Readers may recall when we covered the first detection of gravitational waves from space, heralding a new era in astronomy. It was big news. Now, a second detection has been announced.
From NASA’s Astronomy Picture of the Day: (h/t to Dr. Leif Svalgaard)
A new sky is becoming visible. When you look up, you see the sky as it appears in light — electromagnetic radiation. But just over the past year, humanity has begun to see our once-familiar sky as it appears in a different type of radiation — gravitational radiation. Today, theLIGO collaboration is reporting the detection of GW151226, the second confirmed flash of gravitational radiation after GW150914, the historic first detection registered three months earlier.
As its name implies, GW151226 was recorded in late December of 2015. It was detected simultaneously by both LIGO facilities in Washington and Louisiana, USA. In the featured video, an animated plot demonstrates how the frequency of GW151226 changed with time during measurement by the Hanford, Washington detector. This GW-emitting system is best fit by two merging black holes with initial masses of about 14 and 8 solar masses at a redshift of roughly 0.09, meaning, if correct, that it took roughly 1.4 billion years for this radiation to reach us.
Note that the brightness and frequency — here mapped into sound — of the gravitational radiation peaks during the last second of the black hole merger. As LIGO continues to operate, as its sensitivity continues to increase, and as other gravitational radiation detectors come online in the next few years, humanity’s new view of the sky will surely change humanity’s understanding of the universe.
Added: I had an interesting discussion with Dr. Leif Svalgaard about gravity that I thought was worth sharing since I found the topic fascinating.
On Wed, Jun 15, 2016 at 10:52 AM, Anthony Watts wrote:
I wonder, what is the speed of Gravity waves?
Thanks,
Anthony
From: Leif Svalgaard
Sent: Wednesday, June 15, 2016 12:04 PM
To: Anthony Watts
Subject: Re: GW151226: A Second Confirmed Source of Gravitational Radiation
The same theory that predicts them [GR] also predicts that they propagate with the speed of light.
Gravitational waves are ‘ripples’ in the fabric of space-time caused by some of the most powerful processes in the universe – colliding black holes, exploding stars, and even the birth of the universe itself. Albert Einstein predicted the existence of gravitational waves in 1916, derived from his general theory of relativity. Einstein’s mathematics showed that massive accelerating objects (such as neutron stars or black holes orbiting each other) would disrupt space-time in such a way that waves of distorted space would radiate from the source. These ripples travel at the speed of light through the universe, carrying information about their origins, as well as clues to the nature of gravity itself.On Wed, Jun 15, 2016 at 12:08 PM, Anthony Watts wrote:
Yes, but how does the universe have gravitational cohesion at that speed? Maybe the waves are speed of light, but the effect of gravity across distance must be instantaneous, otherwise how would galaxies manage to form or stay together?
A
On Wed, Jun 15, 2016 at 12:24 PM, Leif Svalgaard wrote:
The effect of gravity is not instantaneous. We know this because the finite speed is needed be make the predicted positions of planets [and spacecraft] come out right.
Galaxies form because the gravity of Dark Matter helps to draw the intergalactic matter together.
See also http://scienceblogs.com/startswithabang/2010/08/25/what-is-the-speed-of-gravity/
Note: several updates were made to this story about an hour after publication, to correct the title, to replace “gravity waves” with “gravitational waves” so that they weren’t confused with the meteorological term “gravity waves” which I’ve always thought was wrongly named, and to add some new discussion I had with Dr. Svalgaard about the speed of gravity. Also added was an illustration. I’m sorry for the issues, I had partially written the story and set it to auto-publish hours ahead, and then I got distracted by a phone call and didn’t complete the story before it published.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
…Anthony, that should be ” has BEEN detected” ?
[Oh, come on! The second response …. and you are already criticizing the editor?
(Besides, what if the gravity waves have already detected something? ) .mod]
Well, if the Gravity Waves have detected something, they ( the Gravity Waves) should have just come out and told us !! LOL
That’s my fault, got distracted by a phone call during creation of the article, didn’t get to finish editing, and it auto-published on schedule before I could get back to it.
…I blame on the Gravity Wave interference.. :o)
Oops ! I blame IT on the Gravity Wave interference.. :o)…D’oh !
And thanks to the mod for the fix of the headline.
if only he’d fixed it…
(putting away my pedant hat)
Well see I already solved all of that semantics, by simply calling them Einstein Waves or Einsteinian, if you wish to be adjectival. So now it doesn’t matter a hoot, what they are since they are just what Einstein said they would be; and when all of the doubters have left the building, than we can go back to calling them Gravitational waves.
And to Anthony’s second query.
Gravity sucks, just like pulling on a string sucks. But when you pull on the string, nothing actually needs to be moving, the suck is still felt. Likewise gravity still tries to suck all of the materials it can together, even if the bits are flying apart.
I’m still puzzled by the fact that Einstein waves do travel at the speed of light. I have absolutely NO intuitive feel why that is so, but I also do not doubt it. In one sense that might be the most wondrous thing about the whole business. It certainly leads one to ponder, that ultimately gravity must be intimately related to at least the Coulomb force; so maybe a fully integrated universal theory of the four known forces of nature, may eventually be conjured up.
I would say that the Higgs Bosoneers have been thoroughly upstaged by Einstein “Radiation”.
Dr. Leif and his pals, must be getting no sleep time.
G
i like that george, einsteinian .
The “speed of light” is confusingly named. More accurate would be the “speed of particles with zero mass”. I’ll call it “c”. The reason light moves at speed c is because photons have no mass. The particle known as the gluon, which basically helps keep atomic nuclei together, also moves at speed c because it is massless. Similarly, there is a theoretical (but undiscovered) particle which is thought to mediate the gravitational force, called the graviton. This particle would also have zero mass, and hence move at speed c.
Well the value of (c) which is commonly called the speed of light derives directly from Maxwell’s equations for the propagation of electro-magnetic waves, which in turn rests on the values for the permittivity and permeability of free space.
So no need to invoke anything to do with mass.
But I’m happy to accept your version. Of course it does beg the question: Why would any particle of any species that has zero mass happen to travel at any particular speed whatsoever. I understand how (c) derives from (epsilonnought) and (munought) but what are the parameters relating to gravitational radiation that just happen to give the same value for the speed of such waves ? What does gravitation have to do with munought and epsilonnought ??
