From the AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE
Science has chosen as its 2017 Breakthrough of the Year the first observations of a neutron-star merger, a violent celestial event that transfixed physicists and astronomers. As the two neutron stars spiraled together 130 million light years away, they generated tiny ripples in the fabric of spacetime called gravitational waves, sensed by enormous gravitational wave detectors on Earth. This merger also triggered an explosion studied by hundreds of astronomers around the world. Researchers first picked up on gravitational waves over two years ago, when two massive black holes crashed into each other.
This space tremor was detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO), a discovery that landed Science‘s Breakthrough of the Year for 2016 and won the 2017 Nobel Prize in Physics. The discovery showed that gravitational waves offer a new way of observing the universe and a major tool for astronomers. “Gravitational waves are the gift that keeps on giving,” explains News Editor Tim Appenzeller.
“Observers not only detected gravitational waves from a collision of two neutron stars; they also saw the event at all wavelengths of light, from gamma rays all the way to radio. Being able to get the full picture of violent events like this promises to transform astrophysics, and that made this year’s observation the clear Breakthrough for 2017.”
On 17 August, gamma-ray detectors and radio telescopes sensed the merging of neutron stars. Because the ripples were spotted by three widely spaced detectors, scientists acted quickly and triangulated on the pair’s location in the sky.
“Within just 11 hours, several teams had pinpointed a new source on the edge of the galaxy NGC4993. The explosion was easily the most-studied event in the history of astronomy: Some 4,156 researchers from 953 institutions collaborated on a single paper summarizing the merger and its aftermath,” says Science staff writer Adrian Cho. He further notes, “Astrophysicists say the neutron-star merger only whets their appetite for more data.”
Plans are already underway to improve LIGO’s sensitivity at higher frequencies. Scientists will begin such efforts by manipulating the laser light circulating in the detectors, though such an endeavor might take a few years.
###
Fascinating. It will be nteresting to see more of the corroborating data.
Depending on ones understanding of science and scientific proof, a model that predicts data with many sigmas’s of precision is perfect statistical proof. The conspiracy of ignorance masquerades as common sense.
Sadly, LIGO’s inconsistencies make it more of a fake news, and a money burning scheme. There is a discussion going on about it on RG, and it is not going well for the LIGO.
What is “RG”?
I’m still sceptical about LIGO. When I first read that they’re “measuring” an expansion/contraction that is a fraction of the width of a proton, I thought there is NO possible way that they could measure a distance that small – using 4km long lasers. Natural background noise would overwhelm the data by many orders of magnitude. And as it turns out – they don’t measure it. What they do is use COMPUTER MODELS to filter out the noise and presto, the data they want appears.
Maybe they really have achieved it, but when ever I read that people are using computer models to give the data they are looking for, I become sceptical.
Gimme a break. This is not a Parmesan.
So can you make an actual argument based on knowledge of the issue ? Or do you just rely on ad-hominem abuse ?
I was skeptical also but, as the mentioned, “they also saw the event at all wavelengths of light, from gamma rays all the way to radio”. In other words, there was independent verification of the event based on the detection by LIGO. Oh, and not one but two interferometers detected the event and they were able to give a general direction based on that. Two having a false signal at the same time coupled with the ability to independently detect the event by other means certainly gives a lot of credence to them working.
It was seen by 3 detectors VIRGO in Italy was online. The optical and radio telescopes would also never have seen the event without LIGO first triangulating it and the refinement of the direction was only because they had 3 detectors. The event only lasted days and you had to be looking at that area of sky a needle in a haystack thing without the GW detectors. All 3 are back in operation from Nov 30 and so early in new year there will be new detections because they are fairly common.
Yeah, having the event visible on whatever frequencies that could be detected is quite strong affirmation that something was happening. If it was an artifact of one instrument, then the other unrelated instruments would not be detecting anything.
Bear, I have been taught that gravity is an instantaneous thing, if they detected something at the same time as all the light frequencies something is amiss. Either their theories on gravity are wrong or they detected something else?
GR has always predicted that gravity propagates at c, while Newtonian mechanics typically treat it as instantaneous. Since Newtonian math is usually good enough for satellites in Earth orbit or space craft in our solar system, we usually go w/those in day to day applications. For one thing, the math is WAY easier, for another the precision gained is usually — but not always! — swamped by perturbations from other objects/phenomena.
That said, many experiments have been done which seem to show that gravity/gravitational waves do propagate at a finite speed, c. Among these are the difference in position of oceanic tides on Earth vs the position of the Sun (solar perspective vs geocentric) & the bending of light from distant stars past Jupiter (when we see it vs when we expect to see it). The most famous example, perhaps, is that of the precession of Mercury’s orbit: predictions done using Newtonian mechanics eventually diverge from observation by a significant amount… so much so that it was noted back in the mid-1800s; GR, using a light-speed propagation of space-time deformation to explain gravitational effects, is accurate to within the margin of error for observation even using today’s instruments.
