating and instead gain mass?” It gains mass continuously as it accelerates. Its mass is still the same relative to anything which accelerated with it, but it has increased with respect to objects and observers which it left behind. And, all that means is that its trajectory relative to those observers will evolve as though its mass were the greater value.
This reply is getting pretty long-winded. Hopefully, it is of some use to you.
Bart says:
May 7, 2011 at 11:31 am
– 13.2 Mly versus 13.8 Mly should have been 13.2 Bly versus 13.8 Bly.
Bart says:
May 7, 2011 at 11:31 am
What I am perplexed by is that, I was taught that nothing could be observed beyond the Hubble radius. That’s no problem, as this object falls within the Hubble radius (13.2 Mly versus 13.8 Mly).
Because of the expansion of space we can actually see out to a distance of more than 40 Gly, because what we now see at 13 Gly was emitted 13 Gyr ago, but is now actually some 40 Gly away.
Bart,
thank you for taking the time to reply to my comments, as well as many others.
You say that both space and time are warped.
Analogies are often made of warped 2 dimensional space. These can be convex or concave, and result in geometry where the angles of a triangle do not add to 180 degrees, or the ratio of the circumference of a circle to the diameter is not pi. However, when you examine these warped planes, the result occurs because the plane is warped into the third dimension. Therefore, if 3d space is warped, it must be warped into a fourth dimension of space. The problem is, in the GR model there are only 3 dimensions of space and 1 of time.
The definitions of space being warped include the fact that the internal angle of a triangle does not add up to 180 degrees. How do you construct such a triangle? By projecting a laser beam. If it was the case that the angles did not add up to 180 degrees, it would be because gravity is bending the light beams. Is it not the case that the bending of light by gravity is being used as a proxy for bending of space? In classical Newtonian physics, the bending of light by gravity would be explained as just that – bending of light by gravity – not as warping of space. Therefore, this warping of space is just a mathematical contrivance to base geometry on the path of a light beam.
In the physical sense, space is not warped because there is no other dimension to warp it into.
Louis Savain says:
May 7, 2011 at 11:41 am
“Time cannot change by definition.”
I know… don’t feed the troll. But, I just had to chuckle at this. It reminded me of Gavin Schmidt opining on the appropriateness of global average temperature as a metric for climate change, saying ‘“Climate sensitivity” is *defined* as being the equilibrium response of the global mean surface temperature to a change in radiative forcing while holding a number of things constant…’
Science is so much easier if you can just force Nature to obey your dictates via definitional fiat.
Leif Svalgaard says:
May 7, 2011 at 12:51 pm
“Because of the expansion of space we can actually see out to a distance of more than 40 Gly, because what we now see at 13 Gly was emitted 13 Gyr ago, but is now actually some 40 Gly away.”
We cannot “see” something until the light gets here. But, I see your point. So. 0.96c*40/13 = 2.9c, which is consistent with the chart and a redshift of 10.3. But, that is an anticipatory redshift. Weird, but perhaps that is what is meant.
Bart says:
May 7, 2011 at 1:23 pm
We cannot “see” something until the light gets here.
One more time: what is now at 40 Gly we see because its light was emitted 13 Gyr ago and thus has ‘just’ got here.
Vince Causey says:
May 7, 2011 at 1:02 pm
“In the physical sense, space is not warped because there is no other dimension to warp it into.”
This was the genius of Riemann, who freed differential geometry from the confines of embedded manifolds and allowed them to be generalized into the abstract. You do not have to have another dimension to warp it into.
Here’s an analogous situation that might resonate. Consider a two dimensional surface embedded in 3-d space. Suppose you are a two dimensional being living in a seemingly infinite plane. The plane is spinning about its center of mass in 3-d space, but you don’t know that, because all you can perceive lies in the plane. All you know is that, when you are at a particular spot, you feel no force against you. But, when you move away from it, you are pushed farther away from it, and pushed harder the farther you go. To you, your space is warped, and wants to channel you in a particular direction (away from the spot).
I can’t visualise empty space being warped or bent because I don’t think it has that property ,force will pass through empty space without affecting anything.Empty space is just empty space,I can’t visualise empty space bending and causing light and matter to follow a bent path even if that is true.
Leif Svalgaard says:
May 7, 2011 at 1:51 pm
“One more time: what is now at 40 Gly we see because its light was emitted 13 Gyr ago and thus has ‘just’ got here.”
One more time: We cannot “see” something until the light gets here. The light traveled 13.2 Bly, not 40 Bly. It left the object 13.2 Byr ago.
I accept your explanation, Lief, that the Wikipedia chart is based on redshift observed from an object which was then at 13.2 Bly receding at sub-light speed versus recessional velocity now when the object has moved on to ~ 40 Bly. It just seems an odd hybrid convention to me to plot it in that way, and I wish the article had explained it.
Bart says:
May 7, 2011 at 2:18 pm
One more time: We cannot “see” something until the light gets here. The light traveled 13.2 Bly, not 40 Bly. It left the object 13.2 Byr ago.
One last time: the light is here from an object that now is 40 Glyrs away.
[snip] …The truth hurts doesn’t it, Anthony? But you can’t shut me up… [snip]
[Reply: No one is shutting you up, this is America. But if you want to say your piece here, you need to be a little less cranky. Posting on WUWT is a privilege, not a right. ~db stealey, mod.]
Vince Causey says:
May 6, 2011 at 5:46 am
You have articulated a question that I have often thought about. For what it’s worth, here’s my take on the warping of spacetime.
As I understand it – 3d space is not warped – that wouldn’t make sense.
Thanks for coming in here.
The presence of matter makes time run slower and therefore what is being warped is time. You have to think of 4d space-time that is being warped, and the warping is because of the time dimension, not the 3 spatial dimensions. A particle curves towards the Earth because time is running more slowly closer to the Earth. It is a rule of GR that a particle will move from one place to another so that a clock carried on it will show a longer time than it would on any other trajectory. This is a reason why the particle moves towards the Earth. If it didn’t do so, its clock would show a shorter time. From the framework of 4d spacetime, we say that the particle is following the shortest distance in spacetime – ie, a straight line through spacetime – and in doing so the particle moves in a curve through space, but the space itself isn’t warped.
Sorry, just to get this clear re time: “It is a rule of GR that a particle will move from one place to another so that a clock carried on it will show a longer time than it would on any other trajectory. This is the reason why the particle moves towards the Earth. If it didn’t do so, its clock would show a shorter time.
Could you elaborate please, I think you may be talking in a form of shorthand and I’m not getting the references. What do you mean by another trajectory? Is the first, the longer time, a set amount in space from say one planet to another? And the ‘any other trajectory’ just it travelling through space but not towards anything?
From the framework of 4d spacetime, we say that the particle is following the shortest distance in spacetime – ie, a straight line through spacetime – and in doing so the particle moves in a curve through space, but the space itself isn’t warped.
This is the when the particle gets to point B? So you’re saying it’s not the space which is creating the curved path, but the attraction somehow of matter which then slows down the time as the matter’s attraction brings it into a curve around it?
If I’ve understood that correctly. I think that’s still not time that is being warped, but only the speed of the particle.
Actually no, I don’t understand the first part. Do you mean re from one location to another, because it is moving the clock is slower? So if a clock is not in Earth’s gravitational field and not moving it is then faster?
The time link posted above: http://www.metaresearch.org/cosmology/gps-relativity.asp
“(GR) predicts that clocks in a stronger gravitational field will tick at a slower rate. (SR) predicts that moving clocks will appear to tick slower than non-moving ones. Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth.”
That’s still just a function of matters’ attraction/distance isn’t it? It’s a heavier body slowing down another lighter something. It’s not really altering time itself, only the speed the lighter something is moving in a space. I don’t see how that is any different from the boiling point of water, say, altering at different heights. ‘Apparently’ not cancelling out above sea level a clock on a moving plane ‘will appear’ to tick slower, but the less gravity at the height wins out and it ticks faster..
It’s the ‘appears’ which is amiss here, I think. I don’t know if you’ve ever seen the demonstration of the ‘shrinking and growing Alice’, don’t know the official title, but – a viewer outside of a room has an oblong window to look through into the room, but the field of vision is restricted, he can see the ceiling and the floor of the wall opposite him which he can see from corner to corner. He sees a person in one corner normal size to the room; that person moves along the wall to the opposite corner of the same wall – and while doing so begins to grow bigger and bigger until he is squashed as his head reaches the ceiling. Even when it is explained, how this effect is achieved, one’s mind just cannot stop seeing the same effect, because it so ingrained as a learned response to the outside world, (the floor rises from one corner to the next, so the person growing is actually walking up an incline, but we still see parallel ceiling to floor), that the mind still continues to interpret it exactly as it is seeing it even though it at the same time understands what is really happening. In other words, you can’t stop seeing the man grow until he has to bend his head at the ceiling, because our learned interpretation of the world around us is that ceilings and floors are in a particular relationship to each other. Some many years ago there was a study on perception in a wild and wooly tribe somewhere in Africa. These people did not have any learned perception of square houses, they couldn’t see them. They too could be taught that a square house was a square and not a circle, but even understanding that, they still saw a round house. Perception is a learned response in childhood. All this to say, that ‘apparently’, those long haul boring plane rides must have the same effect as heavier matter/strong gravity, it completely overrides and reverses the effect of time apparently speeding up the higher one gets away from a strong gravity at sea level..
William Mason says:
May 6, 2011 at 9:45 am
I don’t think the picture is meant to be taken literally. It is drawn that way because if you draw every possible angle in 3d you would just see a sphere of ink. It is drawn in the two dimensions so you can see the shape and once understanding the concept use your mind to apply it to the 3rd dimension.
Which I did, and I got much the same result as you get, a sphere of ink.. The only difference is you’re rejecting what you’re seeing. The picture says it’s a four dimensional representation! It doesn’t even make sense in 3.
Imagine you’re jumping on a trampoline, now extend that trampoline to be a complete sphere around you and keep jumping around making big dents in the thing. The claim is that the Earth is not jumping from one point to another, but it is impinging equally on every point of the space around it. These must either cancel each other out if the Earth is truly impinging on the trampoline/stuff/inside of balloon/honey/space around it, or, it isn’t impinging at all as that diagram purports to show.
The Earth is not two dimensional, it is 3D. If, it is impinging on it’s surroundings as in the diagram then that has to extrapolated to 3D, where each of the points on the 3D Earth must impinge massively into the surrounding equally in 3D space.
Myrrh says:
May 7, 2011 at 4:20 pm
As I understand it – 3d space is not warped – that wouldn’t make sense.
You cannot separate space from time. there is only spacetime.
“(GR) predicts that clocks in a stronger gravitational field will tick at a slower rate. (SR) predicts that moving clocks will appear to tick slower than non-moving ones. Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth.”
and this is simply not true. See e.g. here: http://www.exo.net/~pauld/physics/relativity/relativitytimefly.htm
Bart says:
May 6, 2011 at 3:27 pm
Re my: “If the mass of the Earth is warping space around it which is what is then pulling in stuff which is gravity, it can only be doing this exactly as in the diagram, on a plane. It cannot be extrapolated to three dimensions.”
Why not?
Because it has to be equally so all the way around. Which leaves no dips.
Re my: “I’m saying that can only be two dimensional, (exactly as in the diagram), because a mass will impinge itself in all directions equally, (if such a thing was happening), cancelling out all the individual impinging on all the points touching the surrounding space, in a three dimensional space.”
You need to integrate the pull over the entire mass. Gravity surrounding a spherical mass behaves externally just as though the mass were concentrated at a single point in the center.
How does it get to behave like that by the depicted scenario extrapolated to 3D?
If, the Earth is really creating such a great dent in the space around it by its mass, if it is doing so it must be equally on every point of its sphere, then there should be a layer of thick honey equally all around the Earth in a band all around at every point. The Earth the yolk of an egg, and the thick layer of stuff space/time its mass is squashing in all directions, the shell around the yolk. Is there?
Myrrh says:
May 7, 2011 at 4:45 pm
Earth must impinge massively into the surrounding equally in 3D space.
What happens is that the volume of the space inscribed by the 3D sphere is different from what you calculate for a flat space: 4pi/3*Radius^3.
Louis Savain says:
May 7, 2011 at 4:08 pm
[snip] …The truth hurts doesn’t it, Anthony? But you can’t shut me up… [snip]
[Reply: No one is shutting you up, this is America. But if you want to say your piece here, you need to be a little less cranky. Posting on WUWT is a privilege, not a right. ~db stealey, mod.]
ahahaha…
Stealy, you can kiss my you know what. WUWT commenters are calling me “troll”, “stupid” and insulting me left and right while you moderators self-righteously look the other way. And then you have the nerve to accuse me of being cranky? And all because I criticize your little god, Einstein?
And what’s up with the privilege crap? You think I need to post anything on this blog? I got news for you: you don’t put food on my table. You should all be grateful to me because I taught you something that you did not know. I did you a favor by spilling the beans on the silliness and illogic of Einstein’s spacetime on this blog. I am not the one who is privileged here. You are. You are all a bunch of ingrates and ignoramuses. You don’t deserve my good graces. Ya’ll can eat shit.