G
There has to be a “speed” faster than “light”, don’t quantum particles exist in two places at once no matter how far apart they are ? Or am I understanding that the wrong way? I think grav waves travel at “light speed” because they are ” matter” but if quantum particles can be in different places at the same time there has to be a “speed” related to that ( I would call it “existence” rather than “speed”) and faster than light.
Why would any particle of any species that has zero mass happen to travel at any particular speed whatsoever.
If you can work the answer to that question out, we’ll be happy to call you George Einstein Smith.
Now, if we move onto the conjecture that altering one’s velocity relative to one’s original frame of reference dilates time, and that traveling at the speed of light dilates time to the point where it appears to have stopped passing entirely relative to its rate of progression experienced by observers in the original frame of reference, does it follow that particles with zero mass traveling at c move between points A and B instantaneously from the standpoint of a theoretical massless observer traveling alongside such particles? In other words, would a conscious massless particle experience no passing of time whatsoever, even on a journey across billions of lightyears?
Tim, correct. Photons don’t experience “time”.
As for velocity, what speed do waves on water propagate(retorical)? Whatever it is, it’s not based on water traveling (other than up and down maybe).
Alex
June 15, 2016 at 6:13 pm
Too be really pedantic you should say the speed of light in the medium in which the massless boson travels.
how the heck do planets stay in orbit if gravity moves at c ? I mean.. if the light from the sun takes 8 min to get to us, wouldn’t the ‘gravity’ take 8 too? The more I read of the LIGO indirect observations being claimed as direct observations, the more I doubt what I was taught as fact at uni, and the less feasible it all sounds :/
” how the heck do planets stay in orbit if gravity moves at c ?”
Because space is curved in front of the planet already from 8 minutes prior.
“””””…..micro6500
June 15, 2016 at 11:08 pm …..”””””
In deep water, if the surface moves up from the neutral flat surface level, it experiences a restoring force due to the earth’s gravity (gravity waves) and that force is constant, independent of displacement for small displacements. But simple harmonic motion requires a restoring force that is proportional to the displacement, and opposite in direction to the displacement.
Ergo, such water “gravity waves” cannot be SHM giving rise to sinusoidal solutions that travel at some fixed velocity independent of frequency. So deep water ocean wave propagation is dispersive, and the different frequencies travel at different speeds.
BUT ! in addition to the force of gravity acting on a displaced surface, there is also a surface tension force, that tries to return the surface to its minimum area condition which is flat.
In deep water, the gravity effect far outweighs the surface tension effect; but as the water shallows, the surface tension restoring force becomes more significant, and results in higher frequency waves travelling even faster.
This causes the wave shape to change from nearly sinusoidal, to a triangular form with the faster waves piling water up in front. This eventually results in the leading edge becoming vertical and tipping over the front of the wave leading to breakers.
Well it’s a bit more complicated than that, but you get the general idea. Water waves are quite complex.
G
Good to see NASA doing something besides global warming and Muslim outreach.
Wait for it … no doubt they are working on the link to human CO2 emissions and are waiting for the right time to declare it.
… and good to see WUWT reporting on some science instead of the now common-place policital rants from Eric Worrall.
Is there enough time sensitivity with these instruments to make an estimate of the direction from which the gravity wave came?
Generally but not precisely. Louisiana is too close to Washington. That will change when the European LIGO goes on line. The separation is several fold greater, and the three detectors will be able to triangulate. Was discussed in some of the other articles today announcing the second detection.
Might be interesting to be able to turn the telescopes to the same area and see the after glow of whatever caused the gravity wave.
Triangulation from three positions on earth, not with a shred of accuracy. We’d need two satellites light years from earth to create any sort of even remotely accurate triangulation of position
Yes and no. With 2 sensors, they can determine a plane. LIGO is collaborating with other interferometry groups that may lead to triangulation.
This is where instrumentation on the Moon could come in handy. I don’t know why we haven’t put a big telescope on the moon by now?
why we haven’t put a big telescope on the moon by now
====================
NASA blew its budget with the mission to planet earth back in the early 70’s. Turns out you don’t need a very powerful telescope to view earth. But all those earth scientists studying earth’s climate cost a pile. Something had to go. It wasn’t the climate scientists.
it matters not, there is not even remotely enough distance to make any accurate measurement.
We’d need 2 more observational stations on two of the the nearest stars to get anywhere near a ball park figure, any claim to the contrary is dishonest at best
The predicted signals for the two different interferometer locations are themselves different, and dependent on the direction the waves actually come from, so unraveling the match to the two signals, comes with a rough idea of a source direction. The two interferometers are oriented differently in 3-D space, due to the earth curvature, so each “antenna” sees the signal coming from a different angle which alters the expected signal.
So they do get a clue as to source location, which may ultimately lead to a visible (Izzat Coulomb Radiation) object being identified as the source. (maybe).
G
Thinking of how X-rays have gone from a simple plate exposure to 3D computer generated images, it’s going to be interesting to see the use of gravity wave imaging will develope in the future.
Gravitational waves, not gravity waves
That’s my meteorological bias speaking see: http://www.atoptics.co.uk/highsky/hgrav.htm
I’ve always thought that was the wrong name for that phenomenon.
Anthony Watts June 15, 2016 at 1:46 pm
That’s my meteorological bias speaking see: http://www.atoptics.co.uk/highsky/hgrav.htm
I’ve always thought that was the wrong name for that phenomenon.
—————————————————————————–
Interesting Anthony, that little snippet states “solar radiation”? as producing gravity waves?
Sun has a got alot more going on than that that would disturb the atmospheric pond, so to speak.
Atmospheric Gravity Waves
http://www.atoptics.co.uk/highsky/hgrav.htm
“””..What triggers them? The ‘stones into the pond’ are disturbances far below in the troposphere, for example, wind flow over mountain ranges and violent thunderstorms. Jet stream shear and solar radiation are other sources. An initial small amplitude at the tropopause increases with height until the waves break in the mesosphere and lower thermosphere. Their wavelengths can range up to thousands of kilometres. Their periods range from a few minutes to days…”””
Correct.
“Gravity waves” are ripples propagating on a fluid surface where the restoring force to the wave motion is gravity. These waves are not the same as the hypothetical waves emitted due to acceleration of mass, which should properly be called “gravitational waves”.