My knowledge of physics is not very good, but I think you are going by Newton, not Einstein.
ggm, I understand your skepticism about computer models. But they are only a tool. If someone tries to use a hammer to saw wood you can say that they used the tool badly. Not that it is a bad tool.
Factually we use models all the time, and you couldn’t get very far in life without them. When you are driving, don’t you look at the gas gauge? Failing to look at the gas gauge ends badly. But you are using a simple model every time you do it – a 16 gallon tank, gauge shows 1/4 full so I have 4 gallons left, at roughly 20 miles per gallon I can only drive 80 more miles. Better not get on that freeway that has the sign “NO GAS FOR NEXT 100 MILES”.
Of course this simple model has all kinds of flaws. Gas gauges are notoriously inaccurate. Mine shows “empty” when there are still about 5 gallons in the tank. You don’t really know if you get 20 miles per gallon on the gas that is in your tank. If it is contaminated with ethanol you will get less, if you drive fast or hit tons of stop lights you will get less. If you are wise you won’t trust it much beyond the simple observation that it is getting low and you’d better get gas soon.
But it is still a model and it still uses computation (even if you are using a gray matter computer). It still follows the basic laws. You have a physical “law” which is more or less established (gallons of gas times MPG equals miles travelled). You also have tons of parametrizations. These are what we used to call “simplifying assumptions”. You assume a fixed number for MPG when it is really changing every time you change how you drive, the temperature, the type of gas, altitude and so on. You assume the gas gauge is accurate or you may know corrections that make it more accurate (EMPTY means 5 gallons left). Despite all these sloppy inaccurate features you can use it to make valid decisions. You just have to factor in a large error band and err on the safe side.
I use models all the time at work, doing design engineering of electronic equipment. You use models all the time. If a model is being used, it is vital to know how much of the model is parametrized and how much is truly based on basic physical principles. You have to know the error bands on the data that is going into the model and the error bands of error sources in the model.
This is where the IPCC CMIP5 models break down. So many of the important details are buried in proprietary code or hidden by the complexity of the model. And so many parametrizing assumptions are made. There are examples of circular reasoning. They have to average model runs with slightly altered assumptions and use many models, a strong indicator of a weak tool. They are poor at hind-casting and their forecasting tends to blow up into catastrophic warming no matter where they start or what assumptions they use.
It is just as bad as using a screwdriver to open a tin can. But that doesn’t mean screwdrivers are bad.
Screwdriver to open a tin can. Great analogy!
Not to be facetious because I accept your point generally, but maybe your car stops with 5 gallons of fuel remaining. If the pick up tube is bent upward?
The problem with models is when they stop being tools and become solutions. And what sort of tools are they, anyway? They should be used to guide investigation, not to provide answers. Their use in climatology has been as a substitute for science. If astrophysics operated like climate science they wouldn’t have looked for the object with optical telescopes for fear of proving themselves wrong.
By the way, I once owned a Dodge Shadow that seemed to run out of gas at an 1/8 of a tank. But then it started up again an hour later. Long story short I eventually figured out that the fuel got too hot from recirculating through the fuel pump in hot weather with the tank level low and caused it to vaporize or cavitate (can’t say which, the science isn’t “settled”) .
My model was correct, my assumptions about what other factors might mimic the observations coloured my interpretation of the model result. Thank goodness climate is much simpler than a car engine./sarc. Also , my career wasn’t on the line if I dealt with the problem truthfully.
Excellent analogy. I have a Ford Windstar that was top of the line – 15 years ago. One of its features is a digital readout that says how many miles until empty.
Last week, it was disconnected from the battery for a few days while I tracked down the right replacement relay for it. When I got it back up, it was using the “factory new” figure for MPG – about 21 miles per gallon. Regathering its experience in our actual driving (mostly city), it went back down to the 17 MPG that is normal for it. (The engineers obviously knew what they were doing, too – get below 50 miles left and it starts dinging you about low fuel – they realized it was not going to be accurate right down to even 10 miles left.)
LIGO does much the same thing – they constantly monitor the noise in the system, and use that data to model what it probably is at any one specific time, when they do have a real signal. A good music system does exactly the same thing with a FFT (Fast Fourier Transform).
GGM, the small spacetime distortion is observable because LIGO works by interferometry over a very long distance. The coherent spit laser light has several kilometers of spacetime out and back over which to become slightly out of phase. The slight incoherence in the recombined 1064 nm laser beam IS the gravity wave signal.
The computer processing filters out things like mirror mechanical vibration that could also cause incoherence by varying path lengths along the two perpendicular arms.
There are very interesting papers about the long history of LIGO and how it has become adequately sensitive.
coherent spit… LOL . Some typos are funny.
Never saw it. But it is sort of funny.
When the causality arrow of detection runs in the direction of new detection system => old detection system, you have achieved something useful and real, despite misgivings about models.