PS. I dare you to publish this with no deletions, you gutless cowards. 😀
REPLY: Oh I’ll publish it, to demonstrate the sort of person you are. But it will in fact be the last comment from you here as you’ve now violated site policy. Banned. – Anthony
Myrrh says:
May 7, 2011 at 5:19 pm
because a mass will impinge itself in all directions equally
You seem to be hung up on the ‘impinging in all directions equally’. Perhaps look at this way: the impinging from all directions is stronger the closer to the mass you are than it would be if it were not for GR. In this case you can get out from under the ‘all directions equally’ fixation.
Myrrh says:
May 7, 2011 at 5:19 pm
because a mass will impinge itself in all directions equally
Perhaps this set of lectures will help:
http://asterisk.apod.com/viewforum.php?f=39
Especially the lecture on curved spaces
Louis Savain says:
May 7, 2011 at 5:32 pm
=====
We are having a discussion here, opposing opinions are encouraged, the participants of the debate rarely resort to such vile verbiage, it shows bad manners.
(and, it is an admission that they lost the argument).
Louis Savain says: “Ya’ll can eat…”
Coprophagia is how animals keep their dens clean and reduce smells that attract preditors.
Leif says May 7, 2011 at 4:53 pm
You cannot separate space from time. There is only spacetime.
There is only stuff. You can call it what you like, but that it’s “spacetime” is unproven.
Re the “GR predicts that clocks in a stronger gravitational field will tick at a slower rate. SR predicts that moving clocks will appear to tick slower than non-moving ones. Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth.” from the http://metaresearch.org/cosmology/gps-relativity.asp
and this is simply not true. See e.g. here:
http://www.exo.net/~pauld/physics/relativity/relativitytimefly.htm
What is simply not true? I’ve read through your link, well, it’s late so maybe not so thoroughly as I should, but I can’t find what your link is saying that’s particularly different. The link I referred to was posted by PaulH I think, and I thought a very good explanation, and it appears to me, to be a better level of explanation than your link. But, anyway, please be more specific in what you’re disagreeing with, and please quote what it is that says this isn’t true from your link. Ta.
Leif says later at 5:25 pm
Re my: “Earth must impinge massively into the surrounding equally in 3D space.”
What happens is that the volume of the space inscribed by the 3D sphere is different from what you calculate for a flat space: 4pi/3*Radius^3.
I don’t know whether I’ve mentioned this specifically to you in our various exchanges, but I don’t have the maths language.. Please explain that in English if you’re making some point here.
“Inscribed” I do understand, but looked it up for geometry.. So how is that for the boundary of the Earth including boundary to this alleged eggshell of squashed space/time all around it, and then including the thickness of the squashed space/time?
Leif says: May 7, at 5:36 pm
Re my: “because a mass will impinge itself in all directions equally”
You seem to be hung up on the ‘impinging in all directions equally’. Perhaps look at this way: the impinging from all directions is stronger the closer to the mass you are than it would be if it were not for GR. In this case you can get out from under the ‘all directions equally’ fixation.
I said, “if such a thing were happening”. If you’d bother to read my post for context you’d have got that, I’ve been saying it all the way through this. The impinging in all directions equally comes from extrapolating the concept as depicted in the diagram into 3 dimensions.
Your “impinging in all directions is greater the closer to the mass you are” means what here? The alleged ‘space/time’ is immediate all around the greater mass, and the greater mass is impinging into it enough you say to alter by dramatically bending it out of shape deeply enough to create gravity.
Myrrh says:
May 7, 2011 at 6:30 pm
There is only stuff. You can call it what you like, but that it’s “spacetime” is unproven.
The stuff there is is called spacetime and have the properties specified by the special theory of relativity: that two observers moving relative to each other will disagree on the space between two event and on the timing of the events. They will, however, agree on the distance between the two events in spacetime. This is a fact. If you cannot stomach that the discussion is dead to begin with.
What is simply not true?
That the two effect cancel out exactly.
please be more specific in what you’re disagreeing with, and please quote what it is that says this isn’t true from your link. Ta.
Simply flying clocks around the Earth shows the effects do not cancel out.
Please explain that in English if you’re making some point here.
That the ‘impinging’ [which I don’t quite know what you think is] being the same from all directions is relevant. Space is simply curved equally in all directions around a mass.
So how is that for the boundary of the Earth including boundary to this alleged eggshell of squashed space/time all around it, and then including the thickness of the squashed space/time?
Not sure what you mean, but the shell can be thought of as being infinitely thin and there being infinitely many of them. The curvature of spacetime gets larger and larger the closer to the mass you are in all directions equally. In Newton’s world there is no curvature, but a mysterious force called gravity reaches out through space instantly and works at a distance [any distance from here to infinity] without any coupling, mechanism, or actor. In Einstein’s [and our] world there is no such force and no mechanism is needed. Mass just determines the curvature of spacetime locally. BTW, on very large scales [greater than galaxies] spacetime is flat [observations show this].
Myrrh says:
May 7, 2011 at 6:57 pm
the greater mass is impinging into it enough you say to alter by dramatically bending it out of shape deeply enough to create gravity.
Yes, perhaps this is the way you could understand this. Mass bends [curves] spacetime to create [the illusion of a force of] gravity. As simple as that. Sometimes, people have the hardest time understanding very simple things. Einstein fought against that attitude all this life. Only after his death was general relativity serious physics. He didn’t even get the Nobel Prize for GR.
Leif Svalgaard says:
May 7, 2011 at 3:23 pm
One last time: the light never traveled 40 Bly to reach us &_&.
Myrrh says:
May 7, 2011 at 4:20 pm
“The presence of matter makes time run slower and therefore what is being warped is time.”
Both space and time are warped about a massive object. Overall, I think a large part of the problem you are having is semantic. What do you think it means, for space and time to be “warped”? All it means is time and the dimensions of space do not maintain the same relationship to one another which they would in the absence of a massive body nearby. Which means that bodies move differently, and processes occur at different rates relative to others, than they normally would.
Louis Savain says:
May 7, 2011 at 5:32 pm
You can’t respond, but you can read. Maybe it would help your case if you could show how to design a Doppler radar, or get consistent measurements from a GPS satellite, WITHOUT using Relativity. When you are able to do so, give us a call. In the meantime, these and other properties explained by the theory can be put to many good uses.
In a way, your task is only half as difficult as it appears. Whatever you might come up with, it must have the same form as the equations derived from relativistic principles, because these have been verified repeatedly to exacting accuracies. You just have to come up with another explanation for how they come about.
Bart says:
May 7, 2011 at 8:10 pm
One last time: the light never traveled 40 Bly to reach us &_&.
Nobody is saying that. I’m saying that we are seeing [just took a photograph of it] a galaxy that is now 40 Gly away, so we can obviously see that far.
Leif – But, what we are “seeing” is not the galaxy now at 40 Bly, it is the galaxy then (13.2 Byr ago at 13.2 Bly), so we are not seeing a galaxy 40 Bly away, any more than I have seen the men and women who grew up from the boys and girls I knew in grade school, but with whom I lost touch along the way.
This discussion is a little vexing to me because it’s not what I am interested in. It appears we are asking different questions. This is mine: The article says the distance to the galaxy at the time the photons which have been collected were released is 13.2 Bly. At that time, Hubble’s relation tells me the object was receding at 0.96c. The graph at Wikipedia says that would produce a redshift of roughly unity. However, the article says the redshift is more like 10, which the graph says corresponds to a velocity of around 2c.
OK. So, my question is, did they actually measure a redshift of about 1 and extrapolate that to a redshift of about 10 for photons emitted but not yet observed based on where the object is now, or did they actually measure a redshift of 10 and the Wiki graph is plotting velocity now versus redshift of a photon emitted then? Either way, it is confusing, though conventions often can be until you get used to them.
My GR training ended after the standard three elementary solutions for the metric external to a massive body (Schwarzschild, Reissner-Nordstrom, Kerr), and a very brief overview of cosmology, so I do not know the conventions someone in the field would use, or what a typical redshift is versus distance to the source.
Bart says:
May 8, 2011 at 12:12 am
what we are “seeing” is not the galaxy now at 40 Bly, it is the galaxy then (13.2 Byr ago at 13.2 Bly), so we are not seeing a galaxy 40 Bly away
We are seeing a galaxy that now is 40 Gly away.
The article says the distance to the galaxy at the time the photons which have been collected were released is 13.2 Bly. At that time, Hubble’s relation tells me the object was receding at 0.96c.
Perhaps you are confusing light years and parsecs….
did they actually measure a redshift of 10
The measured redshift is ~10.
>>
Bart says:
May 6, 2011 at 3:27 pm
Jim Masterson says:
May 5, 2011 at 1:23 am
“It’s harder to show mathematically, but a ring can’t orbit around a star either (as in Ringworld).”
But, it can remain steadily oriented in space through gyroscopic stiffness, and its CG will move approximately with the Star’s CG. Some stationkeeping may be needed to deal with stray forces which act differently on the Star and the ring.
<<
We’re talking about a structure (made of metal? silicon? Niven, of course, made up some fantasy-super-strong material to build the ring with.) that is two astronomical units across and about a million miles wide. I doubt seriously that such a structure would be rigid enough to rotate with “gyroscopic stiffness.” The “station-keeping” would be quite a feat by itself.
But let’s do some calculations. The Earth must travel fast enough to orbit the Sun in one year. (We can assume the orbit is circular to simplify the calculation.) This gives us an average orbital speed of 2*pi*AU/year-in-seconds = 29.79 km/sec.
To compare, the escape velocity from the Earth is 25,000 miles/hour or 11.2 km/sec. So the Earth is orbiting the Sun at more than 2.5 times the fastest speed that man has yet traveled (escape velocity was required to reach the Moon).
Ringworld rotated fast enough to create about 1 g. Let’s try to calculate that. Centripetal acceleration is: a = v^2/r where a is 1 g or 9.8 m/sec^2 and r is 1 AU or 149,597,870.691 km. Solving for v we get 1210.8 km/sec. This is about 40 times the velocity required to counteract the Sun’s gravitational force. The ring would make one rotation in about 9 days. I doubt that such a structure could withstand the centrifugal force and would fly apart.
Jim
Leif says:
May 7, 2011 at 7:08
Re my: “There is only stuff. You can call it what you like, but that it’s “spacetime” is unproven.”
The stuff there is called spacetime and have the properties specified by the special theory of relativity: that two observers moving relative to each other will disagree on the space between two events and on the timing of the events. They will, however, agree on the distance between the two events in spacetime. This is a fact. If you cannot stomach that the discussion is dead to begin with.
What you’re not dealing with here is that “spacetime” is still unproven. These things may well happen, I don’t have the time to go into more complicated effects witnessed in our world, but you still haven’t proved that it is your “spacetime” that is doing this, that it even exists, that the method claimed is warping it is even possible!
So, as I originally asked, first prove that such a warping exists of the space around the Earth, is even possible, in 3D, before invoking time.
There is nothing in that diagram that shows Time being warped or that it is even involved. Claiming it is a representation of 4 dimensions is nonsense. It represents a claimed scenario in simple 3D, of the body with mass affecting the space around it.
From now on I shall try to remember to refer to this space stuff as honey stuff or space honey, to root it firmly into the 3D problem that this diagram is actually representing and rooting it firmly into the description of it from the experimenters. When I forget I’ll revert to space or stuff.
Re my: “What is simply not true?”
that the two effects cancel out exactly.
Still can’t find it. Please point it out.
Re my: “please be more specific in what you’re disagreeing with, and please quote what it is that says this isn’t true from you link. Ta.”
Simply flying clocks around the Earth shows the effects do not cancel out.
Still can’t find it saying that. It does however say that it is not dealing with General Relativity on that web page – are you confusing this because you haven’t taken that into account?
Re my “Please explain that in English if you’re making some point here.”
That the ‘impinging’ [which I don’t quite know what you think is] being the same from all directions is relevant. Space is simply curved equally in all directions around a mass.
The impinging as in the diagram. That the mass of the Earth is sinking into the honey space is it impinging on it. As the general description of this gives it, take a rubber sheet and put a heavy round ball in the middle of it, and the weight of the ball distorts the rubber sheet – it impinges on it, impacts upon it. (COD) impinge – v.t. and t. (Cause to) make impact (on, upon); hence ~ment n.
Re my: “So how is that for the boundary of the Earth including boundary to this alledged eggshell of squashed space/time all around it, and then including the thickness of the squashed space/time?”
Not sure what you mean, but the shell can be thought of as being infinitely thin and there being infinitely many of them. The curvature of spacetime gets larger and larger the closer to the mass you are in all directions equally.
[So you agree that it is equally in all directions, therefore making it a simple 3D model as the diagram is extrapolated all around equally.] By the shell I mean at the deepest point of each impingement/impact of the heavy body into the spacehoney surrounding it, which then extrapolated all around the body equally would create a shell around it, the edge between the unwarped honeyspace and the warped at every point of the deepest effect of the mass impacting/impinging on it. As in the diagram. Because the Earth is distorting a something there is a squashed area at the deepest point beyond which the distortion doesn’t go, while the honeyspace around that point is slipping around the weight distorting it into less curvature. The Earth then has this shell of more compacted honeyspace directly at each point as the mass impacts it.