For example, here are gravity waves in the Earth’s atmosphere, i.e. air acting like a fluid:
http://67.media.tumblr.com/354670232d66403ef3461550e067ce01/tumblr_o2e5mh7d741sq04bjo1_500.jpg
That’s air not gravity that causes that sorry.
@Helsinki Mark
That’s air not gravity that causes that sorry.
Sorry, you are simply wrong. Atmospheric gravity waves (aka buoyancy waves) are indeed caused by gravity.
Gravity is the restoring force for laminar flows of air which have somehow been perturbed vertically (e.g. air moving over a mountain). At equilibrium, air density decreases with altitude. So any upwardly displaced parcels are temporarily more dense than the surrounding air and start to sink immediately, seeking equilibrium. But overshoot equlibrium, of course, creating the oscillating ripples we call gravity waves.
http://www.physics.uwo.ca/~whocking/p103/grav_wav.html
… here’s a graphic example of atmospheric gravity waves
Is this gravity pulse the same in profile as the model often injected to calibrate the system and is it the same in profile to the pulse that was not injected months back?
Except for the different masses, yes. It is the rising chirp predicted by the physics and similar to the first detection. This was pointed out in other articles today on the second detection.
The received signal is dependent on the precise event that launched the radiation, and it is different for the two locations. They use massive computation to determine (or try to) the precise parameters of the event that can create both of those signals. It’s a very clever system of unraveling an analog signal using matched filtering.
In effect they have two photographs (or videos) of “something” that went whizzing by. And they are looking at those two different videos, and asking, ” What the hell was that anyway ?”
Only one plausible event can create those two videos. They’ll get better at deciphering these things as they get more of them to look at or listen to, or however one reacts to Einstein waves.
G
I know the universe is a big place, but to have two sets of double black holes merge within one year says there are a heck of a lot of black holes out there. Maybe we have got the whole missing dark matter thing wrong? Black hole dark is very different than WIMP dark.
Heck of a lot of galaxies out there, each with it’s own black hole(s).
There are indeed a heck of a lot of BH out there, and BH-pairs and BH mass. The expected detection rate was in the announcement material for GW150914.
Consider the area of a 10 billion light year sphere. That is a bit over 12.56*10^20 square light years. If you think of a shell that is a billion or two light years thick, you get out to things measured in 10^30 cubic light years. You can cram a lot of “stuff” into that sort of volume.
ShrNfr June 15, 2016 at 3:48 pm
..You can cram a lot of “stuff” into that sort of volume.
——————————————-
Yes indeed..
Which spiral arm of the Milky Way contains our sun?
By Deborah Byrd in SPACE | May 20, 2014
Many know our Milky Way is a spiral galaxy. But where within this vast spiral structure do our sun and Earth reside?
http://en.es-static.us/upl/2013/01/Orion_Spur_sun.png
We live in an island of stars called the Milky Way, and many know that our Milky Way is a spiral galaxy. In fact, it’s a barred spiral galaxy, which means that our galaxy probably has just two major spiral arms, plus a central bar that astronomers are only now beginning to understand. But where within this vast spiral structure do our sun and its planets reside? Our galaxy is about 100,000 light-years wide. We’re about 25,000 light-years from the center of the galaxy. It turns out we’re not located in one of the Milky Way’s two primary spiral arms. Instead, we’re located in a minor arm of the galaxy. Our local spiral arm is sometimes Orion Arm, or sometimes the Orion Spur. It’s between the Sagittarius and Perseus Arms of the Milky Way. The image below shows it…
http://earthsky.org/space/does-our-sun-reside-in-a-spiral-arm-of-the-milky-way-galaxy
Milky Way Galaxy Collided with Andromeda 10 Billion Years Ago, Astronomers Suggest
Jul 4, 2013 by News Staff
http://cdn.sci-news.com/images/enlarge/image_1196_1e-milky-way.jpg
An artist’s impression shows a stage in the merger between Milky Way Galaxy and the neighboring Andromeda galaxy (NASA / ESA / Z. Levay / R. van der Marel / STScI / T. Hallas / A. Mellinger)
..The Milky Way is part of a group of galaxies called the Local Group. Cosmologists believe that most of the mass of the group is invisible, made of so-called dark matter. They suggest that across the whole Universe, this matter outweighs ‘normal’ matter by a factor of five. The dark matter in both Andromeda and the Milky Way then makes the gravitational pull between the galaxies strong enough to overcome the expansion of the cosmos, so that they are now moving towards each other at around 100 km per second, heading for a collision 3 billion years in the future. But this model is based on the conventional model of gravity and struggles to explain some properties of the galaxies we see around us.
Dr Zhao and his colleagues argue that at present the only way to successfully predict the total gravitational pull of any galaxy or small galaxy group, before measuring the motion of stars and gas in it, is to make use of a model first proposed by Prof Mordehai Milgrom of the Weizmann Institute in Israel in 1983. This theory, named Modified Newtonian Dynamics (MOND), describes how gravity behaves differently on the largest scales, diverging from the predictions made by Newton and Einstein.
The team has for the first time used MOND to calculate the motion of Local Group galaxies. Their work suggests that the Milky Way and Andromeda had a close encounter about 10 billion years ago. If gravity conforms to the conventional model on the largest scales then taking into account the supposed additional pull of dark matter, the two galaxies would have merged….
Bold emphasis by me..
Just makin some waves..
“The 2006 observation of a pair of colliding galaxy clusters known as the “Bullet Cluster” poses a significant challenge for all theories proposing a modified gravity solution to the missing mass problem, including MOND.” So MOND is generally not an acceptable modification of Newtonian Gravity.
“Space is big. Really big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist, but that’s just peanuts to space.”
Douglas Adams, The Hitchhiker’s Guide to the Galaxy
I thought we were going to crash together a few billion years from now and it has not happened yet? That pic is a ” virtual” to predict rather than a past event.
Catch the wave.
The are now measuring ‘ripples’ in the ‘fabric’ of ‘space-time’.
These effects are ‘sub-atomically small’.
Sounds very very like ‘astrology’ to me…
Well they are actually astronomically large. It is the antenna signal that we can detect that is sub-atomically small.
Come to think of it, Astrology is also astronomically large; as big as the whole damn zodiac.