BTW, as I’m fond of talking about your stereo system – it’s based on models. All engineering is models, all the way down. They happen to be models that work very consistently.
I can’t remember who came up with this but it’s a good quip – it’s not confirmed science until someone engineers a useful product with it.
In this case, the LIGO folks have engineered a method of finding neutron star collisions that allows the old fashioned telescopes to find the needle in a haystack and observe the same occurrence that they normally would never see. That’s about as confirmed as it gets.
I now believe LIGO is real and effective. I used to be skeptical.
Peter
The models only help tune the filters, they don’t produce the signal. If the models are wrong, the detector either produces lots of false positives – in which case the odds of three agreeing simultaneously is nearly nil, or they don’t produce anything at all.
The data track shows a signal is barely above noise. I am skeptical but open to better data.
You guys are up early this festive weekend.
Thanks for all your hard work.
Merry Christmas to all.
Merry Christmas to you also. If to all WUWT folk.
Up this early all the time.
I’m up most lunchtimes, here in SW France I think it is normal 🙂
SteveT
Not what I heard. And I heard it on the internet.
If the explosion was caused by two black holes (black because no light can leave) how did all that light from the explosion get here?
There was some stuff outside the holes.
Actually, the news is about neutron stars, not black holes. But active black holes do throw hot stuff and radiation around, if you manage to look at the direction at the right time.
Only stuff outside the event horizon. But this was a colision of two neutron stars, so there was no event horizon until the resulting ‘small’ black hole formed, if one did (depends on how much mass was ejected). Hence the multiple observations across the electromagnetic light spectrum.
The article called the event neutron stars colliding twice and black holes colliding one – it was caught in the confusion as well. I am pretty sure it is neutron stars.
The black holes were an early event. This time with the neutron stars they were able to get independent visual confirmation.
What I find interesting about that is the light from this merger that happened in a whole other galaxy reached us at the same time as the gravity waves. This effectively confirms that gravity waves propagate at light speed. That invalidates quite a few theories.
Honor Harrington is going to need something else for FTL communication.
^¿^
No confusion. There have been 4 black hole and one neutron detection. Black hole chirps last a couple of seconds. The neutron chirp lasted about 100 seconds. That plus the EM frequency observations both prove it was a binary neutron star collision.
@schitzree – Preempting David here (assuming he even lurks on WUWT), what Honor uses is the propagation of gravity waves through hyperspace, where “c” has a much higher value.
Handwavium is a fine art. One where few SF authors even manage the skill exhibited by quantum physicists. (See the Wheeler hypothesis that our observation of events now propagated back in time to create the Big Bang…)
schitzree
December 23, 2017 at 6:48 am
– ” What I find interesting about that is the light from this merger that happened in a whole other galaxy reached us at the same time as the gravity waves.”
No, actually the gravitational waves did propagae at the speed of light and they actually arrived well before the electromagnetic radiation…gamma rays 1.7 seconds later (after travelling 130million light years), visible light 8-9 hours later (thus allowing time for optical telescopes to watch it happening), UV, X-rays, radio, etc. also later. To me that’s the interesting bit…only the gravitaional waves travelled exactly at the speed of light…nothing to interfere with them as they are only distorting spacetime. The EM waves interact (albeit only slightly) with other stuff on the way or at the merger site. At least that’s my understanding as an astronomy amateur.
Everyone knows that tachyons travel FTL. Models tell us so. Coincidentally, I am reading all about them right now in Benford’s Timescape.
So the breakthrough of the year wasn’t proving a link between CO&#;8322 and cagw. Michael Mann will be gutted.
Darn being lazy with my CO₂
Maybe I’m a bit ignorant here, but I’m confused. The title mentions the merger of two neutron stars, but the first paragraph talks about the merger of two black holes. So which is it? I was under the impression that neutron stars are not the same as black holes.
Never mind. I read the paragraph again for the third time, and I had misinterpreted the last statement. Apologies for my ignorance. 🙂
I’m sure it’s an interesting set of observations for the physicists involved, but I don’t see why it is described as the “breakthrough” of the year. The instruments were already up and running, and the article describes the use of gravitational waves over two years ago when the black holes were observed to collide.
The collision of the 2 black holes proved that LIGO was working and that they could detect gravity waves. Two years later (recently) they were able to observe a different collision – this time of 2 neutron stars. And this time they were able to observe the collision by > 4,000 scientists at 953 institutes from all over the world AND observe it at every single wavelength and type of detector we have developed over the last decades! They can plug this observational data back into their mathematical models to improve the models and perhaps will see new and unexpected things once the data is fully analyzed. This data may also shed light on long-standing debates within physics and astronomy about the gravitational constant and dark matter/energy – who knows – that is the purpose of collecting new data. No, I am not a physicist or astronomer (actually a biophysical chemist) but I did sleep at a Holiday Inn Express last night. 🙂
One of the results is to identify that neutron star collisions produce heaver elements.
https://www.sciencefriday.com/segments/a-stellar-collision-ripples-in-space-time-and-the-origins-of-gold/
There was negligibly small chance you would have seen the event without LIGO you would have had to have a telescope targetted at that section of space for what was a couple days in the billion years of history of that section of space. The fact you could get such a specific warning of a unique event and target 70 other telescopes at the event made it the obvious choice of breakthrough of the year. Scientists now have data they would never have had without the GW detectors.
the gamma ray burst was independently detected and optical telescopes would have still studied it and recorded the light decay curves.