Which is what you are also saying in the “the shell can be thought of … there being infinitely many of them, and “the curvature of spacetime gets larger and larger the closer to the mass you are in all directions equally”.
So, the further away the more honeyspace’s distortion becomes less, the curvature straightening out until it is just honeyspace undistorted by the mass of the body. By boundaries I mean the beginning of the outside edge point which is the shell at the last moment of greatest distortion into the honey space, to when the weight/mass of the body is no longer capable of distorting it and it reverts to undistorted; the beginning and end of the shell which is the amount of the distortion the body creates by its impact at its deepest effect. In the diagram the beginning of the space between the earth and the furthest point of the reach of its effect on the space honey it is distorting. So, the Earth is completely enclosed by this shell, there is no more opening on the other side of Earth to the point at which its mass is distorting the space on its opposite point. No open curvature spiralling in anywhere on the shell to capture anything supposedly travelling in a straight line and claiming this is gravity. It has all been cancelled out. Even if you could show that this was a one way street and the honey stuff was merely being acted on and not also acting on the body distorting it, there is no warp. There’s nothing happening from the distortion created by the mass because it’s the same all the way around.
So, what we’re left with is the normal 3D effect of a body suspended in a fluid.
And all the experimenters have found, is that the spin of the Earth is moving this fluid space honey.
Now, if you want a vortex out of that then perhaps you should look to the movement of fluids on Earth. Down the plug hole with different spins in each hemisphere. So not some mythical “space/time” invisibly channeling in something travelling in a straight line which just happens to get caught at the top of a helterskelter, but the Earth extending its reach into the honey stuff all around it and sucking that in, taking with it whatever has been caught in the fluid… Where’s it all going?! Hmm, the Earth must be recycling it somehow. Earth is the Honey Monster..
Anyway, the Earth is also moving as well as spinning, and at the boundary layer of a body moving fast in a fluid we have well understood science too: http://hkprogolf.com/dimples.html
[Air is a gas, Air and Water are fluids.]
From which about a golf ball travelling at around 120 miles an hour:
So, at the surface of the Earth moving around the Sun in a fluid honey space stuff which you call space/time, the fluid space is still, and in the boundary layer it is just slurping along creating wild whipping whirlpools as the fluid space tumbles behind the speeding Earth, and just above that, the fluid space is rushing past the much slower moving slurpy honey stuff.
So, the spinning Earth in the fluid space stuff around it like a golf ball with a spin on it travelling at speed through the fluid gas Air. We know the effects of this, as described above and continued on that page. Normal Science can work out the drag, the low pressure formed behind the Earth taking into account its speed and size and so on.
Your scenario, of a static bending of space stuff around the Earth, has no means of capturing anything because all it creates is a closed boundary layer, of a ball suspended in a bath of water. Not even taking into account that such a ball is also being acted upon by the water surrounding it.
Your scenario is incapable of explaining 3D space around it, and yet you claim this also includes Time…
And lastly, from http://www.docstoc.com/docs/6077410/Gravitational_field
Hmm, seems to me that ‘the ether’ is just what this honey is, and the Earth moving in it and spinning it around fully capable of being explained by bog standard science of 3D reality as the golf ball is explained.
Does this experiment then, prove the Ether theory?
Myrrh says:
May 8, 2011 at 10:39 am
Dealing with here is that “spacetime” is still unproven. These things may well happen, I don’t have the time to go into more complicated effects witnessed in our world, but you still haven’t proved that it is your “spacetime” that is doing this, that it even exists, that the method claimed is warping it is even possible!
All my links have not had any effect, it seems. Spacetime is one of the best supported fact of all of science.
It represents a claimed scenario in simple 3D, of the body with mass affecting the space around it.
spacetime is curved.
Re my: “What is simply not true?”
that the two effects cancel out exactly.
Still can’t find it. Please point it out.
Myrrh says:
May 7, 2011 at 4:20 pm
“Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth.”
and this is simply not true.
Because the Earth is distorting a something there is a squashed area at the deepest point
Not a squashed area, but a squashed spacetime
And all the experimenters have found, is that the spin of the Earth is moving this fluid space honey.
Not only that, but also that the dragging is just what is predicted from GR’s warping of spacetime.
we have well understood science too: http://hkprogolf.com/dimples.html
Relativity is very well understood science, and has survived every experimental test it has been carried out over the last 100 years.
[Air is a gas, Air and Water are fluids.]
From which about a golf ball travelling at around 120 miles an hour:
So, the spinning Earth in the fluid space stuff around it like a golf ball with a spin on it travelling at speed through the fluid gas Air. We know the effects of this, as described above and continued on that page. Normal Science can work out the drag, the low pressure formed behind the Earth taking into account its speed and size and so on.
Relativity is Normal Science and does indeed account [quantitatively] for the observed effects.
“The detection of gravitational waves bears directly on the question of whether there is any such thing as a “gravitational field”, which can act as an independent entity. ..this fundamental field hypthesis has been generally accepted without observational support. Such credulity among scientists occurs only in relation to the deepest and most fundamental hypotheses for which they lack the facility to think differently in a comparably detailed and consistent way. In the nineteenth century a similar attitude led to a general acceptance of the ether..”
The pulses from binary pulsars are slowed down by their issuance of gravitational waves, e.g. http://en.wikipedia.org/wiki/Gravitational_wave Detectors are being constructed both on Earth and in Space and we are approaching the sensitivity needed to detect the waves directly.
Does this experiment then, prove the Ether theory?
In a sense, yes. In another sense, no [not the classical Ether theory]: http://redshift.vif.com/BookBlurbs/PIRTVol1.htm
Bart says:
May 7, 2011 at 8:10 pm
Myrrh says: May 7, 2011 at 4:20 pm
“The presence of matter makes time run slower and therefore what is being warped is time.”
Not me, I was quoting Vince Causey, who first said that he agrees it is not space being warped, but thinks matter is warping time (so the discussion on moving objects apparently slowing down time etc.
So to Vince’s statement thinking it mine you reply:
Both space and time are warped about a massive object. Overall, I think a large part of the problem you are having is semantic. What do you think it means for space and time to “warped”? All it means is time and the dimensions of space do not maintain the same relationship to one another which they would in the absence of a massive body nearby. Which means that bodies move differently, and processes occur at different rates relative to others, than they normally would.
What I mean by space and time to be “warped” is exactly as it is presented by you, generic, in the diagram which begins this discussion. That is what I am describing and commenting on.
The rest of your paragraph continuing “All it means..”, is hypothetical. I’m saying that you can’t even make that diagram work in 3D reality, so how the heck do you think you can establish that any kind of difference exists between your hypothetical measurements invoking Time relating to Space with a massive body nearby when your concept of Time and Space without a massive body nearby isn’t proven to exist and when your concept of a massive body distorting ‘space/time’ all around it creates a simple ball suspended in a bath of still water, at best?
See my last post to Leif.
Leif Svalgaard says:
May 8, 2011 at 1:51 am
“We are seeing a galaxy that now is 40 Gly away.”
I’m going to leave this alone, because the horse is long dead.
“Perhaps you are confusing light years and parsecs….”
Actually, recessional velocity must have been sub-light at that time because it is below the Hubble radius of 13.8 Bly and, otherwise, the light would not have gotten to us. But, the calculation is simple enough. Hubble’s constant is about 71 km/sec/Mpc. A parsec is 3.26 ly. Speed of light is 300e3 km/sec. Recessional velocity is (was) 71*13.2e9/3.26e6/300e3 c = 0.96c.
“The measured redshift is ~10.”
In that case, barring any additional information, I assume the Wiki graph is plotting velocity now versus redshift of a photon emitted then. That’s fine. It’s just a convention. But, I wish they had made it clear in presenting the graph.
Jim Masterson says:
May 8, 2011 at 8:22 am
“I doubt that such a structure could withstand the centrifugal force and would fly apart.”
I think you need to give this some more thought. Centrifugal “force” is mass times centripetal acceleration. How difficult is it to find materials which will stand up to that kind of g-load?
Myrrh says:
May 8, 2011 at 10:39 am
“There is nothing in that diagram that shows Time being warped or that it is even involved. Claiming it is a representation of 4 dimensions is nonsense. It represents a claimed scenario in simple 3D, of the body with mass affecting the space around it.”
It is NOT a representation, it is an analogy. It does not represent anything in 3D. It represents something in 2D which is analogous to the situation in 4D. You are taking this analogy WAY too literally.
“What you’re not dealing with here is that “spacetime” is still unproven.”
It gives us results which are replicable and repeatable in the real world, and allow us to design neat stuff like Doppler radar and GPS systems. If you don’t like it, that’s your personal preference. But, it’s not going to stop the rest of us from exploiting its predictions.
Leif Svalgaard says:
May 8, 2011 at 11:10 am
“Re my: “What is simply not true?”
that the two effects cancel out exactly.
Still can’t find it. Please point it out.
Myrrh says:
May 7, 2011 at 4:20 pm
“Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth.”
and this is simply not true.”
The claim in Myrrh’s reference was not anything as general as he thinks or you have accepted. It is making a very narrow claim, which is this: time runs slower at the poles of the Earth than it does at the equator due to the fact that the radius of the Earth is smaller there (GR effect). But, it runs slower at the equator than it does at the poles because of the velocity of a point on the equator is greater than the velocity of a point at either pole (SR effect). It is claimed that the two effects roughly cancel each other out. Maybe so – I have not done the calculation though, and am not endorsing it until I have.
Myrrh says:
May 8, 2011 at 11:11 am
“What I mean by space and time to be “warped” is exactly as it is presented by you, generic, in the diagram which begins this discussion. That is what I am describing and commenting on.”
Stop. Please, stop. It is an analogy which has failed to give you the desired insight. It is not IN ANY WAY a rigorous explanation of what is happening in 4D spacetime.
Bart says:
May 8, 2011 at 11:42 am
Leif Svalgaard says:
May 8, 2011 at 11:10 am
Let me make this a little clearer…
“It is claimed that the two effects roughly cancel each other out over the oblate spheroid of the Earth regardless of latitude. The slower the time from GR, the faster from SR in roughly equal measure and vice versa.
Bart says:
May 8, 2011 at 11:51 am
Bart says:
May 8, 2011 at 11:42 am
Leif Svalgaard says:
May 8, 2011 at 11:10 am
Let me make this even more clear…
The point is that time is roughly uniform in rate over the surface of the Earth. It says nothing about the rate of time on the surface of the Earth versus anywhere else.
I’ll reply to Leif and Bart tomorrow. Meanwhile, for our delectation or consternation depending on one’s view, it’s all relative ain’t it, something I’ve just found while reading this site’s pages:
http://einstein.stanford.edu/SPACETIME/spacetime4.html
As several have mentioned and in several different ways, the experiment’s claim to have proved two of Einstein’s theories has had to be tortured out of the data gathered and even that not done very well..
Why not just admit it? There’s nothing here, after 52 years of experimental data collection, that can’t be explained in bog standard 3D movement of bodies in a fluid, curvature included.
http://einstein.stanford.edu/SPACETIME/spacetime3.html
And doesn’t make any sense elsewhere in science knowledge.
Savin was right istm, what has been happening is that the equations work where they do because they revert back to Newton or other known effects, that is, can be explained otherwise than by the claim that it is this entity ‘spacetime’ being warped by matter as the cause of ‘relativity’ and whenever it is tried to prove that this is alone the cause there is only failure to produce the evidence.
Perhaps an interesting experiment in trying to measure perception, but like the man who mistook his wife for a hat, what then does he make of it when he sees a real hat?
So, Yang was right.
To mods, much appreciated.
“There’s nothing here, after 52 years of experimental data collection, that can’t be explained in bog standard 3D movement of bodies in a fluid, curvature included.”
No, Myrrh, that just isn’t the case. Newtonian mechanics doesn’t explain the bending of light via gravitational lensing. It doesn’t explain the cosmological and gravitational redshifts. It doesn’t explain the precession of the perihelion of Mercury. It doesn’t explain the loss of output energy from binary pulsars. It doesn’t explain the clock trends on satellites and experimental aircraft.
That researchers are looking for chinks in the armor of General Relativity should come as no surprise. But, so far, none have been found. And, it is no reason to throw out all the results which have been confirmed when we can make such good use of them.
It is true that the frontiers are uncertain, and something even better may replace General Relativity as the leading theory of gravity someday. But, if so, it will simply extend General Relativity in the same way General Relativity extends Newtonian mechanics. At worst, all that will change is the interpretations, but not the formulas.
Myrrh:
I am making a comment in hope of clearing a log-jam in the interesting discussion you are having with Lief. My intention is to reduce misunderstanding that is hindering communication, but if it does not then please ignore this post.
At May 8, 2011 at 10:39 am you say in response to a comment from to Leif:
“What you’re not dealing with here is that “spacetime” is still unproven. These things may well happen, I don’t have the time to go into more complicated effects witnessed in our world, but you still haven’t proved that it is your “spacetime” that is doing this, that it even exists, that the method claimed is warping it is even possible!”
OK. But it does not matter if “spacetime is still unproven”. Indeed, it does not matter if spacetime exists other than as a useful concept.