You can go back to sleep Charles.
G
Let me get this straight then…we are on a planet with a massive core of iron or nickel, we have a moon which passes over our heads once a day, and the planet itself is orbiting a ‘star’….orbited by other planets some of which are enormously more massive ours…and all that is happening inside inside a GALAXY…surrounded by other galaxies each with its own supermassive Black Hole?
And these people are saying they’ve ‘detected’ ripples ‘in the fabric of ‘space time’ from a collision event that took place on the far side of the universe…hundreds of millions of years ago?
This event was so massive that it did not appear on any other observational spectra…other than emitting a ‘gravity wave’.
Did I miss anything there?
Maybe the sound of a tree falling in a forest when no-one is around…or maybe the sound of one hand clapping?
charles
You really missed something.
What kind of spectral emissions would you expect to see from the collision of two black holes?
charles nelson wrote:
If the space between two black holes is empty, I suspect it would be, there wouldn’t be much other radiation source material around the collision. If there is material further out that does respond, any photons can be absorbed by gas and dust clouds between those sources and us.
One neat thing about gravitational waves is that we don’t really have anything that can absorb them. About the only thing that can happen is for them to be deflected by heavy objects.
So yes, we can see gravitational events when no photons could reach us. However, assuming that some do, they could be very easy to miss. we don’t have the telescope capacity to monitor the whole sky at high resolution.
It took quite a while to go from knowing about gamma ray bursts to observing them at longer wavelengths. See http://www.nasa.gov/mission_pages/swift/bursts/supergiant-stars.html
I agree, charles . . this is unconvincing to me. I suspect it’s actual deception, frankly.
And your expertise to support that opinion is?
I’m a human being.
Deception!?
From the Big Science community!?
Ad in the fact that global warming is all about 0.1 – 0.2 degrees Celsius ? These measurements are so tiny they are laughable. But it makes me wonder why we are doing this type of research ( like the cyclotron colliders) in the first place.
From the WUWT article regarding the first detection, this link;
http://www.sciencemag.org/news/2016/02/here-s-first-person-spot-those-gravitational-waves
‘Here’s the first person to spot those gravitational waves’
…
“In fact, the signal was so strong that Drago didn’t believe it was real—and with good reason. A gravitational wave from a distance source stretches space by an infinitesimal amount, and to detect that rhythmic stretching LIGO employs two gigantic optical devices called interferometers, which essentially act as gigantic rulers. To test the incredibly complicated devices, LIGO physicists have developed mechanical systems to give them a shake and “inject” a fake signal. The signal Drago saw was so perfect it seemed too good to be true, he says. “No one was expecting something so huge, so I was assuming that it was an injection.”
Here’s where the story departs from the previously prepared script. Injections can be done in two ways: out in the open when researchers are tuning up the machines and secretly when they are taking data. Those latter “blind injections” are meant to keep researchers on their toes. Only four LIGO leaders know when such injections are made, and that information is supposed to be revealed only after a potential signal has been thoroughly scrutinized and written up for publication. That’s how things unfolded in 2010, when LIGO researchers learned at the last minute that a possible signal was in fact a blind injection. So if all had gone as anticipated, Drago might have simply noted the alert and carried on as usual, assuming the truth would come out in the end.”
…
“The team spent much longer than that making sure they had not somehow been fooled by a signal that had been injected either inadvertently or even as part of some elaborate prank. But such scenarios proved untenable, Reitze says. “You’d need a whole team of insiders with a wide variety of technical abilities,” he says.”
Note the two potentials mentioned there, please; … injected either inadvertently or even as part of some elaborate prank … There is an obvious (to my mind) third potential.
So JohnKnight our answer to my question is: None.
The gravitational force is incredibly weak. It is many orders of magnitude weaker than the Coulomb force between electric charges.
Early experiments to directly measure (G) in the laboratory used a pair of very large spherical masses, and a pair of much smaller masses forming a dumbbell that could twist on a very thin fused quartz fiber forming a torsion pendulum. I forget the details, of the experiment, but it directly measured the attraction between the large balls and the smaller balls, in terms of the frequency of oscillation of the torsional pendulum. The gravity force between the small and large mass is miniscule.
So these catastrophic collision events result in Einstein waves originating from a relatively small source a heck of a long way away. That radiation presumably diffracts, just like EM radiation does, so it spreads out in some radiation pattern, about which I know absolutely nowt.
By the time such radiation gets to us, it is incredibly attenuated, just as is the solar energy from the sun travelling 93 million miles.
Then that incredibly weak fluctuating gravitational force (ripple) interacts with a pitifully small mass (relative to black holes) in the form of a quartz mirror (I believe), and moves it an unbelievably small amount; sub atomic amount.
Only truly ingenious instrumentation allows that tiny movement of the mirror to be observed and even measured.
But ordinary mortals who can’t even guess how little six inches really is, can not be expected to understand how such miniscule changes can be observed and measured; but now we know they can be.
G
I’m a mere mortal, and can understand how such minuscule changes can be observed and measured (since I read about it) . . but I can’t for the life of me understand why any sane person would think mere mortals would have trouble guessing how little six inches really is . . or why they would not notice the third potential I mentioned.
But, it seems to me there is a form of human authority worship, which prevents otherwise rational people from realizing those above them in the hierarchy of human authority can be tempted by things like fame and fortune, ideological/political considerations, peer pressure . . and a little six inches ; )
Imagine if you will, a pair of identical twin young ladies. This pair are so indistinguishable, they even have the same fingerprints. And these ladies are champion free style swimmers. In 100 races counting heats and finals, neither one of them has ever been beaten; even by her sister.
if they both race, they always win, and they always dead heat. In adjacent lanes, it looks like s split image of one person, and their heads sit right over each other in the photo finish photos.
So they are invited to a small meet to inaugurate a new 50 meter Olympic size swimming pool.
Just eight entrants invited, so just a single final race. Now their free style specialty is the 1500 meters.
So Jane draws lane one, and Jill draws lane eight, on the far side of the pool.
Again they set off like synchronized swimmers with their stroke for stroke exactly matching.
Well as the race approaches the end, it seems apparent o the crowd, that they are a tiny bit out of synch, And when they finally touch at the end, Jill beats Jane to the touch by a small margin.