The ability to detect gravitational waves represents a new and powerful tool for astronomy generally.
Some details here https://www.scientificamerican.com/article/the-future-of-gravitational-wave-astronomy/
LO<Lcomments. But what do you expect from a bunch of skeptics!
LOL, comments. But what do you expect from a bunch of skeptics!
Granit……..you prefer humans that always accept that which is offered; your journey following the Pied Piper needs a Red Pill.
Go back and re-read the newer comments. Self-correcting to a degree – like science.
This thread is exactly what I expect from a bunch of skeptics. It’s a beautiful thing, and I’m probably not the only one learning from it.
Agreed. We all learn, and sometimes we can contribute snippets from our own specialised areas. Except ristvan, of course, he has no specialised area because he knows everything (well, nearly everything). No offence intended; polymaths are valuable assets and we’re lucky to have one of our own.
electrician exactly! geologist/mining engineer here, happy to be learning this beautiful stuff from the world’s smartest and most generous people. I believe that here at Wuwt university my knowledge of climate now surpasses that of most mainstream climate scientists, and I never got started until i was in my 70s.
It’s a breakthrough because their new ability to detect and measure gravitational waves is allowing them to find and pinpoint and study some rare events in the universe that we can learn from. In this case the collision was studied “as it happened” rather than after-the-fact and lots of useful data was gathered. But in the future who knows what it will lead to?
“As it happened”. It may be just me, but I have a hard time wrapping my head around that. So I guess gravitational waves travel at the speed of light?
That is the theory. General Relativity predicts it should travel at light speed.
In Astronomy, “As it happened” means millions of years after it happened but when the perceivable effects reach the Earth. You just have to know the lingo…
Not just theory measured by between the 3 detectors for the detections current measurement at 299,792,458 metres per second
Given that the LIGOs have only been operational for a few years, its is more likely they are not so rare. There’s enough galaxies within 100Mparsec to push a 1E-07 events/galaxy/year probability to see one every few years.
Try every 2-3months and they have increased the sensitivity and the detectors have been running again since 30 November so expect new detections in new year.
Telecomms merge. Stars collide.
Once in a while a vehicle fails to merge correctly on the freeway and a collision ensues. Merge is kind of a poor term for a violent celestial concurrence, unless speaking of merging galaxies, which will also cause collisions in the process.
Actually, I heard somewhere – Carl Sagan? – that merging galaxies produce no collisions, as distances between stars in a galaxy are so vast.
Closest star to our sun is over 23,000,000,000,000 miles away.
Vehicles don’t fail to merge properly, drivers do.
Reminds me of another terminology curiosity.
When Parachutists hop out of an airplane they call it a jump, unless the chute fails and then it becomes a fall.
And pilots ask why anyone would jump out of a perfectly good airplane.
Black hole do actually merge – to form a single bigger black hole. The remnant of a neutron star collision may also result in a single black hole … as proposed for the collision that was observed.
Steve T – anywhere near St Cyprien?
Thank you Anthony and all contributors to WUWT. I have learnt so much over the years reading here. A happy Christmas to all and the very best for 2018.
And a Merry Christmas to you!
So wonderful to see settled science -at least as much as science can be-. We “saw” two neutron stars merge, according to the best of our tools and models, and even the consensus of our hard scientists. I can go with that. I can’t wait for the next 100/1000 years of this….. If only I had that many years. Can’t we please take all the money shoved down the global warming -wannabe- hole and task it to discover things like this.
Forget about consensus. Look at the epistemological situation. Read your Popper and then look at the evidence.
You don’t need to be a math or science guru to understand that if you can locate a celestial event with the new method and the old method, the new method is effective.
I have yet to see the “consensus” in sociological and climate sciences be able to predict their large complex systems to any degree of accuracy at all. A decent epistemological expert (e.g. Taleb) would tell you why, both from a common sense and mathematical standpoint.
Or you can go with the old standby – until some scientific idea is used to engineer a useful product, it’s probably not confirmed science. You don’t have to be a philosopher or scientist to make that kind of judgement.
Peter
Didn’t Willis put forward a theory that the validity of an article is inversely proportional to the number of authors? 4,156 authors if anyone who did significant analysis get a credit? That must set some sort of record.
(only partially being sarcastic – it seems like this would have been better as perhaps 40 or 50 papers about the individual analysis projects for each sensor pathway (still 100+ authors each!) and a good summary paper using all those as references.)