Spacetime is an idea about the nature of the universe, and that idea can be accurately described mathemnatically. The mathematics enable predictions of behaviours in the universe and – to date – every such prediction which could be tested has been shown to be correct. Several of the predictions are counter-intuitive so the findings that they are correct is strong supporting evidence that the idea is correct.
So, the idea of spacetime is the best description of the behaviour of the universe that we have. This does not mean that spacetime exists in reality (although I and many others think it does). However, the concept of spacetime will continue to be used until we obtain a better description of how the universe behaves.
Please note that there is reason to doubt the existence of spacetime: viz. at very small scales the predictions provided by spacetime (i.e. the description of the universe provided by the idea of spacetime) do not apply and the rules of quantum mechanics apply.
In summation, spacetime is a very useful concept as a tool for describing the behaviour of the universe (at large scales), and it is not relevant to its usefulness whether or not spacetime actually exists.
I sincerely hope this helps.
Richard
Myrrh,
Forgive me if I’m wrong, but you seem to perceive the trampoline as a repesentation of the field around the Earth, such that when you envisage a multitude of these you claim they cancel each other out.
But the trampoline is a contrivance by which to imitate the gravitational slope, and is merely a projection of what is taking place on a plane passing through the centre of the Earth. Such a plane coincident with the equator should show some twisting, the effect of drag in the direction of rotation. One difference however, would be that unlike the trampoline above which shows a sharp kink or dragpause, the drag should diminish with the square of the distance and extend as far as the gravitopause, assuming there is such a thing.
Another plane at 90 degrees to the equator will be distorted into a wave shape (by the swirling honey) and thus show a different representation of the effect of drag in the direction of rotation. Likewise, every plane in between will be different, but each will show the drag from its own perspective and none will cancel out.
I hope this helps you not to take the trampoline so literally.
wayne says:
May 6, 2011 at 9:55 pm
“No, I wasn’t speaking of field density but acceleration.”
Well that’s fine if acceleration is what you meant, but it ain’t what you said. viz: “Don’t look at that green-blue mesh and think that is what the real signature of Earth’s gravitational field would actually look like, well, kind of, but not correct. At the center of the Earth there is no gravity field, zero.”
So I would agree with your dimple wrt acceleration, but not for field density which I maintain should be at maximum at the centre of the Earth.
“You think it would be at maximum but I know there is none at the center, in fact, no such field exists at all.”
Weightlessness is not an indication of zero field strength, but rather that forces are balanced out, as with an astronaut in orbit where he is most certainly under the influence of gravity. Gravity is maxed at the centre because mass is maxed at the centre, regardless of whether gravity is real or just a mathematical construct.
Slacko says:
May 8, 2011 at 10:47 pm
Gravity is maxed at the centre because mass is maxed at the centre, regardless of whether gravity is real or just a mathematical construct.
No, gravity is zero at the center, because gravity inside a small sphere [shrink it down to zero size at the center] only depends on the mass inside the sphere and not on the infinite mass outside the sphere. Already Newton knew this. Today this is known as Birkhoff’s theorem because it also holds in General Relativity.
Gravity will not pull you down any further then the centre of the Earth if you could fall that far at this point the gravitational force is balanced if you overshot the centre you would be pulled back.I think that the strength of gravity would be determined by the amount of total mass mostly if you were in the centre of a massive planet you would be crushed flat I think.
don penman says:
May 9, 2011 at 2:26 pm
if you were in the centre of a massive planet you would be crushed flat I think.
If you drilled a tunnel all the way through a massive planet [assuming that you could make the walls strong enough that the tunnel wouldn’t collapse] and dropped down the tunnel, you would find no gravity at the center and not be crushed.
Leif Svalgaard says:
May 8, 2011 at 11.10 am
Re my “Dealing with here is that “spacetime” is still unproven.”
All my links have not had any effect, it seems. Spacetime is one of the best supported fact of all of science.
So, where’s the proof that it exists?
I’ve looked at a lot of pages now. Odd, but no explanation of “spacetime”, no explanation of how “time” is actually warped, actually, zilch. And, I’m beginning to agree with someone who commented above about your responses, that you don’t actually engage in discussing the points. I too find you deflect by passing on to “your links” as if the answer to my question is to be found there, and regardless I’ve said that it isn’t, you keep doing it. Moreover, when I’ve called you on a specific point from your links, you ignore it, or continue your what is now becoming very rude deflection in its own right, but it still comes coupled with your condescending arrogance as you’ve just shown again.
My view, is you don’t know. You’ve probably never thought about it and have nothing to say, or you don’t understand it. Actually, probably the latter, because you so consistently avoid engaging in my actual points.
So come on Leif, show me a real explanation of “spacetime” proven as a fact.
Re my “It represents a claimed scenario in simple 3D, of the body with mass affecting the space around it.
spacetime is curved.
Yeah, yeah.
Re my “What is simply not true?”
that the two effects cancel out exactly.
followed by my: “Still can’t find it. Please point it out.”
So, Leif, you then post the original as here, where I am quoting from a link which looks comprehensive about GPS, originally posted by PaulH above:
Myrrh says:
May 7, 2011 at 4:20 pm
“Remarkably, these two effects cancel each other for clocks located at sea level anywhere on Earth.”
and this is simply not true.
So Leif, the first time around you added a link to a page to prove what you said, that this my quote was not true. You have deflected my requests since then to show me exactly from the page you linked to which supposedly proves that this is not true. You have avoided doing it, and now, you insult me even further by repeating your original statement instead of showing me on the page you linked to, where exactly it proves that what the quote is saying is not true.
Your replies are a joke. Now who was it who noted that here? Ah yes, Alexander Feht on May 5, 2011 at 11:29 pm http://wattsupwiththat.com/2011/05/04/einstein-proven-right-again/#comment-654098
“In many cases, Dr. Svalgaard doesn’t give meaningful answers or explanations. Actual intellectual content of his posts, if you look beyond the obfuscating jargon and painful reiterations of the obvious, is difficult to discern.
Dr. Svalgaard repeats textbook definitions and/or gives you a link to a Wikipedia article that contais a textbook definition – or, if you insist on clarification, pretends to misunderstand your question ..”
I now have ample proof Leif, that Alexander got you down to a t.
And as I wondered, in this particular example here, whether you were confused by the fact that general relativity wasn’t being explained on the link you posted to avoid answering me and by your continuing deliberate avoidance to engage with my asking you explain what you meant, and, with a confusion you showed earlier in this discussion about what speeds up when, I think you don’t know. Like Alexander said. You’re covering this ignorance with some very heavy footwork, tedious statements and deflections to links and avoidance of direct engagement with particular points, and your rudeness runs all the way through it.
So I won’t bother with replying to the rest of your post.
REPLY: “Myrhh” try stepping out from behind the curtain if you want some respect. Leif probably doesn’t want to engage you because you aren’t worth all the time, as your style typically becomes argumentum ad infinitum. I wouldn’t respond much either. I’m really growing tired of moderatingyour thread disruption and insults. It is becoming tedious. For now, you are in the troll bin, all posts get an extra level of inspections, and some like this one, with insults, won’t be posted. clean up your act a bit. Be as upset as you wish, but don’t put it to words. – Anthony
Myrrh says:
May 9, 2011 at 3:22 pm
“Spacetime is one of the best supported fact of all of science.”
So, where’s the proof that it exists?
Anthony is right, it is becoming tedious.
Perhaps a movie would be better for you: http://www.youtube.com/watch?v=AZ6N85lNgHY&feature=related
Bart says:
May 8, 2011 at 4:14 pm
Re my “There’s nothing here, after 52 years of experimental data collection, that can’t be explained in bog standard 3D movement of bodies in a fluid, curvature included.”
No, Myrrh, that just isn’t the case. Newtonian mechanics doesn’t explain the bending of light via gravitational lensing. It doesn’t explain the cosmological and gravitational redshifts. It doesn’t explain the precession of the perihelion of Mercury. It doesn’t explain the loss of output of energy from binary pulsars. It doesn’t explain the clock trends on satellites and experimental aircraft.
As I noted above, Einstein went back to Newton for basics, but I’m not arguing Newton v Einstein. I’m arguing that “spacetime” is just another name for the space surrounding Earth and that, including ‘gravitational lensing’, istm, can be explained by simple 3D bog standard knowledge of bodies in fluids at speed, etc. As for the clocks, they’re mechanical… But seriously, molecules in Air move considerably more slowly under gravity and Air pressure, what’s the difference? That doesn’t mean “Time” has slowed down… ..that someone won’t age as fast in space as they would on the ground, do all the molecules in the body slow down in aging? Or just in efficiency?
Again, you’re saying things that are still not actually proven, redshifts are still under debate and there have been a lot of comments too above which have noted such and rather a lot that have noted this experiment likewise has not actually proven anything. Yet the claim is that is has confirmed two of Einstein’s whatevers. Where?!
And several have noted that this ‘honey’ is just normal space as fluid affected by mass, so for curvature, please, read my golf ball in flight link, and my failed attempts to engage with Leif about boundaries, what’s different about how the mass of the golf ball reacts with the fluid gas Air around it and what these experimenters have actually found that there is this fluid honey around Earth? Only the size.
That researchers are looking for chinks in the armor of General Relativity should come as no surprise. But, so far, none have been found. And, it is no reason to throw out all the results which have been confirmed when we can make such good use of them.
Well, sorry, I’ve read that quite a lot have been found.. But, that some equations work is not what I’m arguing against, I’m arguing that the explanation behind the equations can’t be real fact in our 3D world, that this concept of “Time” in relativity doesn’t make sense, and please, do give me some actual good explanation and verified data that it is actually “Time” that is being warped if you have it. All this can be explained by our normal understanding of states of matter. It’s staring us all in the face that this experiment has shown that the space around us in which the Earth and all the planets move is a FLUID, because it moves like a fluid as do liquids and gases. Not a static/expanding ‘something’ called ‘spacetime’, which so far, have you found all the missing matter yet? no one can explain what it is. And yet the claim is that this is actually including Time itself!
Have you ever felt Time slow down? I have, when I found myself about to crash into another car which decided to overtake the cars in his lane and so coming straight at me down the hill where I was in the overtaking lane doing 70 going up, and the lane to my left was crowded. From the moment I saw the whites of his eyes and realised he had no answer..
I aged faster …
It is true that the frontiers are uncertain, and something even better may replace General Relativity as the leading theory of gravity someday. But, if so, it will simply extend General Relativity in the same wya Gerneral Relativity extends Newtonian mechanics. At worst all that will change is the interpretations, but not the formulas.
Right, and it’s the interpretations I’m looking at. And when I began, in this actual discussion, it was because the concepts behind ‘spacetime’ and the diagram and example of the Earth squashing it and so altering both space and ‘Time’ were never forthcoming whenever I’ve seen them before. This was my first opportunity to actually question anyone on this.
I’m rather pleased with my investigation so far. Thanks for discussing it.
Lief:
I understand your frustration.
It seems to me that Myrrh fails to understand that all scientific descriptions are models. Every scientist knows that any model may be modified or replaced in future. But many non-scientists think that a scientific description is THE WAY IT IS.
The space-time continuum is one of the best models we have. As you have repeatedly said, it is an excellent model in that it both explained existing observations which Newtonian mechanics could not (e.g. perturbation of Mercury’s orbit) and predicted effects that were subsequently discovered (e.g. time dilation in a gravity field). And all attempts to obtain observations which contradict it have failed.
Now the space-time continuum may be THE WAY IT IS or it may not. But so what? It is one of the best models we have, and a scientist is only interested in whether a model is a good and useful description: the space-time continuum is one of the best models we have.
Myrrh’s posts indicate he wants proof that the space-time continuum is THE WAY IT IS, but no scientist can provide such a proof of any model. Hence, I understand both your and his frustrations.
Richard
Richard S Courney says:
May 8, 2011 at 5:43 pm
Thank you for your post, yes it does help.
Several of the predictions are counter-intuitive so the findings that they are correct is strong supporting evidence that the idea is correct.
There’s counter-intuitive and counter-intuitive, I’m still amazed that anyone worked out that the Earth revolves around the Sun. But I can’t see anywhere in any of the explanations that actual Time is taken into real consideration, the descriptions are only of bog standard space, and, as I’ve discovered since joining in the discussion here, that explains it consistent with the knowledge we’ve gained in science about masses and fluids and speeds.
I think, I’m concluding, that all General Relativity re gravity can be explained as our 3D world happening in Time and such things as the clocks slowing is consistent with our now normal understanding of how matter is affected by pressure and gravity. Time itself doesn’t actually change in this just the mechanical slowing down or speeding up relative to gravity and pressure and so on, but also, the speed at which we perceive time can change dramatically. A bat lives and flits about our world as if wholly in our time and mostly it is, but if you listen with bat ears all the sounds we hear at our speed are much slower for a bat, much more drawn out. Time still hasn’t changed, just some things work in different times and so on. What we don’t know is what Time is.
Please note that there is reason to doubt the existence of spacetime: viz. at very small scales the predictions provided by spacetime (i.e. the description of the universe provided by the idea of spacetime) do not apply and the rules of quantum mechanics apply.