The photo finish shows that their caps are separated by about 30 mm; a little over an inch in the 1500 meter race.
Well Jane cries foul and asserts that she swam her heart out, and she knows she was as fast as her sister.
So the authorities decide to get out their laser theodolites and instruments and re-measure the pool.
A cube beam splitter sitting on the start end wall, which is a solid glass insert window, sends a beam to the far end 50 meters away, and a flat mirror, laying on the glass at that end returns the beam to the cube to mix with the transmitted split beam.
Sure enough, the two ends of the pool are not parallel. They measure the start end corner angles, and those are both 90 deg. to better than one arc second, but the far end is tilted about 15 arc seconds or so, so over the 14 meters separating the lane one, and lane eight centers, the pool length shrinks by one silly mm. So Jill was turning 1 mm short of Jane on every lap, and over the 1500 meters, she accumulated 30 mm of an apparent lead. she actually swum a 30 mm shorter race than Jane.
No who could have guessed that one side of the pool was a mm longer than the other. But after enough round trips that short distance movement, added up to an observable difference.
Just imagine how much a laser beam can gain on itself after making hundreds or thousands of round trips in a laser cavity that got shortened by a fraction of an atom diameter, due to an Einstein Wave disturbance of one of the mirrors followed by a later move of the other end mirror.
So just because some of you can’t even imagine how such metrology feats are carried out, don’t assume that other people don’t know how to do it.
Put it down to your ignorance; not their lack of skill .
G
Truly sincere thanks to Leif and Anthony. It may be too esoteric and complicated for me to pursue but I am rather thrilled at our ability to produce SCIENCE that may lead to greater knowledge and predict the future. I understand some of it. Part of it I must leave to better educated ( and more committed) fellow people. This sort of learning gives me hope for the future.
This is not “snarc”: If all science was so nearly non-political we might solve many pressing problems.
This reminds me of this clip. Do we discuss infinity here?
This all eases my mind somewhat…………… maybe I don’t really weigh 16 stone (224 pounds for our colonial cousins), maybe I’m just a magnet for gravitational waves
Svalgaard,
“Galaxies form because the gravity of Dark Matter helps to draw the intergalactic matter together.” You make it sound as if this is well-established, which it most certainly is NOT. There is no direct evidence of Dark Matter, and the evidence for Dark Energy took a huge blow last year. Standing outside of Science and watching, as many engineers do, I perceive that MainStreamScientists tend to work a meme to death, getting lots of grants and Professorships, until something knocks it down and they all go off in a new direction.
Professor Brown at Duke called Dark Energy and Dark Matter “Fairy Dust Models.” I agree with him.
Dark matter that does not interact with anything else but just provides missing gravity needed to reconcile a failing model with observations is what is more generally called a fudge factor. Fairy fudge, perhaps.
Fudge is a polite term for another stick, brown substance.
Well, Dark Matter is actually well-established by its effect. I don’t know what you mean by ‘direct evidence’. Here is some ‘good evidence’: http://www.leif.org/EOS/CosmicSoundWaves.pdf and a bit more technical one: http://www.leif.org/EOS/1411-3556-Dark-Matter.pdf “that provides one of the greatest direct proofs for dark matter, such as Bullet cluster”.
lsvalgaard June 15, 2016 at 5:00 pm
————————————————–
Thanks Dr. S., how much more timely could that article have been?
Re: recent images I’ve posted of Milkyway merger with M31 Andromeda.
Haven’t gotten to the Bullet cluster, in the article, that’s what drew me in to begin with.
DARK MATTER IN COSMOLOGY
VLADIMIR LUKOVIC PAOLO CABELLA NICOLA VITTORIO
“””One of uncertainties still is the question of existence
of distinctive separation between the disk (luminous or dark) and the halo.
The size and the shape of the halo in double systems is another tricky question. For
example, a Milky Way halo extends at least 200 kpc and it is getting close to the
half-way distance between the Galaxy and Andromeda, 350 kpc. And if halos are
as large as those suggested by the gravitational distortion of background galaxies
seen in the vicinity of foreground, then the halo of our Galaxy may brush the equivalently
large halo of M31. In addition, few spiral galaxies exhibit a true Keplerian
decline in their rotation velocities.””” [Andromeda (M31)]
http://www.leif.org/EOS/1411-3556-Dark-Matter.pdf
Existence is at least postulated by the observation of a phenomenon, that could be explained, by such an existence.
ANYTHING that EXISTS must be producing some sort of observable effect, which leads us to postulate the cause of that phenomenon. In the absence of any unexplained observation there is no need to postulate that something else must exist to cause that.
So as you say Dr. S, the observation of the effect is itself the proof of the existence of a causal agent. Of what, is where we get to scratch our heads.
G
The distribution of dark matter is the problem. Its distribution is whatever the gravity-based observations say it is… that’s not science, that’s a fudge. There needs to be at least two independent ways of detecting a distribution of ‘dark’ matter or you are just making stuff up.
Personally I’m a fan of the Unruh event horizon theory, it explains a lot of stuff with no fudges and is testable in multiple ways. The summary of this theory is that the minimum acceleration of any object is on the order of 2e-10 m/s due to the limit that Unruh waves cannot go beyond the event horizon of the universe (conservation of information). This explains a lot of things like some unexplained orbital mechanics issues, the Pioneer anomaly, rotation of galaxies and other low-acceleration regimes.
More reading here: http://physicsfromtheedge.blogspot.com/ (see papers linked from there)
Peter
correction: min acceleration a=6.9×10^-10 m/s^2. I accidentally cited the MOND constant, and MiHsC is NOT MOND.
Svalgaard,
How do you decide which studies to believe and which not to believe?
“The surprising substructure of Abell 520 was reported in 2007 from a weak gravitational lensing study based on Canada-France-Hawaii-Telescope (CFHT) imaging data. It was surprising because the study found the “dark core” with a significant amount of mass in the region, where there is no concentration of bright cluster galaxies. No conventional understanding of dark matter can explain this peculiar concentration of dark matter. “
Science is a highly interconnected web of observations, theories, and [yes] speculation [at the frontiers of knowledge]. Tentative conclusions are drawn that coherently connect the various pieces. From the conclusions models are constructed that provide predictions about what observations should show. If the predictions bear out, we gain confidence in the ‘correctness’ or, at least, the usefulness of our models and the knowledge they express.