That is true in climate science, but not true concerning particle physics (CERN) or astrophysics as here.
Too bad we cannot get 535 Members of Congress to agree on anything.
I’ve wondered if the Sun felt the shaking. Its big enough to be a LIGO.
It’s not shaking its a space distortion and there is nothing about the sun that would function as a LIGO.The most common emitter of gravity waves is two bodies revolving in orbit about each. The earth-moon revolution is the strongest emission of gravity waves local to earth along with the tidal shift and LIGO has to filter them out. The Sun-Earth because of the distances and slower speed emits lower level gravity waves and much slower.
Since gravity waves are now confirmed you can consider it like resistance of space and all space orbitals are decaying as they are losing energy just very very slow via the gravity waves.
Hannes Alfvén might have an opinion if he were around today. The sun has strong Magnetic field lines thousands of miles long embedded in hot plasma. The structure of the deeper field lines may be more laminar. unlike those near the surface that become turbulent and chaotic. If that were the case it might take some weeks for the disturbance to reach the surface/photosphere.
Would not “two bodies revolving in orbit about each other” have a fairly stable centre of gravity? And their collision would not move this COG appreciably? Is it not possible that powerful gravitational events affect all mass in the Universe instantaneously, while a relatively slow “aftershock” travelling through the recently re-hypothesized ether at light speed could be measured by distant detectors millions of years later? Maybe we can have our cake and eat it too.
The other interesting aspect of being able to observe the light emitted by the merger of these two neutron stars is that the light contained the signature of many heavy elements.
The merger of neutron stars is a significant source of the heavy elements beyond iron/nickel. Supernova explosions also create these elements but neutron star mergers are also a significant source.
One can imagine two stars made-up mostly of neutrons held together by massive gravity (gravitational velocity is half of the speed of light at the surface of a neutron star). As they merge, material gets spun out and escapes the gravity. Instantly, unbelievable numbers of neutrons split into protons and electrons and unbelievable numbers of neutrons remain as a well.
The speed of this material at somewhere around half the speed of light or more is crashing into each other fusing neutrons and protons into giant atoms. The majority are highly radioactive and break apart in a millisecond, but what remains is the stable giant atoms/elements and the isotopes of those atoms/elements that can last for more than a millisecond. The majority of the isotopes are not stable in the long-run and eventually split apart until only the stable elements and isotopes remain, flying away at tremendous speeds..
These very large atoms and isotopes will contain some amount of uranium, platinum, gold and other heavy elements so this is one source for where the elements heavier than iron/nickel come from.
While some amount of material gets spun out in the merger, what is left behind is most likely a black hole. Neutron stars only have masses between 1.5 solar masses and about 3.0 solar masses. After 3.0 solar masses, gravity becomes so strong that it becomes a black hole. So, put two neutron stars together and the mass likely exceed the black hole limit.
So the merger created lots of heavy elements flying away at tremendous speed and a black hole. There are more than 1 billion neutron stars in the galaxy and lots of them have merged together in the past 12 billion years which means the galaxy has lots of heavy elements and lots of black holes.
Good info. The original cloud that formed our solar system must have had remnants of neutron-star collisions.
Actually, all elements beyond iron are not produced by main sequnce fusion. They are produced by supernova or by neutron star merger. And now we know that neutron star merger preferentially produces more very heavy (protons in neucleus) elements.
Bill, would this have created a burst of cosmic rays as some atoms are stripped of their electrons during ejection?
“Supernova explosions also create these elements but neutron star mergers are also a significant source.”
Supernovae create a surprisingly small number of the heavier elements. (see the white dwarf contributions on
https://upload.wikimedia.org/wikipedia/commons/3/31/Nucleosynthesis_periodic_table.svg)
Most heavier elements require explosions with more punch. Also interesting that boron and beryllium can not be produced by stellar nucleosynthesis – they are fission products of cosmic ray bombardment.
What if…. upon receiving our radio and TV transmissions… an alien civilization simply interprets them as cosmological phenomena? In order to prove this they would be compelled to build a ludicrously intricate model of spinning ferric objects careening around and off of each other. To speed it all up, maybe a clockwork of black holes and plasma tubes and quantum donuts of various sizes dancing in three dimensions cyclic on the pattern of some Golay Perfect Code so that it may provide a base carrier wave for aeonaeons, with various masses modulating the signal.
With some parabolic Dysonish reflector around it, that just happens to be focused in the direction of the alien civilization. As the waves come off the parabola the three dimensional model the waves combine to form the precise EM wave that matches the signal they received. Years of radio and TV transmissions. It’s a very complicated model but the aliens are meticulous and patient.
And perhaps… they manage to do this, but limitations of physics only permits them to build a slow moving model. It would (amazingly!) generate the proper waveform of the voices and music they ‘hear’ but do not perceive… explaining the nature of the wave completely. But they cannot make their model ‘work’ at the speed necessary to explain the high frequency waves they received.