I’ve noted, though I haven’t read enough yet of the differences or sure that I understand qm enough to judge anyway, that there’s not the same disjunct between quantum mechanics and what is already known as there is between qm and the spacetime universe. I’ve found an example of what I mean here:
http://www.nhn.ou.edu/~kieran/reuhome/vizqm/2schroeq.htm
“When considering objects as small as electrons, the equivalent to Newton’s Laws is an equation which was originally written down by Erwin Schrodinger. This equation cannot be derived from any funamental law but is based on several well established principles of physics.”
Seems to me that qm is building on what we already know well, a progression in our understanding, and I think that if the fluidity of space was to replace the spacetime concept, that things would fall into place from it in explaining such stuff as curvature and clocks. The right tool for the job?
“
Richard S Courtney says:
May 9, 2011 at 5:23 pm
Myrrh’s posts indicate he wants proof that the space-time continuum is THE WAY IT IS
He is quite right that I do not know THE WAY IT IS. Nobody does. It is an undefined concept. To prove that a rock on the ground exists I give it hard kick. If my big toe hurts I accept that the rock exists and that that is the WAY IT IS. Freely after:
“57. Refutation of Bishop Berkeley
After we came out of the church, we stood talking for some time together of Bishop Berkeley’s ingenious sophistry to prove the nonexistence of matter, and that every thing in the universe is merely ideal. I observed, that though we are satisfied his doctrine is not true, it is impossible to refute it. I never shall forget the alacrity with which Johnson answered, striking his foot with mighty force against a large stone, till he rebounded from it — “I refute it thus.”
Boswell: Life”
Myrrh says:
May 9, 2011 at 5:24 pm
But I can’t see anywhere in any of the explanations that actual Time is taken into real consideration
What is ‘actual Time’ then? Try to express that. My and any other scientists definition is that time is what a clock shows. If that is not ‘actual’, then what is?
Myrrh says:
May 9, 2011 at 5:24 pm
But I can’t see anywhere in any of the explanations that actual Time is taken into real consideration
Perhaps it will help you to read this: http://en.wikipedia.org/wiki/Time
Slacko says:
May 8, 2011 at 9:46 pm
Forgive me if I’m wrong, but you seem to percieve the trampoline as a representation of the field around the Earth, such that when you envisage a multitude of these you claim they cancel each other out.
I was using it as any example, as the example usually given of this effect of the mass Earth creating gravity by warping spacetime is one of a rubber mat, to explain the diagram above of the warp effect.
So what I was saying is that this distortion at its deepest point, when extrapolated for a 3D figure, creates a continuous boundary layer all the way around, like a shell. So the open side opposite the deepest point of strongest gravity is constrained in some way by this shell – i.e. the distortion is first of all at its deepest point all around, so the effect of actually warping the space is cancelled out – in other words, against what is the Earth distorting in any one direction when it is doing so equally in all directions at the same time? (Assuming for the moment that the “Earth” is like “average” here, a perfectly round sphere.)
There is no distortion. You cannot extrapolate that to 3D reality because the Earth cannot be equally forcing its mass/weight into the space around it at every point to get that effect all around the Earth. It’s simply illogical in our normal everyday 3D reality. You have to show that the Earth is actively forcing its way into this ‘spacetime’ first. If it’s distorting it in one place it cannot be doing so in another.
So, from there I wondered what is does look like if it were ‘equally distorting the space all around it’ and I get the known 3D example of a ball suspended in water. Neither floating nor sinking, just heavy enough to stay in the middle. Now what is interesting in this is that when calculating about such things the force of the water acting on the body is taken into account. This is also missing from the spacetime scenario, at least I haven’t seen anything about it, spacetime appears to be something that can be distorted but not something that has any reality of its own which any medium should have…
Simply taking ‘time’ out of the ‘spacetime’, brings us back to normal reality where things do act on other things, relative to other things.
From there, from the Earth being suspended in some medium, called space, I wondered how gravity was actually working on all these points of distortion of the space around it, which includes how space is forcing its presence onto the Earth as water is doing on a ball suspended in a bath of it, for example, the pressure is equal on all sides. That boundary layer between surfaces, between the surface of the Earth and the edge of space all around it. (The edge being the rubber sheet or the trampoline, both the rubber and trampoline extend in all directions from their edges.)
Thinking of boundaries, I thought then of the boundaries around a moving object in space, such as the golf ball example I gave. It’s a good example, because these boundary layers of an object travelling in space are very well understood, wind tunnel testing and so on. So a golf ball can also have spin, like a tennis ball hit hard and sliced, and how these effect the air they are in are well known. The Earth is exactly like this in the space it is in, travelling fast like the golf ball it will have the same kind of boundary layers around it made out of whatever constitutes the space around Earth.
Immediately around the speeding golf ball all is quite, the Air (Air is a gas; liquids and gases are fluids, in contrast to solids) is still immediately around the golf ball, sticking to it, then comes a boundary layer of slurpy moving Air which as it passes over the golf ball begins whirling and tumbling behind it, above that boundary layer the Air is travelling at great speed past the ball. What happens when spin is added?
So far, an Earth merely with presence in this honey space fluid around it would behave as a ball in a bath (assuming for the moment a closed universe with edges, let’s say it itself is a bubble of Space in some other fluid and all our billions years history are in that bubble and the bath representing that bubble which is our universe), wouldn’t be doing very much at all, suspended as it is in this and we haven’t felt it, not that I know of, bumping into the edge of our universe bubble. So we would have it suspended somewhere in this Space Fluid or bumping into the edges and the Space Fluid exerting its own pressure on it and not a lot happening, except for the fact that it is moving at great speed through it.
Suspended and not moving what is there in its mass that could created gravity, attraction to itself? What happens at the boundary layer of a ball in a bath of water? However, the Earth moving, and spinning is what is said to create the water down the plug hole differences in hemispheres – and thinking of this I wondered if the Earth’s spin is what is attracting stuff to it. Perhaps even pulling in this Space Fluid itself and objects just fall at the speed this happens because they’re in the speed of the Space fluid. Anyway, that’s as far as I’ve got.
I think it is the spin, because if the Earth merely suspended in Space Fluid then it’s not doing anything more than a ball in a bath of water. If only travelling at speed, again, the layer of Space Fluid immediately in contact is still, not a lot happening there to attract stuff to it as ‘gravity’, with the only movement happening in the next boundary layer which is sliding off it and so would be taking stuff past Earth. It must then be the Spin. Earth’s spin is grabbing stuff. That’s what Gravity is. And as its grabbing stuff what it’s really grabbing is the Space Fluid around it and stuff comes in with it.
That it is some kind of fluid medium is the only thing of value from that experiment – and, should be shouted from the rooftops of Science.
Leif – clocks are only one way of measuring time, they do not represent Time. A bat measures time quite differently from us in its hearing, it hears sounds very draaaawn ooouuuttt and sllooowww. It does this even when flying very fast or hanging very still. Perception of time can be different physically as for the bat and for ourselves, is the bat’s clock in this running slow or is ours running fast? But as for the clocks supposedly proving that time in ‘spacetime’ is being warped, they are matter. Matter is affected by gravity and pressure. In our atmosphere which is the gas Air, molecules will travel through it faster the less of it there is, i.e., the higher one goes the less pressure and gravity and so stuff moves more quickly. If it wasn’t for gravity and the resultant air pressure created we wouldn’t hear sounds at all, it takes molecules being constrained by this to give a medium where they are close enough to be moved by sound and to vibrate ‘on the spot’ passing that vibration on. What you, generic, are calling time in ‘spacetime’ and clocks, is only changes in speed.
As someone noted above, ‘they found that the gyroscopes moved a fraction affected by gravity’, and his conclusion, ‘well, duh’.
This experiment isn’t showing any such thing as confirmation of ‘spacetime’, all it’s finding is an extension of our natural world.
But, the Space Fluid is profound, especially as I’ve concluded its capture creates Gravity by the spin of the Earth which explains how bodies of different weights fall at the same speed… Look forward to my Nobel Prix. How much is it worth now?
Or, Earth’s spin plus the immediate still Space Honey around the speeding Earth. Like our Atmosphere pressing down a ton or so per sq foot and we don’t feel it, there could be an intrinsic speed to the pressure of the Space Fluid around the Earth, which would be like then the kind of pressure on a ball from the bath water it is suspended in, on all sides equally. Can we estimate the weight of that still layer of Space Fluid sticking immediately around the Earth from the speed at which things fall in gravity?
Myrrh says:
May 9, 2011 at 4:25 pm
Please do me the courtesy of reading through this thoroughly before responding. I have put significant effort into explaining these things to you, and I’m not going to respond anymore to anything which ignores what I have already explained. Besides, if you stick around to the end, you may find I’ve thrown you a bone or two.
“That doesn’t mean “Time” has slowed down… ..that someone won’t age as fast in space as they would on the ground, do all the molecules in the body slow down in aging? Or just in efficiency?”
Maybe it would help you to consider something more elementary. Time is also affected by relative motion (Special Relativity). There can be no doubt of that effect. It is confirmed every single day in atom smashers at CERN, Fermilab, and other places, and in more mundane applications, such as the Doppler radar images you see on the weather report every night, and the Doppler radar your local police use to patrol your roads. Special Relativity DOES extend all the way down to the quantum world, and explains, among other commonly observed effects, the existence of antimatter. Antimatter, in fact, was “discovered” purely by the mathematics of Special Relativity married to classical quantum theory, years before it was actually observed.
The Doppler shift, by itself, confirms Special Relativity in all its essentials. You may not be aware, but the Doppler shift for sound, which you hear every time a vehicle goes rumbling by, rising in pitch as it approaches, and decreasing as it recedes, takes on very different forms depending on whether you are moving toward or away from the source, or whether the source is moving toward or away from you. Not so, the Doppler shift for light, which takes the same form regardless. Time and space are inherent in the way the formula for the shift is derived for both sound, and for light. Therefore, the ONLY way for that to be so is if both time and distance change due to motion or, equivalently, if light propagates at the same speed regardless of the speed of the observer.
So, we know these things. They have been proven. There can be no argument with this, no wiggle room at all. Special Relativity is fact, and only someone ignorant of the facts would argue otherwise. From that foundation, it is not much of a stretch to conclude that gravity acts to distort time. Indeed, it is absolutely necessary, if inertial and gravitational mass are equal, and exquisitely precise experiments have never measured any difference outside experimental error limits (to understand the difference between inertial and gravitational mass, try google or wikipedia).
“Again, you’re saying things that are still not actually proven, redshifts are still under debate…”
Redshift is a generic term. Generally, we speak of three kinds: Doppler, gravitational, and cosmological. Doppler emerges from relative motion, as I have described above. Doppler redshift is completely proven – enough said. Gravitational redshift is due to electromagnetic radiation passing through a gravitational field. Again, it is not such a tall leap from Doppler redshift to gravitational redshift. It has also been proven by any reasonable standard, by radar signals bounced off of our neighboring planets, among other experiments.
Cosmological redshift is less of a slam dunk. It is, at least, plausible given the other two. And, it fits with our observations. Everywhere we look in the night sky, almost every object is redshifted from where it ought to be. If it is due to Doppler shift, then that means almost everything is moving away from us in particular, and we are effectively at the center of the universe. Given that messiness with Copernicus and Galileo some years ago, which moved us away from the center of Creation, scientists are understandably reluctant to indulge their hubris in reestablishing our existence there. You must admit, barring God himself’s desire for us to be there (and, claiming to know the mind of God is not a little blasphemous), it is exceedingly unlikely that we would be. The only other plausible explanation we have yet conceived is that everything in the universe is moving away from everything else, and this means the entire fabric of the universe is stretching. And, fortuitously or not, it just so happens that the General Theory of Relativity predicts just such a universe is physically realizable. And, so far, it all fits together like the pieces of a jigsaw puzzle. So, either it is right, or it is a series of amazing coincidences piled one on top of another.
So, hopefully to end this discussion for now, I will say to you this: Special Relativity is a fact. Warpage of space and time is a fact. General Relativity is, at the very least, a very good description of gravity which will never be overthrown, just as Newton’s mechanics have never been overthrown, despite what some people appear to believe, but merely extended. Cosmology based on General Relativity is… plausible, and so far, all the evidence appears consistent with it, enough so that there is every reason to continue exploring its implications – I think we may never know for sure unless we find some loophole which allows us to actually reach these far away places and explore them firsthand.
Myrrh says:
May 9, 2011 at 7:11 pm
Leif – clocks are only one way of measuring time, they do not represent Time.
Subjective feeling of what time is does not enter the picture, but experiments show that every person, animal, or thing measures, feels, sees, whatever, time different from any other person, animal, or thing [depending on their relative motion] and every person, animal, thing measures, feels, sees, whatever space different from any other person, animal, thing [depending on their relative motion]. This makes time and space very slippery concepts that are rather useless as measures of reality since everybody’s measure is different. Physicists like to remedy that defect in concepts by combining the slippery space and time into spacetime, and call THAT reality, because everybody will measure, see, feel, whatever, the SAME interval [as it is called] between two events in spacetime and agree to what it is. In this sense we have an objective definition and measure of reality that everybody can agree on.
The rest of your explanation about gas, fluid, etc is I’m sorry to say just junk. Sometimes I think you are close, but then you regress and slide backwards.
But in reality we don’t observe the same time and space agreeing to see space and time in the same way does not make it real (for example calculating a global average temperature that nobody observes).