If the predictions bear out, we gain confidence in the ‘correctness’ or, at least, the usefulness of our models and the knowledge they express.
The problem is there isn’t a good prediction on the distribution of dark matter. It’s just whatever is observed via lensing, rotation, et. al. …. a chicken&egg problem.
Peter
Well, observation beats prediction. But Dark Matter is actually predicted, e.g. from the acoustic baryon peaks: http://www.leif.org/EOS/CosmicSoundWaves.png
Svalgaard is indeed a funny one. He resolutely denies any possibility that the Sun affects the Earth’s climate, yet here he enthusiastically embraces the idea that we can detect sub atomic ripples in the fabric of space time!
goes by what the data shows.
Leif. Can the status of the theory of Dark Matter be summarised as follows? There is an observed phenomenon which is difficult to explain. If there was such a thing as Dark Matter, then it would explain the phenomenon. By assuming the existence of Dark Matter we can make predictions. Those predictions, to date, have been tested successfully. Dark Matter is therefore regarded as a useful theory (until such time as it may be disproved).
To put the above summary into context, I submit the following: There is an observed phenomenon which is difficult to explain, namely, stuff falls when you drop it.. If there was such a thing as Gravity, then it would explain the phenomenon. By assuming the existence of Gravity we can make predictions. Those predictions, to date, have been tested successfully. Gravity is therefore regarded as a useful theory (until such time as it may be disproved).
There have been useful theories in the past which have been disproved, or significantly modified, so there is no suggestion here that a useful theory will not at some time be disproved. Something which people often fail to recognise when using useful theories.
No, that is too simple-minded. There are many phenomena that directly show that dark matter exists, i.e. that there exists something which responds to gravity but not to electromagnetism. From the observed density of dark matter we can predict the acoustic baryon peaks, see e.g. http://www.astro.ucla.edu/~wright/BAO-cosmology.html or http://background.uchicago.edu/~whu/intermediate/driving2.html
Interestingly, what looks like a gravity wave on the surface of the sun. Hopefully the like will jump to 8:11 min into the video where the image is shown.
https://youtu.be/9TOKo7Ik9f8?t=491
Not saying that I find Dr Robitaille’s claims that this ‘proves’ the solar surface is liquid very convincing since , as Johanus posted above, we have plenty of evidence of atmspheric gravity waves here on Earth.
But the image, courtesy of SOHO is very interesting.
I think fluid is the word; NOT liquid !
G
‘Fluid’ can apply to gas as well as liquid, so I think Mr. Robitaille is intentionally differentiating with his choice of terms there, george.
I think Robitaille is failing to realise that this is fluid phenomenon rather than a liquid phenomenon and incorrectly jumping to the conclusion that this ‘proves’ the surface of the sun is liquid.
He says some other fairly silly stuff without proper analysis and ends with some kind of creationist argument. It looks like his belief system is clouding his analysis and bais confirmation takes over.
However, I find the pond splash on the sun very interesting and I’m sure something can be learnt from it.
JohnKnight
June 15, 2016 at 9:43 pm
‘Fluid’ can apply to gas as well as liquid, so I think Mr. Robitaille is intentionally differentiating with his choice of terms there, george.
_________________________________________________________
Not really if you actually look at the whole piece, transverse waves are not a gas phenomenon. Fluid is often used as a synonym for “liquid” btw, though technically all fluids cant resist any shear force.
So you are injecting pointless assertions into the conversation because? You dont agree with Robitaille?
He is a rare breed, he builds experiments and theories. He’s built an MRI himself and broke the radiological imaging record, doubled it in fact when everyone told him he was mad, was going to fry people, current MRI resolution is down to Robitaille, and as such he has more expertise on how to capture radiation data like CBR than NASA have.
Most of the people who disagree with Robitaille have never been in a lab ironically, he is an empirical scientist and engineer
Well the existence of “gravity waves” is NOT proof of the presence of a LIQUID, since any FLUID can exhibit gravity waves.
G
Yes another inconvenient truth, transverse waves.
Dark Matter is the astronomy joke of this century. It was a desperate attempt to explain why their theory of galaxies was right.
This gravitational nonsense is why they also came up with strange matter, because a new matter not based on physics (like a singularity for black holes) it is “strange”, or more accurately entirely made up from thin air. like dark matter.
Also incorrectly stated is the claim finite speed is needed for calculations, when in fact the calculations rely on finite speed not the universe
Maybe not proving a fluid, but certainly proving not a gas.
Dark Matter & Energy are just God’s way of being adjectival with us.
But God does not play dice with the universe…does she? Maybe these are just pool balls to her. galactic roulette?
There is more evidence for gravitational waves than for a god.
Thanks for the politically correct form of God, but in fact God is now transgender with the ‘preferred pronoun’ being “they” , please try to keep up.
So we should now reword this :
“God does not play dice with the universe…does they. ”
At some stage God will get tired of being screwed around by all these politically correct idiots and take care of the situation in a similar way to what He did with Sodom and Gomorrah.
Depends on who you talk to.
I bet US$1Trillion that before my life is out these turn out to be electromagnetic in nature and have nothing what-so-ever to do with the theoretical structure that is called a black hole.
If this doesn’t happen in my lifetime, feel free to come and collect from my estate.
Willful ignorance is a terrible thing. And diminishes your life as a sentient being.
Pseudoscience needs defending….who you gonna call?
I could not have said it better myself.
Willful ignorance is a terrible thing.
=======================
Similar to quantum
According to the definition of a black hole, the orbital speed of any object at the event horizon is the speed of light.
And according to GR, an object at the speed of light experiences infinite time dilation. Thus, any object orbiting just above the event horizon is travelling at so close to the speed of light that it will take millions of years in our time before a single second of time passes for the object orbiting the black hole.
So, how can two black holes in orbit around each other ever merge in our lifetimes, or even in the lifetime of the universe? Why is their relative orbital speeds not near light speed? Why does time dilation not effectively
ferdberple, it looks like you got cut off, or was it time dilation? I believe the answer to your paradox is that time slows down for the black holes but not for us outside observers. It’s essentially the problem of time slowing down for an observer approaching light speed. To him, everything outside his vehicle would appear to slow down and almost stop. To us, he’s going mucho fast. So the black holes think they’re circling each other forever, but we see them go “Slurp!”