So, in the end… to explain the high frequency… the aliens would be forced to conclude that this ponderously complex cosmological juggernaut was all traveling, at high and uniform velocity, directly towards them. It would raise a panic.
I can imagine them in a high state of anxiety, waving their pseudopods around.
Yeah, and if I ever finish my book about being kidnapped by aliens I will be a thousandaire.
Careful Hocus, someone may take this and run with it. It’s scarier than a fraction of a degree of warming per century and it would cost quadrillions to build a model to protect us from the coming invasion. Only lefties would buy into it but don’t forget a thoroughly corrupted broad got the majority vote (sorry, is this a legitimate diversity category? Being in the demographic that isn’t accepted into the diversity klatch, I haven’t had cause to sort it all out). Anyway, my point is that the majority of people have been moronized by substitution of independent thought by mindless talking points and Alinsky’s Rules.
https://www.steelonsteel.com/saul-alinskys-12-rules-for-radicals/
Read this link! You’ll thoroughly understand and recognize what we are up against.
As soon as they tuned into the 1950’s original I Love Lucy and the The Honeymooners broadcasts, they’d have known there was NO intelligent life here and they would’ve moved on. We were saved from alien colonization and extinction. Whew!! Dodged a bullet we did.
There’s GOLD in them thar collidin’ neutron stars. GOLD I tells ya. /crazy forty-niner mode
Half a planet’s worth, from one estimate based on the gold emission spectra.
Wonderful event, we’ll learn a lot from it and future ones.
Exciting stuff. Too bad there isn’t a way to get to watch the event before the aftermath. Do the gravity waves only develop at the point of collision or are their very low frequency waves generated in advance. It would seem logically, that as the bodies approached, you would begin to get perturbations that would generate gravity waves unless it happens with the massive destruction of matter on collision. Is this stuff too new to know about?
Read up on this at the time of the first black hole detection. We are limited by LIGO sensitivity. So it is only as the two objects orbiting each other get very close at a very high spin rate (figure skater spin analogy, just conservation of momentum) that we can detect the gravity waves produced.
It is only in the last several seconds before merger that the wave amplitudes are strong enough detect at megaparsec distances. So time-wise, the gravity waves arrived at LIGO, then a second or so later (when the physical merger occurred) the GRB flash arrived at Earth. A one-two punch. Then the optical guys get alerted and start hunting it down to record the light decay curves.
Maybe Granit from upthread can answer your questions Gary, since Granit finds us so comically naive…
Science is based on measurements and observations; neither of two are exact, but are only approximations of the reality, thus as such are likely to be wrong in some extent.
Knowing the extent of ‘how much wrong’ is the essence and beauty of the good science.
From the original report at physicsworld.com:
“The gravitational-wave signals were measured for about 100 s, whereas those from previous black-hole mergers lasted less than about 1.5 s. This longer measurement time reduced the uncertainty in the location of the merger, while the shape of the signal allowed astronomers to estimate the masses of the neutron stars to be about 1.1 to 1.6 solar masses. The amplitude of the signal gives the distance to the source to within a 30% margin of error.
High-energy gamma rays from GW170817 were detected in the form of a short burst, some 2 s after the gravitational waves. Astronomers had suspected that such bursts are caused by neutron-star mergers, but had little understanding of how it happens. “We confirmed that colliding neutron stars power short gamma-ray bursts, solving one of the greatest mysteries in present-day high-energy astrophysics,” says Francesco Pannarale of the University of Cardiff in the UK.
The prompt arrival of the gamma-ray signal also confirms that gravitational waves travel at the speed of light, while the ability to observe light and gravitational waves arriving from distant objects will allow physicists to perform more stringent tests of Einstein’s general theory of relativity.”
Nice to see that Kenji shares his materials with Anthony. Happy holidays to all.
Happy pre-holidays everyone…:)
Sorry lads, boyz and girlz, but this is ‘a bit poor’ Must try harder.
Are there 100 billion stars in our galaxy?
Stars last how long? Maybe 10 billion years then go (supernova) bang.
So we get 10 bangs per year in our galaxy
Now, get a 10 pence piece (is a dime about the same size) and hold it at arms length up at the sky so it blots out a circular piece of sky. Any direction you like.
There are 100,000 galaxies behind that dime.
Thence 1 million supernovae, annually, behind the dime. 100 per day?
(Maybe devise a ‘holding contraption’ for the dime – gonna get crippling arm-ache otherwise. Jam it in a tree or something.)
S’pose we’re left wondering how many supernova leave neutrons behind and how many are close enough or get the inclination to merge but, something tells me that, across the whole sky, it’s gonna be more than one every 2 years……….
Pete, quite right, but Mother Nature does not respect your calculations.