Bart says:
May 9, 2011 at 7:27 pm
Please do me the courtesy of reading through this thoroughly before responding. I have put significant effort into explaining these things to you, and I’m not going to respond anymore to anything which ignores what I have already explained.
Regardless that you haven’t extended the same courtesy to me? Well, OK, but it is getting tedious that you bring in material without relating it to the specific point I’m making.
Re my: “That doesn’t mean “Time” has slowed down.. ..that someone won’t age as fast in space as they would on the ground, do all the molecules in the body slow down in aging? Or just in efficiency?”
Maybe it would help you to consider something more elementary. Time is also affected by relative motion (Special Relativity). Etc. etc. etc..
And just how does all this “etc.” answer the question I posed? I should be grateful if you’d take the time to digest what I’ve said and with your clearly detailed knowledge of Einstein’s various theories, give me answer to my actual question.
I shan’t ask again because I’m finding it rather tedious to waste so much of my time trying to bring some people’s attention to my actual points, as others are of hearing me do this, and not getting any answers that actually relate to them specifically as actually asked. I’ve of course heard that scientists are absent minded, but I thought this was because they were so well able to direct their concentrations on specific problems, here it appears the converse…
However, having looked up some on Special Relativity, in response to your post, I see it is something I would like to explore more, to think about. But not in any detail here, because it is actually irrelevant to the subject I’m trying to discuss which is General Relativity, as the subject of the thread. But, if you can come up with an answer to my question, as above in this post, re it, please do; I’d be interested to hear it and shall add it to the information I’ll take with me when I do have the time to explore it further.
Leif says:
May 9, 2011 at 7:42 pm
Re my: “clocks are only one way of measuring time, they do not represent Time.”
Subjective feeling of what time is does not enter the picture, but experiments show that..
As above in my reply to Bart, I do think this subject is fascinating, and would love to discuss it further when I have the time, but,
The rest of your explanation about gas, fluid, etc is I’m sorry to say just junk. Sometimes I think you are close, but then you regress and slide backwards.
Well, that’s Myrrh’s Theory of Gravity, as I outlined above. I say it has an excellent chance of being proved correct because the states of matter of solid, liquids and gases are so very very well known to applied Scientists who for example actually understand what is happening around a speeding golf ball in the fluid Air around it, of what is happening in the border when two surfaces meet such as a ball in a bath of water and so on, can calculate such stuff.
As I said, there is nothing in the descriptions of General Relativity that include ‘time’, it is merely an unproven assumption that there is such a thing being warped, and nothing in the descriptions of the method the Earth is supposedly warping this that can be successfully extrapolated into 3D reality as it stands; the descriptions are all of Space being warped. And, there is nothing in the descriptions by the scientists who have conducted and analysed the experiments of Gravity Probe B to suggest they have even come close to proving General Relativity, on the other hand, they fully confirm only that the Earth is in a Fluid which it moves around.
What more do you want for basic confirmation that my premise that this is no more or less a problem than that of a body with mass moving in a fluid, such as the golf ball in Air?
I have confirmation that my premise to my theory is real. There is no confirmation forthcoming that General Relativity’s premise is real.
As Einstein said – “The ether of the general theory of relativity is a medium which is itself devoid of all mechanical and kinematic qualities, but helps to determine mechanical (and electromagnetic) events.”
http://www.tu-harburg.de/rzt/rzt/it/Ether.html
And that’s the problem, why it doesn’t make sense and no confirmation has yet been found to show it is real (as several others have noted, the Gravity B probe has had to torture the data to make its claims) because it doesn’t take into account that the Ether is an entity in its own right, another form of matter perhaps, but certainly which has been shown to be a Fluid in the common science understanding of Fluids, therefore, it should act as do other fluids around bodies, exerting pressure, clinging to bodies in flight etc., just as do fluids like gases and liquids.
What is junk and simply illogical, is Einstein’s assertion that this Ether Honey is itself devoid of natural qualities as all other matter. But somehow, miraculously, it acts upon matter without physical means. [Einstein’s Ether is his God, no? ]
So, to the experiments and general extrapolations from known natural science towards proving Myrrh’s Theory. [that, from one or more in combination, of pressure of the Fluid Space Ether on the Earth if in closed environment such as ball suspended in water in a bath where the pressure of water is acting equally on all sides of the ball; this amount of Fluid Space clinging in stillness beneath the boundary layer of slurpy Fluid Space tumbling past it such as when the golf ball is hit at speed through the less dense fluid of the gas Air; the spin of the Earth which is creating a vortex extending into the fluid space pulling stuff in. Which is Gravity. So, gravity is this space stuff at the speed which this pressure of fluid space exerts on the Earth or the speed it is being pulled in by the spin of the Earth or both, and which varies depending on the mass/conditions of the different bodies; and so falling bodies only under gravity, which is the definition of freefall, fall at exactly the same speed because within this and so travelling at the same speed as the fluid space meeting Earth.] Extrapolated from ball in bathtub, what would be the weight of the pressure being exerted on the Earth by Honey Space Ether to force itself at the speed of gravity we feel on Earth? Ditto the layer of still fluid space sticking to Earth in flight through it as the golf ball, and what would have to be the strength of the spin to pull in this fluid to achieve the rate of gravity on Earth? Since we know, well some do, the rate at which the Earth spins creating the Coriolis effect, is it possible to work out more details of the qualities of the Space Fluid? How much ‘finer’ it is than fluids like gas and liquids, air and water? And amount of it? Does this relate to the missing dark matter, i.e., is it dark matter?
An interesting post from a seaman in a discussion about the vortex created by the spin of the Earth in the different directions water goes down a plug hole in opposite hemispheres (this must also be relevant to the way Air of our atmosphere is moved around in the different hemispheres, that wind (Air on the move) stays in circulation according the hemisphere it is in, i.e. Wind circulations do not cross hemispheres, there is some mixing at the equator, but otherwise the circulation is confined to the hemisphere the gas Air is in.)
http://www.guardian.co.uk/notesandqueries/query/0,5753,-20326,00.html
So, gravity then like water and air, depending on the spin of the Earth, would be in free fall at the equator??
Anyway Leif, I say that General Relativity’s premise is what is Junk here, which is why there has been no success at all in proving it and the claim that Gravity B has somehow proved something of it doesn’t bear close scrutiny. The objections others have made here in this regard re methodogy and interpretation and so on are pertinent. Anyone here with the necessary skills to look at Myrrh’s Theory..? Or combined skills?
Myrrh says:
May 10, 2011 at 4:14 am
Well, that’s Myrrh’s Theory of Gravity
So you finally came out of the closet. Experience shows that confronted with believers of such caliber, no attempt of further education is possible.
? Leif, what do you mean? I’ve explained here that I’ve only just, in this very discussion, worked it out. I’ve never thought about it before.
Now, what was Einstein saying about time….?
Myrrh says:
May 10, 2011 at 4:14 am
“As I said, there is nothing in the descriptions of General Relativity that include ‘time’… the descriptions are all of Space being warped.”
Ah… that’d be no. The metric of General Relativity is specifically formulated to produce an interval of “proper time”, and relate it to “coordinate time” and space.
Myrrh, you just do not understand enough about the subject even to know what to criticize, and seemingly have no wish to learn. Instead, you insist on playing the role of a quixotic warrior, assaulting the most heavily fortified sections of the castle with a garden hoe, dreaming of rescuing the fair Dulcinea del Toboso imprisoned within. I do not see any point in continuing to play a part in this fantasy.
Astronomy Picture of the Day: May 10, 2011
Gravity Probe B Confirms the Existence of Gravitomagnetism
http://apod.nasa.gov/apod/ap110510.html
The diagram notes:
Frame Dragging Precession = 39 milliarcsec/year
Geodetic Precession = 6606 milliarcsec/year
neither is given an uncertinty measurement.
lunisolar precession = 50287.2 +/- 0.5 milliarcsec/yr.
http://www.astro.spbu.ru/astro/publications/tsvetkov/tsv-precppm.pdf
(this paper supports a correction of -3.8 +/- 0.5 milliarcsec/yr to the IAU 1976 value of 50290.966 milliarcsec/yr.
lunisolar precession is the observed astronomic precession, which must include the Geodetic and Frame drag(?) effect. The uncertainty in the lunisolar precession is less than the frame dragging amount.
The difference between de Sitter precession [Geodetic] and Lense–Thirring precession (frame dragging) is that the de Sitter effect is due simply to the presence of a central mass, whereas Lense–Thirring precession is due to the rotation of the central mass. http://en.wikipedia.org/wiki/Geodetic_effect
The [Earth] Precession (axial rotation) was later explained by Newtonian physics. Being an oblate spheroid, the Earth has a nonspherical shape, bulging outward at the equator. The gravitational tidal forces of the Moon and Sun apply torque as they attempt to pull the equatorial bulge into the plane of the ecliptic. The portion of the precession due to the combined action of the Sun and the Moon is called lunisolar precession. Which amounts to 49,900 (+/- 200)milliarcsec/yr. http://en.wikipedia.org/wiki/Precession#Astronomy
don penman says:
May 9, 2011 at 11:00 pm
“…for example calculating a global average temperature that nobody observes.”
The problem with that is that it actually has limited physical meaning, as temperature is an intensive property. That is why Pielke, Sr. is so adamant that the proper metric for climate change is the extensive measure of ocean heat energy.
Re: Stephen Rasey says: May 5, 2011 at 8:48 am
Ring Laser Gyro around Earth’s equator.
If a Frame Drag effect for Earth is on the order of
39 milliarcsec/year, and
the time for a light pulse to circle the earth in a ring laser gyro fiber
(assuming index of refrac about 1.62 = 200,000 km/sec as speed of light,
Circumference of 40,000 km) = 0.2 seconds.
Then the frame drag in the time for the light to make it’s loop is
7.6 E-09 meters at the surface of the earth.
which is about 0.02 wavelengths of visible light,
and the time for the light pulse to span that distance is:
3.8 E-17 sec.
Myrrh says:
May 10, 2011 at 9:45 am
I’ve explained here that I’ve only just, in this very discussion, worked it out. I’ve never thought about it before.
Well, you got it wrong. But, I don’t think you came completely blank into this very discussion. If you did, then the seeds we try to sow fell on completely barren ground.
You can think what you like Leif, I’ve explained how I came into this and that it was my first opportunity to actually question people about it. But you’re right, I didn’t come into this “completely blank”, I came with enough intelligence to use the internet for my own searches specifically here as I’ve used it to explore the properties of gases etc. when I wanted to understand why AGW said a heavier than air molecule could stay up in the atmosphere accumulating etc., from which I learned about heat capacities and ideal gas laws and so much more.
Bart – re your last post to me: /#comment-657331
As I said earlier to Leif, it doesn’t matter what you call it, the Space that is supposedly being warped, or what you decide to attribute as its properties which I realise is so heavily ingrained in the ‘spacetime’ idea that it becomes difficult for some to separate that out from the mechanics of the ‘concept of the warping’.
The mechanics of the concept of warping are as described in the diagram, and stated ad infinitum by those teaching General Relativity. It is simply describing a 3D body warping the 3D space around it. The diagram is a two dimensional representation of a three dimensional scenario. There is no time element involved in the mechanics of the concept, only body plus space around it.
The 2D description cannot be extrapolated out the 3D in real space of a space which is an entity in its own right and so not only can be affected by other matter but also can affect other matter. The Gravity B probe has proved one great thing, it is a real something, described as a fluid, like honey, which is being moved about. It is therefore not the ether or space or spacetime of Einstein’s which quote I gave above, which he says has ‘no mechanical or kinematic properties but helps in determining mechanical events’ which is simply an assumption that such a static entity exists, and simply also ridiculous in the light of his use of it by saying it can be warped – if it can be warped, it can be moving, and if it’s moving it has kinetic energy. Gravity B has shown that it is moving.
[And this, Leif, is my method, I come across something relevant and explore it, to remind myself what these terms mean and further my own understanding, as I’ve just done now by making a search on kinetic and mechanical to remind myself so able to add the elaboration on my theme I’ve just written to Bart.]
http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=0030nq
See section III Longer Science Explanation
So Bart, re your comment about my state of knowledge, or rather lack of it, in this subject. I think it has been to my advantage here. I have managed to explore this which was puzzling to me because it was never explained in the times I’ve seen it demonstrated when I couldn’t get answers to my own questions about it, the guy on the other side of the TV screen couldn’t hear me.., in a discussion which I joined in because others too saw the same disjunct I did and a discussion full of interesting observations from all posters here about the experiment itself as well as the subject generally which is very much appreciated, even from those I’ve disagreed with. I’ve enjoyed it, particularly so because I’ve sorted out in my own mind how gravity could work in light of the known science about matter in normal 3D reality and I no longer have to shout at the TV screen. Whether I’m right or not it’s been an interesting journey. So, good bye and thanks for all the fish.
“So, good bye and thanks for all the fish.”
I fear it was nothing but a gnab gib.