Who said the two black holes were orbiting each other or one orbiting the other ??
They were on a collision course.
The “orbit” of an artillery shell, is (neglecting air resistance) NOT a parabola; it IS an ellipse; but the perihelion is underground on the far side of the earth that the shell can never reach.
G
Never make a bet that can be easily won by killing you. ^¿^
The gravity wave’s translation to sight and sound appears to be a hockey stick.
Perhaps the hockey stick has hit you in the head as you seem to confuse gravity wave with gravitational wave.
On line dictionaries allow for more than one application:
“grav·i·ty wave
noun Physics
noun: gravity wave; plural noun: gravity waves
1. a hypothetical wave carrying gravitational energy, postulated by Einstein to be emitted when a massive body is accelerated.
2. a wave propagated on a liquid surface or in a fluid through the effects of gravity.”
So you will deliberately continue to use the wrong terminology based on an “on line dictionary”. Stubborn? Egotistical? Or just to be annoying?
Annoying pedants is it’s own reward.
“Annoying pedants is it’s own reward.”
The proper word is “its”, not “it’s”, since “its” is the possessive form and “it’s” is actually the contraction for “it is”, which wouldn’t make any sense in this–
Oh. I see what you did there.
You’re SO annoying! 🙂
It is too early to know with 100% certainty which term will be the ultimate choice in the future. The twists and turns that determine Language use are dependent on many factors – including the internet! Know-it-alls on present use may or may not be correct in the long run.
The effect of gravity is not instantaneous. We know this because the finite speed is needed be make the predicted positions of planets [and spacecraft] come out right.
=================
Is that correct? It is my understanding that:
1. Newtonian mechanics are used for spacecraft.
2. Einstein’s solution/correction for the orbit of Mercury was not dependent on the speed of gravity. Rather, Einstein solved the orbit of Mercury as a straight line (geodesic) in curved space.
The actual gravity well produced by the sun is relatively static. It moves slightly as the sun wobbles slightly around the center of mass of the solar system, but Einstein ignored this in his solution, because the wobble is miniscule compared to the time and distances involved.
Whether the wobble propagated instantaneously, or with finite speed, it would have made no measureable difference to Einstein’s correction for Planetary orbits. Thus, Einstein’s corrections for planetary orbits is for all practical purposes were independent of the speed of gravity, which is one reason why it has proven so hard to measure the speed of gravity.
Everybody likes to talk about curvature in the fabric of space-time as if the existence of this space-time fabric has been amply demonstrated, or at any rate could be taken for granted. Then when I point out that there isn’t really any such thing, I’m bombarded with the all-excusing ace of trumps, “Well it doesn’t make any difference because the math derived from the theory fits the observations, and that’s all that matters.” This is preposterous.
Notwithstanding the fact that these “observations” are educed out of statistical noise at the subatomic scale by algorithms which not surprisingly conclude that the manufactured data are best explained by colliding black holes billions of light-years away (which is what they’re programmed to do after all), it is not cricket to claim that, on the one hand, these data validate Einstein’s theory because the theory predicted their existence and, on the other hand, to claim that we know exactly what these data are because that is what Einstein’s theory predicts. This is just flat-out circular argumentation. Nobody has any idea what this signal is. I suspect it is nothing; but even if it is something, it is certainly not a gravitational wave because the latter do not exist.
Furthermore, regarding the idea expressed above that the gravitational force propagates at a finite speed, there is not a shred of evidence anywhere in existence that this is so. In fact, it is fundamentally necessary that gravitational forces act instantaneously; if this were not so then there would be no stable orbits and no coherent description of gravity at all.
Being and Time, you are correct that that the effect of the gravity field for non relativistic velocities is instantaneous.
The gravity waves that are being detected are a change in the slope of the field, which does propagate at the speed of light. This is because the masses and velocities involved are massive.
You might also be interested to learn that clocks in satellites in orbit run FASTER than clocks down in the gravity well on earth, where acceleration is more important than velocity relatively speaking ^^
Yup. GPS satellite orbits follow Newton, but their timing signals must follow Einstein. Else, would be off by about 10 km per day and useless.
I’m going to jump on that claim of atomic clocks adjusted within GPS satellites to fix relativistic errors ..
http://www.gps.gov/governance/advisory/members/hatch/ Ron Hatch (an engineer with numerous GPS patents) has openly stated for years that GPS has nothing to do with relativistic time adjustments.
http://alternativephysics.org/book/GPSmythology.htm Bottom of the page – the error factors are irrelevant as they’re corrected by earth bound reference stations on a weekly basis.
http://www.ldolphin.org/vanFlandern/
If you work out the claimed 38 microseconds Vs 0ms you’ll see the error is marginal.
the speed of light and EMF through air is not c
BT, you are ignorantly wrong. Gravitational lensing has been well established for many decades. Ditto Mercury precession. Both are explained by general relativity, and nothing else. GPS works only because of application of Einstein’s special relativity.
Up your game here, or take it to stupid sites like SKS.
“Both are explained by general relativity, and nothing else. ”
interesting practical reasoning.
absent a better explanation, we are compelled to accept an explanation that works.
Why not? It’s not like we are committing the future of our economy on the answer.
Correct me if I’m wrong, but in the phrase “massive accelerating objects”, doesn’t the word “massive” just mean “having mass”, not “extra-heavy”? If I’m right, the Moon and Earth are radiating gravitational waves too. “Extra-heavy” just comes into it just to make the signal strength big enough for us to detect.
Yes but. GR says that ‘detectible’ gravitational waves only come from supermassive events. Remember, whenever you fall down, Earth also falls up. But Newton’s equations say you will fall down a lot, and the Earth will fall up imperceptibly, owing to the ginormous difference in mass/ inertia.
I have weighed the entire earth on my bathroom scale. It used to weigh 180 pounds, but now it only weighs 165, but I feel much healthier now.
If I forget to put the scale on the bottom of my shoes before I put the earth on top of it, then the earth only weighs two pounds. I guess my bathroom scale just doesn’t have much gravity, unless I give it some help.