Here’s a link to the LIGO event fact sheet:
http://www.ligo.caltech.edu/system/avm_image_sqls/binaries/99/original/GW170817_Factsheet.jpg?1508114118
Whether neutron stars or black hole candidates, the signals detected by LIGO occur at the orbital frequencies of two massive, compact objects as they circle their common center of mass. As they lose energy via gravitational radiation, the orbital period shortens. This produces a “chirp” signal at increasing frequency until the objects merge. Neutron star pairs orbit more rapidly and produce higher frequency gravitational waves than the more massive black hole candidates. So far there is nothing other than the larger masses to indicate that any of the objects might be black holes; i.e., there is as yet no evidence for the existence of event horizons. The designation of an object as a black hole candidate is presently based solely on the presence of a mass in excess of three times that of the sun. That is the limit calculated for neutron stars using general relativity. Eventually there should be some mergers detected for a neutron star and a black hole candidate. That might reveal some differences that would tell us whether event horizons exist. I would offer a wager that they do not.
I will wager that event horizons do exist, because the math of general relativity says so and the theory has been validated in so many other ways.
I hate to disagree with someone whose comments are so often correct, but there has never been any published confirmation of an event horizon in any observations. They are artifacts of a flawed interpretation of general relativity. Although attributed to Karl Schwarzschild’s 1916 solution of the general relativity equations for a point mass source, his solution did not actually predict the occurrence of the event horizon. It is still a perfectly acceptable solution without the excess baggage of an event horizon.
An event horizon is a singularity in space, at which the gravitational force on a test particle would become infinite. There is neither a curvature singularity nor any mass at that location. Recent work by Hawking and others have shown that such a singularity is incompatible with quantum field theory. I do not believe that singularities exist within physics. When found within theories they always involve a failure to understand some essential feature of the problem.
Among the things remaining to be understood are the compact objects that are called black holes without any proof of the existence of an event horizon. They are certainly massive, compact and dark, but that is merely a consequence of having gravitational redshifts so large that they emit almost no detectable radiation. The brightness of quasars and x-ray novae arises from exterior accretion disks.
Although general relativity is the most widely accepted theory of gravity, it is not lacking for rivals that explain all of the same observations that support it. It was merely the first to get many things right, but it will not likely be the final word on gravity theory. General relativity encompasses a very meager list of phenomena compared to quantum theory. It has been tested far less severely and yet remains incompatible with quantum theory. One or both of these currently dominant theories will need to be changed. My bet is that the much more extensively and severely tested quantum mechanics will survive, but general relativity in its current form will not.
>>
I hate to disagree with someone whose comments are so often correct, but there has never been any published confirmation of an event horizon in any observations. They are artifacts of a flawed interpretation of general relativity.
<<
You can get an event horizon using Newton. The formula for escape velocity from the surface of a body is:
(simple Newton derivation). If we set 
, the speed-of-light, and solve for r we get: 
. The event horizon is where the escape velocity is equal to the speed-of-light.
There’s a star, S2, that is orbiting a central mass in our galaxy in 15.2 years. From the orbit, S2 is orbiting an object equivalent to 4.1 million solar masses. S2’s closest approach (periapsis) is about 17 light-hours. 17 light-hours is about the orbit size of Uranus. There’s no way that S2 can orbit a 4.1 million solar mass object and it not be as small as the Schwarzschild radius.
If it’s not an event horizon we are observing, then you’ll need to invent some new physics to explain it away.
Jim
Come on man.
1. What is or is not a Breakthrough?
This is a breakthrough if one changes the definition of breakthrough.
A breakthrough is something that changes civilization, some that has real implications, something that fundamentally changes our understanding of the physical world.
A check mark for the standard physics theories/models is not a breakthrough.
Quantum mechanics was a breakthrough.
Almost every electronic device which we use, most of our advanced technology – is directly or indirectly – possible due to the quantum mechanics phenomena and the application of the quantum mechanics model. That’s a breakthrough.
2. Gravity Wave Detection
The detection of gravity waves has been predicted for 30 years.
Gravity waves are not new.
We have known for 30 years that the orbiting period of binary pulsars slow – it was assumed by emitting gravity waves – with slowing in period being in accordance to the applicable standard model (general relativity) calculations within 0.2% of what General Relativity predicts.
https://arxiv.org/pdf/astro-ph/0407149.pdf
3. Why the heck has there been no real breakthrough in Physics?
There has been no breakthrough in physics, for 30 years.
See:
The Trouble With Physics: The Rise of String Theory, The Fall of a Science, and What Comes Next
by Lee Smolin
https://www.amazon.com/Trouble-Physics-String-Theory-Science/dp/061891868X
A scientific breakthrough is being able to do something in science that hasn’t been done before, William. If you’d check the discipline in which the award was given (science), this would certainly qualify.
A signal. One day, when we reach beyond the solar system, its characterization may be confirmed or rejected.