What has a beginning …
Sadly Bart I shall have to leave discussing Einstein’s light which on first thoughts during this discussion it seems to me could be could be confusing perception with absolutes and I have no problem with SR if it’s a measure to ‘standard’ i.e. our human, perception, but I have a prior engagement with the water cycle (and carbon dioxide in the atmosphere in case you extrapolate a nuance too far…). My initial search, during this discussion and this morning, turned up these pages, on the basics and on recent research :
http://abyss.uoregon.edu/~js/ast122/lectures/lec20.html
http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html
http://www.newscientist.com/article/dn6092-speed-of-light-may-have-changed-recently.html
And just now, a page including the various theories kicking around, http://www.speed-light.info.index.html
Oh heck, when something grabs my attention…
Paradox Resolved:
http://www.enterprisemission.com/speedlight.html
Enjoy!
Myrrh says:
May 11, 2011 at 2:29 am
Oh heck, when something grabs my attention…
Paradox Resolved
The ‘paradox’ was due to the effect of thermal radiation [from the nuclear reactor on board] and the force it can bring to bear on a surface. Radiation facing outwards, for example, radiates directly into space with an effect that cancels out. But radiation emitted toward the center of the spacecraft is reflected by the high-gain antenna and the main equipment compartment. See http://www.centauri-dreams.org/?p=17427
Possibly so. There’s an awful lot on variability of constants, isn’t there?
On the fine structure constant
http://www.sciencedaily.com/releases/2006/06/060609122206.htm
http://www.sciencedaily.com/releases/2007/04/070402153241.htm
I rather like the comment Moffat from a 1999 paper “It is easier for me to question Einstein’s theory than it is to assume there is some kind of strange, exotic matter around me in my kitchen.” http://www.sciencedaily.com/releases/1999/10/991005114024.htm
Myrrh says:
May 11, 2011 at 8:08 am
Possibly so. There’s an awful lot on variability of constants, isn’t there?
It is important that we all the time investigate these things and everybody wants to prove Einstein wrong. To date, no such variations have been established and no-one has proven Einstein wrong. But the search goes on, as it should.
Myrrh – this is what I mean by “you just do not understand enough about the subject even to know what to criticize.” Were the speed of light to change, and there is no remotely compelling evidence yet that it ever has, if reference frames do not transform according to the Galilean Transformation, then there is warping of time and space involved. And, the departure from Galilean rules is always observable at sufficiently high relative speed (where the signal to noise ratio allows us to see it).
You keep overgeneralizing, picking out any minor unresolved issue (even if it is more than a decade old, and you are unaware of the resolution since) as “proof” that the entire concept is wrong, even when the unresolved issue itself requires subtraction of all the other larger effects predicted by the theory to see.
This is no house of cards you are assaulting, it is a massive work of stone – not impregnable, but assuredly permanent. You are not going to gain entry, much less bring it to collapse, by chipping a few shards of rock from the foundation, even if that is, indeed, where the pebbles you put on display came from.
On the issues of dark energy and dark matter: I found it pretty hokey the first time I heard of it, too. But, then I started reading about it. It is no flippant, notional WAG. The subtle thought which has gone into developing the concepts is a tour de force of human reasoning and logic. Which is not to say that it is correct, just that it cannot be flippantly dismissed, and the plans to search for its signature are solidly grounded.
And, if that signature is not found, does that mean the entire edifice of GR will crumble? Hardly. An analogous situation would be the building of a skyscraper – we have reached 3000 feet of solid concrete and steel, but the latest additions wandered off the CG and they are leaning. Do we tear down the entire tower and start building anew? Or, do we simply rebalance the upper stories, and continue building upward?
From Nature today:
http://www.nature.com/news/2011/110511/full/473131a.html?WT.ec_id=NATURE-20110512
“The project was soon beset by problems and disappointment when an unexpected wobble in the gyroscopes changed their orientation and interfered with the data. It took years for a team of scientists to sift through the muddy data and salvage the information they needed.”
I read a fair amount of the discussions between Bart, Myhrr and Svalgaard because I am attracted to the passion that ignites such sparks in a discussion and so I may have missed someone else commenting on the mission’s “problems”. I’m suspicious of such mathematical corrections to a problem with the main instrument on board in such a delicate test. It could be that rather than admit that the mission was a mechanical failure they mathematically rationalized out the results – after all it was decades in development and was expensive – “we gotta do something”.
Unfortunately, though, when you are testing such a fundamental theory, it seems to me you would have to assume the theory is correct to make the adjustment calculations to your satisfaction, otherwise how can you say that you have tested the theory and found it correct. Isn’t it also possible that the wobble developed in the gryroscope was a manifestation of a real effect caused by the real factors defining something different than Einstein’s gravitational theory. One could prove the Titanic unsinkable by mathematically moving everything out of the ships way until it went to the scrap yard. Sorry guys, we got to do this over again just to see if we end up with the same wobble.
Gary Pearse says:
May 11, 2011 at 10:42 am
we got to do this over again just to see if we end up with the same wobble.</i<
Has already been done: From Nature today:
http://www.nature.com/news/2011/110511/full/473131a.html?WT.ec_id=NATURE-20110512
Gary Pearse says:
May 11, 2011 at 10:42 am
“Sorry guys, we got to do this over again just to see if we end up with the same wobble.”
True enough, Gary. It is difficult to argue that this particular experiment does more than prove that the data do not flatly contradict the theory. However, as Leif’s Nature article discusses, there have been other tests of the precession and frame dragging effects, and there will be at least one additional test soon. Furthermore, other tests of other aspects of GR all tend to confirm it as a whole. Regarding this point, you may think of it as a function for which we have several data points, and we are interpolating the function between the data points with GR. It would be truly astounding if there were a sudden discrepancy between reality and the smoothly interpolated curve.
“Isn’t it also possible that the wobble developed in the gryroscope was a manifestation of a real effect caused by the real factors defining something different than Einstein’s gravitational theory.”
It’s possible, but not very likely. They are trying to measure such a tiny signal, and random and unrelated effects due to imperfections in the instrument make it very difficult to see that signal in the first place.
“…I am attracted to the passion that ignites such sparks in a discussion…”
We learn by doing, and I find nothing helps me understand concepts better than having to explain them to someone else. Which is why I often find myself explaining my researches to my wife who, bless her heart, has a difficult time with fractions. If I can make her understand it, then I know I understand it.
“If you can’t explain it simply, you don’t understand it well enough.”
– Albert Einstein
Bart says:
May11, 2011 at 9:30 am
Myrrh – this is what I mean by “you just do not understand enough about the subject even to know what to criticize.”
Bart, give me a break from your patronising, will you?
We each have various skills and talents, mine is spotting nonsense…
How about attempting to answer my question about aging in space?
I realise I’m treading on toes here, of those for whom Einstein is some kind of hero, but until you can show that his idea of ‘space-time’ in General Relativity has any actual real credibility as a concept then all the ‘proofs’ that you keep churning out are still merely 3D effects. When I ask ‘where is time in the GR diagram?’, you come back with the repeated strange idea that mass bends time, but it’s nowhere to be found on the diagram. All we see is bog standard three dimensional space which is being warped. And then you give me ‘proof’ that light bends around planets and again this comes with the unsubstantiated ‘and time’, when it was already part of the thinking in 3D space. Einstein’s ‘warping time’ is an illusion.
Back to Gravity B in opening post – “if gravity did not affect space and time” – where is time being affected?
What did they find? Only that normal 3D space was affected.
How does the gyroscopes being affected by gravity prove that the Earth is warping time? How does a spinning Earth pulling space around it, no different as I’ve shown in normal science understanding of bodies in motions in fluids, prove that Earth is warping Time?
What’s wrong with this experiment is that they’re proving nothing at all about what they claim to be proving. Nothing that 3D science doesn’t already explain or can’t extrapolate to. They’re merely confirming normal 3D science knowledge.
I’m sorry, I’m really not impressed.
Anyway, I thought I’d take a look at the Mercury example you bring attention to as proof of Einstein’s GR. Now, I know that many ancient civilisations kept meticulous records of planetary movements and observed phenomena, the Chinese liked tracking comets, the India Vedas which go back 10,000 years have many descriptions of events in their history together with what was happening in the skies at the time, so can be accurately dated now with our computerised ability to backtrack, and so on. But, the first thing I found was again the wiki page on beginning history of the previous centuries to Einstein, and I thought I should take a closer look at that first.
http://en.wikipedia.org/wiki/Tests_of_general_relativity
Scroll down to “Perihelion precession of Mercury”
It appears that Einstein’s 43″ has now been superceded by more accurate measurements, 56″, his now being only a part of the mix.
The next section: “Deflection of light by the Sun”, gives some background history, that “Henry Cavendish in 1784 and Johann Georg von Soldner in 1801 had pointed out that Newtonian gravity predicts that starlight will bend around a massive object. The same value as Soldner’s was calculated by Einstein in 1911 based on the equivalence principle alone. However, Einstein noted in 1915 in the process of completing general relativity, that his (and thus Soldner’s) 1911-result is on half of the correct value. Einstein became the first to calculate the correct value for light bending.”
It was because of this, because confirmed by Eddington, that Einstein’s theory of gravity became famous and when asked what his reaction would have been if his general relativity had not been confirmed by Eddington, he quipped – “Then I would feel sorry for the dear lord, the theory is correct anyway.”
So, next step. I looked up to find Soldner’s connection in all of this, since Einstein initially agreed with him.
And I found this: http://www.scribd.com/doc/30416020/Johann-Georg-Van-Soldner-1801-light-bending-historical-mistake-and-Einstein-s-time-travel-stupidy
Intrigued, how could I resist? So what do you make of it?
I’ll tell you what I think possible. I think that Einstein spotted Soldner’s maths error and corrected the error, which if Soldner has spotted it would have ‘doubled’ to the now famous Einstein’s ‘proof of his warped time theory of gravity’. Simply by attaching, superimposing, his strange SR light travelling perception and time bending masses in a kinetic and mechanical 3D ether while claiming it wasn’t kinetic and mechanical, and everyone fell for it. Because, wow, what a concept!
Grin.
Possibly. So I investigated further. http://www.wbabin.net/eeuro/vankov.pdf
Seems Einstein corrected his work so many times never again referring to the original which Schwarzshild said had such a surprising result having come out of his fantasy land explanation.
Do read 2.1 Comments 2.1.1. Historical remarks.
It’s very funny. Einstein’s correcting as he goes, or as others have calculated perhaps, continues to maintain that he’s saying the same thing. Does so remind me of AGW arguments from the warmists, who are similarly adept at claiming they were always saying that warming means it will get colder..
..you of course Bart, will be able to follow the maths, me, I just pick out that no one has as yet satisfactorily shown that mass warps time and if the mess of arguments about it at Einstein’s time are anything to go by as Vankov tells it, no one not even Einstein himself understood what he was saying.
No wonder none of you can explain how “time” gets warped by bodies, and all your experiments can be explained in 3D space, and why all the ‘equations work’, all fits in. As in the Gravity B, you squash whatever results you get into Einstein’s time, which is purely imaginary, and refuse to see it’s saying nothing at all about it.
What a genius.
Here’s another example of how not impressed I am, as with the Gravity B gush, http://www.einstein-online.info/elementary/gravWav
“With space and time not as a rigid background structures, but as dynamical objects (changing as the world changes in and around them), general relativity predicts fundamentally new phenomena. One of the most fascinating is the existence of gravitational waves: small distortions of space-time geometry which propagate through space as waves!”
And goes on to compare it with sound waves. How can you not see this is our normal 3D reality with Space still fully part of it in its physics? The only people who can be amazed by such “fundamentally new phenomena” are those who’ve never known or have rejected that finer and finer manifestations of energy are our 3D reality, who think perhaps that space is empty or a vacuum and so are unduly excited by such a claim.
Certainly one thing, Einstein’s description of his ether is at total odds with the claimed effects he gives such as gravitational waves which can only come from an ether with mechanical and kinetic energy.
Bart and Leif, and anyone else interested, this paper claims it gets Einstein’s result from Maxwell, i.e. without any need to invoke GR. http://www.mrelativity.net/Papers/14/tdm13.pdf
What I see is that warping time can’t be shown; that all these so called proofs of GR are still 3D space calculations from known work of the day and with fudging to date to claim GR responsible; that it upsets a lot of people when this is pointed out.
And for the last, scientists are no more objective than the rest of us when it comes to emotional attachments being criticised.
Anthony – you invite people to post on this site anonymously and then say if they want respect they should ‘come out from behind the curtain’, whatever that means for you. It is you who show, by tedious repetition of this, lack of respect to the posters here when you castigate someone for posting anonymously. So now it’s confirmed for me too, as I’ve seen you do so often, and have cringed every time, you have no respect for the majority of your posters. If you want to know everyone’s name, then set up a blog where it is required. Or stop whinging.
Myrrh says:
May 11, 2011 at 4:41 pm
“How about attempting to answer my question about aging in space?”
Which question was that? Whatever it is, it is a confirmed fact that normal, natural processes which contribute to aging are less rapid in space compared to similar processes unfolding on the surface of the Earth. The Space environment, however, takes its own toll on the body, and the difference in rate of time is quite small, so it’s not a very effective time machine into the future.
“When I ask ‘where is time in the GR diagram?’, you come back with the repeated strange idea that mass bends time, but it’s nowhere to be found on the diagram.”
I have explained that to you repeatedly. The diagram is an analogy. It is not to be taken literally as describing the warping of space and time. I don’t know why you can’t get past this.