G
“But Newton’s equations say you will fall down a lot, and the Earth will fall up imperceptibly…”
Obviously you’re unfamiliar with Chuck Norris:
Re: speed of gravity, here is an interesting study which, if I understand the author correctly, implies that some gravitational effects are transmitted at speeds MUCH higher than c.
http://ldolphin.org/vanFlandern/gravityspeed.html
Let me get this straight then…we are on a planet with a massive core of iron or nickel, we have a moon which passes over our heads once a day, and the planet itself is orbiting a ‘star’….orbited by other planets some of which are enormously more massive ours…and all that is happening inside inside a GALAXY…surrounded by other galaxies each with its own supermassive Black Hole?
And these people are saying they’ve ‘detected’ ripples ‘in the fabric of ‘space time’, from a collision event that took place on the far side of the universe…hundreds of millions of years ago?
This event was so massive that it did not appear on any other observational spectra…other than emitting a ‘gravity wave’.
Did I miss anything there?
Maybe the sound of a tree falling in a forest when no-one is around…or maybe the sound of one hand clapping?
We also have light telescopes that can see light from stars so faint that the average light bulb would drown them out. We have RF telescopes that can see radio emissions from the universe that any normal radio or TV station emission would drown out completely.
What you might want to do is get an education and learn how we see the events through emissions that yes would drown out those signals.
So your statement is completely imbecilic … did we miss anything there?
LDB I too was taught the theories of black holes and so forth while studying physics at university, and I too swallowed it wholesale. It has been some 25+ years since then and I happened to be lying under a car thinking about a lesson in optical physics I taught when it struck me – the latest photographs of the moon exhibited some diffraction but no lensing – and I wondered why not. This led me to thinking that many planets and suns had deep atmospheres and light could simply be refracting through the atmosphere to ‘bend’ through simple optical physics and not because light had mass (something that always troubled me)
At this point I could have gone inside, read a physics text, consoled myself that everything is exactly as I was taught and go about my day, but trained as a practitioner of the philosophy of science and filled with natural curiosity, instead I went looking to see whether these thoughts I had could be disproved – and much to my surprise I found more than a few physicists out there had the same thoughts as myself, and were also unable to disprove this idea.
https://www.thunderbolts.info/wp/2015/11/26/lensing-by-refraction-not-gravity/ It’s hard to establish an experiment to conclude either way.. I can think of one, but I don’t have access to the material that slows light as much as would be needed (Bose-Einstein Condensate or the vapor of rubidium gas) – all you’d do is determine whether light passing through the media falls toward toward Earth at the standard trajectory you’d expect in a gravitational field rather than passing straight through as it would had it no mass.. Bending light is easy, you just need to slow it a bit .. right? 😉
” and not because light had mass”
Far be it for me to disagree, but that isn’t why light is bent, actually light isn’t bent, the light goes straight, it’s space time that’s bent.
Or so it is said by Einstein.
What is cool, is that we now know we can observe/detect these events and when the third observatory in Italy starts up near the end of the year, we will be able to triangulate the exact position of where the events occurred. And then put other space observing platforms on them.
Large supernova impacts and neutron star interactions will be the next targets. Black holes probably merge several times per year within a few billion light years, but there will be dozens of these other events each year within several hundred million light years.
A new window on the universe has opened and it has the most amazing events in the universe in its looking glass.
I also like the fact that there really are black holes in space because nothing else could cause these type of events. And that fact that whole stellar masses are converted into energy within milliseconds. Our Sun will take 8 billion years to emit/lose 3.0% of its mass. We have events here where 100 times as much mass is converted into energy within milliseconds rather than 8 billion years. Someday, we will find a way to make use of the energy that this represents.
Ligo a funding black hole joke.
Dark Matter: naming the unknown doesn’t explain it but serves well as the last refuge for the willfully ignorant textbook thumpers.
Internet: Serves well as last refuge for the willfully ignorant layman who thinks someone may care what they think and they matter to the world.
Who is this someone though?
Einstein would have been one of those “internet theories” had it been around in his day, Neils Bohr, Newton, Tesla, and Darwin and god knows who else would have started out with sharing their ideas online and disagreeing with dogma.
Many of the fantastic claims in astronomy just dont stand up to basic questioning.
LdB:
By using the term “layman” you firmly establish that “science,” in your perception, is no more than some form of a religious dogma or of a bureacratic hierarchy where hollow paper credentials mean more than trying to understand the reality.
As you can see in the posts following your tasteless attempt to silence the dissent, there are many people who care about what I think about, or at least many people who think in similar ways.
We do not have a plausible explanation of the phenomenae that are being arbitrarily called “dark matter” and “dark energy.” It is quite possible that modern cosmology is wrong in some fundamental respects. It is quite possible that Narlikar and Arp (whom even orthodox academic automatons wouldn’t dare calling “laymen”) are right, and that there is a relationship between mass and time that would explain the observable Universe in much simpler and substatiated ways than those proposed by the defenders of the creationist status quo.
In short, I think on my own, and express my opinions. Yes, Internet defeats your attempts to silence the dissent. Good.
LdB says:
“Einstein, Neils Bohr, Newton, Darwin all got engineering or science diplomas/degrees and published papers.”
That made me laugh out loud. You really don’t understand, how stupid is what you wrote?
LdB says:
“Tesla complete a university engineering degree but did not sit the final exam and he did publish several informal papers with enough detail for us to at least understand his theory.”
That clinches it. You admonisg others while having no clue. Nobody understands most of the Tesla’s theories (Tesla had no single “theory” of anything). At least try to find a good biography of Tesla, and read it. How ignorant can you be? Amazing!
Dark Matter was concocted purely from thin air, literally, to make the calculations work.
Finite speed is also needed to make the calculations work, and some foolishly believe this means the universe requires this finite speed.
Special relativity does not know what acceleration is, General relativity doesn’t know what force is.
Some people cannot understand the implications of this. People with PhDs too, scary
Many of the fantastic claims on the internet just don’t stand up to basic questioning.
Einstein, Neils Bohr, Newton, Darwin all got engineering or science diplomas/degrees and published papers. Tesla complete a university engineering degree but did not sit the final exam and he did publish several informal papers with enough detail for us to at least understand his theory.
So what is Mark-Helsinki’s education background so that we could have some confidence he actually has a clue what he is talking about. Published any papers we can reference?
you.. you’re requesting someone reply to your appeal to authority?