“How does the gyroscopes being affected by gravity prove that the Earth is warping time?”
It doesn’t. But, if it gave an answer outside reasonable error bounds from that of GR, and the difference between measured and expected performance were repeatable in other experiments, GR would require modifications. As it is, the geodetic precession result was confirmed to high accuracy. The frame dragging effect has been confirmed to lesser accuracy, and will be measured again in the near future.
“It appears that Einstein’s 43″ has now been superceded by more accurate measurements, 56″, his now being only a part of the mix.”
You appear to be looking at the wrong line. Look for the line where it says: 42.98 ±0.04.
“And I found this:”
At a glance, I saw a guy using a closed form elliptical orbit solution to describe the bending of light. Fail. The guy threw some random equations around until he came up with a formula that agreed with his already determined solution. You should be very careful of accepting just anything, just because it is written down somewhere. There are a lot of crackpots on the web.
“I think that Einstein spotted Soldner’s maths error and corrected the error…”
Incorrect. The classical formula simply does not give the right answer. This ground has been picked over for nearly a century. People who desperately wanted to discredit Einstein gave it their best shot, and failed. Because, the formula is right, and has been verified over and over again.
“Bart and Leif, and anyone else interested, this paper claims it gets Einstein’s result from Maxwell, i.e. without any need to invoke GR.”
There are many ways to formulate the problem. If you consult the Relativity Bible, you will find in Box 17.2 “Six Routes” to “Einstein’s Field Equation”. Number one is “Model geometrodynamics after electrodynamics…” Properly done, it leads back to the same spot. All roads lead to Einstein.
One last…
“Does so remind me of AGW arguments from the warmists…”
It is nothing like the AGW debate. The scientific establishment of the day was virulently against Einstein. Later, the Nazis and the Soviets, in particular, were keen to discredit him. That Einstein never even received a Nobel Prize for either Special Relativity or General Relativity should tell you something of the resistance he encountered.
He won the day because, in the end, he was right. Again, and again, and again, experiments confirmed the correctness of formulas derived from his theories. The establishment could only hold out so long before it had to give in.
AGW, on the other hand, has been accepted and promoted by the Establishment from early on, much like the theories of now discredited hacks in totalitarian countries who tried to take Einstein down. It has been around a relatively short time, and has passed no tests.
Great to see some more common sense and straight talking from Miles Mathis.
“At a glance, I saw a guy using a closed form elliptical orbit solution to describe the bending of light. “
I was hasty – the orbit equation isn’t necessarily elliptical – you forget these things when you don’t use them every day, and I haven’t bothered with hyperbolic orbits in ages. If it were, though, that would be the least of the problems with that very silly web page.
There is no closed form solution for radius as a function of time, and it does not have a semigroup property. The true anomaly (theta) is itself a function of time, and must be differentiated, too. And, so on. The page is essentially a mathematical word salad. As I said, there are a lot of crackpots on the web.
Malaga View says:
May 12, 2011 at 12:30 am
“That is horrible science, no matter how you look at it..”
It is a horrible commentary. The guy clearly knows little about the experiment beyond his preconceived notions.
Bart – will have to leave replying to you until later this weekend or beginning next. I’ve been rather shocked by what I’ve been finding and don’t have time to concentrate on it just now. Not to leave you on tenterhooks, it’s about the accusations made at the time that Einstein plagiarised the work of others.
Meanwhile enjoy: http://www-pw.physics.uiowa.edu/space-audio/sun-rings/Kronos-Lecture/gurnett2.mpg
“Not to leave you on tenterhooks…”
The anticipation is killing me…
“…it’s about the accusations made at the time that Einstein plagiarised the work of others…”
Wouldn’t that be completely moot at this point? What does it have to do with whether the theory is right or not?
“…will have to leave replying to you until later…”
I doubt I’ll be looking back. I really have no interest in any more pseudo-physics or phony muckraking websites. Hopefully, I have imparted some useful and convincing information to you and others reading along.
OK Bart, I just checked back to see if you replied. So you know all about the details of Einstein’s plagiarism? Though clearly you haven’t noticed or ignore that these go back to the original sources who were not publishing from any kind of racist angle. This is what disheartened me, having to go into that world, but, thinking about it yesterday I was struck by the fact that often the pertinent facts to the truth of something are kept in record when no longer in general consciousness by the energy of those who are angry/hate for one reason or another, regardless of the reason. Like this site for example, it’s existence as it has developed is fuelled by the anger/hate at the manipulations of science by world powers and corrupt co-operation of scientists, and all with layers of manipulation by vested interests according to ideology. Doesn’t make the information exchanged here as to the truth in the origins and reach of AGW tentacles a lie. That’s the warmists accusation against this site.
Anyway, it is still known, that, for examples, what Newton said about matter and energy, that experiments were already being done before the turn of the beginning of the last century showing and utilising e=mc2, that the equation so expressed was being used and published by the Italian Olinto De Pretto for several years previous to Einstein claiming his amazing ‘intellectual revelation out of nowhere’, Einstein spent time in Italy and could read Italian. None of which background he credited, he couldn’t, because he came up with nothing new from his own thinking building on concepts which had existed previous to him or being published from long work around him, he simply took them. And he really didn’t understand what he had taken, that’s why he kept producing and endorsing garbled statements about it all and getting caught up in his own lies about what he had or not read previous to his appearance as the new brilliant science genius of the age.
I’m just so disappointed. I was amused to find it possible that he had spotted a mistake and turned it to his advantage, because I thought he was a genuine scientist and this was a lapse all too human nature couldn’t then admit to after all the lauding and praise, but it’s far murkier than that and so no longer funny.
So too complicated for my time constraints to go into to rebut the rebuttals, it’s for Science itself to clean out its own stable and work out how far that has set back general scientific knowledge by taking it into fantasy land of a blank vacuum Space/Time around us which can be warped but has no mechanical or kinetic energy yet somehow miraculously influences us and creates gravity.. With the state of Science as we see it now in the Global Warming scam, there may not be enough number left in any discipline who care to give credit where it is due.
So point taken, this has nothing to do with the whether the theory is right or not.
Back to General Relativity. It has not been proven and physically can’t be, as in the sentence in last para, it’s base premise is utterly stupid so not surprisingly its method to show its workings is equally, though now it has grown like topsy to even more absurdly, so.
I doubt I’ll be looking back. I really have no interest in any more pseudo-physics or phony muckraking websites. Hopefully, I have imparted some useful and convincing information to you and others reading along.
Whether or not you come back to read this reply, I can only speak for myself here, but you have not provided any convincing information to me.
When you can show how a mass like Earth can bend space/time all around it to create gravity as depicted, I’ll be convinced.
Until then it stands nonsense. From its base premise of Einstein’s aether it will take more than using common or garden real 3D science, as has this Gravity B project, to fudge that you can’t supply any information on it, let alone convincing.
The very description of it claiming 3D science is absurd, a body cannot exert pressure in all directions simultaneously without it expending a great deal of energy doing so, or any one movement of warping as a heavy ball on a rubber mat will cancel out if the effect could be in every direction, remaining as a entity in that space as in suspension and which means the greater energy being from its surroundings acting on it, not it acting on its surroundings. The Earth is expanding like a balloon is it, creating gravity all around it? We hadn’t noticed.
To not be able to think through to the 3D representation of this 2D diagram in our physical universe is a drawback, I would think, for a scientist in this field. And, ‘explanations’, which are no more than constant repetition of the claim, based on an unproven theory about a physical concept of the space around us unknown in example to science in the real 3D world, shouldn’t convince any scientist.
I’d found this yesterday which I thought you might appreciate better than my maths language free explanations, through exploration here into the concepts (before I got disheartened by the foray into Einstein’s history): http://scienc1.wordpress.com/2008/10/27/mercurys-perihelion-and-einsteins-general-relativity/
I couldn’t follow the maths, but was interested to see that he was saying that all the explanations from Einstein’s 4th Dimension people are unable to provide a 4D maths to go with it. Which is why I now suppose they keep screwing with the 3D as in this discussion re Gravity B claiming 3D effects prove it, I loved the duh, and particularly in your and Leif’s comments, by claiming it ‘is an analogy’ relating to some higher level of learning that I’m incapable of understanding because I’m obviously too uneducated in the finer points, if not downright thick..
..and yet I keep finding that the most basic science questions I pose of some who call themselves experts here go unanswered, either by misdirection or ad hominem the usual response upon asking for clarification. Still can’t find any proof let alone explanation that blue light from the Sun heats the water in our oceans, not anywhere on any science pages I’ve looked through, and I’ve looked and looked, (sigh), it must be out there somewhere.
Oops, link missing energy – http://science1.wordpress.com/2008/10/27/mercurys-perihelion-and-einsteins-general-relativity/
Since it came up in the accusation of ‘racist’ sites promoting anti-Einstein information.
On looking for who else had Jon Bjerknes’s book I found the Armenians had it. I know about the Armenian massacre by the Turks and I’d no reason, I hadn’t explored further, to think it wasn’t the particular Muslim faction anti Christians who then used the standard Sharia law applicable to those of dhimmi status, of death to those who objected to their rule, when the Armenians appealed for help to the British. I’m not directly putting up what I learned, but more detail about this history can be found on some links here: http://hayq.blogspot.com/2007/09/blog-post_7815.html
I think most of us ‘skeptics’ about AGW have been shocked to discover the ideology driving some to promote it, this has nothing to do with ‘racism’, but like all such ideas, from an aberration in human character which is by default co-operative in nature. And therein lies its strength in changing human history for the worse, in co-opting that nature of some by the few easily turned to ‘permission’ to create an immense amount of heartache for the many. Reasons to justify such the only thing that differentiates one movement from another through our world’s long history.
For myself, whenever I step into these worlds past or present I first recall what someone said who had survived existence under Lenin and Stalin and being starved and abused as slave labour in Hitler’s camps. After recounting the history in Germany and being told the listener hated the Germans for what they had done, said: “There are good and bad in every nation”, and continued with stories of her own nations’s atrocities to others. It helps me to retain balance whenever I find as I’ve done in exploring AGW, that there a people in the world with power and no sense of worth of the other whatever the names of the ideologies which they use as excuses to bolster their lack of self-worth. Doesn’t mean we have to be like them in trying to stop what they’re doing.
Finally. Re speed of light. One of the things that has puzzled me in the discussions on Solar energy heating the Earth in the AGW arguments is the emphasis placed on the ‘highly energetic’ photons of Visible light from the Sun, as if that automatically means that they are therefore more capable of ‘doing stuff’, because, it takes a lot of heat to produce these and it seems to me then that the real ‘high energy’ is in the heat, and so like in an ordinary light bulb where 95% of the energy is given off as Heat energy to the 5% Light energy, it would follow that the high energy capability of doing stuff is still with the heat, (therefore, in the AGW arguments, the Thermal IR given off by the Sun radiating to Earth and not the Visible light radiation). I decided that this was a confusion between ‘highly energetic’ and ‘high energy’, the former merely means that it is moving faster in the same length of space, not that it is more powerful as a ‘force’.
The Visible light from the Sun, especially the shorter more energetic wavelengths of blue light, are actually very weak, they are very easily scattered all over the place by the molecules of oxygen and nitrogen in the air and we have a blue sky, and by water molecules in the oceans they pass through to reach deeper levels than the longer wavelengths of visible . And then there’s led’s… Anyway, that nothing travels faster than light is a premise of SR and as I was packing away some windows I still had up when looking for info on it, I had this:
http://www.awesomelibrary.org/Classroom/Science/Physics/Particle_Physics/Lorentz_Symmetry.html
2. Lorentz Symmetry Violations and Constraints (Physics.McGill.ca)
“The idea of Coleman and Glashow is the following. Suppose that Loretnz symmetry is not a true symmetry of nature. This open up the possibility that the limiting speeds (the highest speed which can be attained) of different particles, are different from each other. Suppose in particular that the speed of light (of electromagnetic radiation) and the limiting speed of a proton were not the same, and that the speed of a proton were higher. Then it turns out that the proton would lose energy to electromagnetic radiation, until its speed was the same as the speed of light.”
“The way this works is the following. Since the proton is electrically charged, it carries around an electromagnetic field. When the proton moves, the electromagnetic field of the the proton must move with it. The emission of electromagnetic radiation (light) can be understood as that electromagnetic field continuing to propagate, when the proton’s motion is changed by some external force; so every time a proton changes its speed or direction of motion, some of the electromagnetic field accompanying it continues in the old direction and becomes radiation. If a proton were moving faster than the speed of light, then it would ‘outrun’ its own electromagnetic field; without any acceleration being necessary, the electromagnetic field of the proton would get stripped away from the proton and propagate away as photons (electromagnetic radiation). Since the proton is charged, it would continuously regenerate electromagnetic field; but this field would continuously fall behind the proton and be lost as radiation, until the proton slowed down to the speed of light, whereupon the electromagnetic field could keep up with it. This is what happens when a medium, such as water, a crystal, or the air, modifies the speed that light travels; charged particles which travel faster radiate ‘Cherenkov’ light.”
Make of it what you will.
The geometry of space and time that we experience is created by light and is not the same as mathematical geometry,our measurement of space and time changes as we approach the speed of light?