“The prompt arrival of the gamma-ray signal also confirms that gravitational waves travel at the speed of light, while the ability to observe light and gravitational waves arriving from distant objects will allow physicists to perform more stringent tests of Einstein’s general theory of relativity.”
Hmm…
Einstein’s theory of relativity states when velocity increases the time slows down.
If “the gamma-ray signal also confirms that gravitational waves travel at the speed of light” the time for the gravitational waves slows down to ‘zero’, i.e. the time stands still, i.e. there is no time.
The universe is meant to be a spacetime continuum, spacetime is a mathematical model whereby the three dimensions of space and the one dimension of time are merged into a single four dimensional continuum.
I’d like to know if there is no time (as far as the gravitational wave is concerned) what happens to the ‘spacetime’ thing.
I’m also a bit puzzled about the effects of gravitational waves travelling at SoL.
My issue comes from the failure to detect the Higgs – although the hype was remarkable, the fact is SUSY and Multiverse models postulated 2 very different energy levels. IIRC it was 140 GeV and 115 GeV. The ‘findings’ of the 2 experiments invalidates BOTH models at 126 GeV.
Also confusing is Einstein’s ‘dimples’ in spacetime causing gravitational effects – if the SoG = SoL then we have a situation where the dimple is causing an effect after the mass has moved on.
e.g. The Sun orbits the barycenter and the Earth orbits CoG of Earth-Luna. At a given instant the Earth is at point A in its orbit, and the Sun is at point B but when the gravity ‘arrives’ at earth, it is 8.3 minutes later so the attraction is to a point that is no longer where the Sun is centered.
With the Higgs issue, how does gravity get transferred from a place where it isn’t? And reach a place where there was nothing at the time of origin?
If the Higgs is valid, the information contained is incorrect for the system in time A+8.3 when it arrives because gravity is 2-way. i.e. the Earth is pulling on the Sun just as the Sun pulls on the Earth, but when the gravity arrives the information is for a time 8.3 minutes prior to ‘now.’
Your problem is that you are shifting your frame of reference. Either your frame is centered on Earth, or it is centered on the Sun. Switching between the two causes you to think there is an 8.3 minute difference when in fact there is none.
@C. Paul Pierett – “Your problem is that you are shifting your frame of reference. Either your frame is centered on Earth, or it is centered on the Sun.”
Maybe I am not explaining it well, but I don’t think that’s the case.
From earth reference, the Higgs arriving ‘now’ is coming from a point in space 8.3 minutes ago – the Solar centre of mass is not there now and the information in the Higgs is based on a point 8.3 minutes back in Earth orbit.
It seems to me, in such a case, the Earth would be continually slowed down by being influenced by gravity back along its own track.
For it NOT to be, wouldn’t the Higgs have to update its information store along the path from Sun to Earth? And it’s a 2-way interaction, making things even more confusing.
It may mean that as the velocity of a mass approaches an upper limit, time (or motion) becomes irresolvable or imperceptible for observers inside the system (e.g. universe). The implication is that time is not a separate dimension, but rather a property of kinetic energy. So, time does not exist in a perfect stasis, or in a frame of reference where the processes are undifferentiable.
If I were a gravitational wave (which I’m not) there is no time–I’d expand endlessly across the universe in one instant. The problem, as I see it, with “space-time” is that time is not at all like space, but we treat it mathematically as if it was just another dimension. Time is a phenomenon we experience in our minds, and maybe that’s all it is. But at this point we depart physics into philosophy.
Max Born said that theoretical physics is philosophy, not science. It tends to be bad philosophy, too.
Speculation and Fantasy
Nothing was observed.
They have yet to prove what the detected wasn’t a temporal wave.
I just spent half an hour looking for the article I’m about to talk from… If anyone can point me in the right direction I’d appreciate it.
The thing that concerns me about the LIGO results (and like ‘ggm’ I am concerned about models that just pop out the required data) is a report from a few years back about jitter in the system.
Basically the article talked about LIGO having tuning issues due to jitter in the beams and how they’d tried to negate all possible sources. Then along came a guy working in hologram universe areas and he showed the jitter was at the correct scale to be caused by a hologram ‘magnification’ like seeing dots in a newspaper photo that aren’t visible in the original photo.
He suggested the jitter was from the expansion of planck measurements because of the effects of the hologram at the boundary of the universe being magnified into the volume of the universe.
So if LIGO is measuring at a scale so tiny, I wonder what the models did to compensate for the jitter?
It’s important to note that any signals announced must have been seen at each of the widely spaced, independently run LIGO sites before being considered legitimate.
As an obstacle to any single detector, jitter is certainly one of several issues needing to be resolved to gain higher & higher levels of sensitivity (studying the deformation of space caused by the orbit of the Jovian moons about Jupiter, e.g.). However, this jitter naturally appears differently to the separate detectors involved because of their separation in space, & since any signal received at a given detector is compared to those received at the other detectors as well, those types of artifacts are fairly easily filtered out as “noise” at the scale of events currently being observed.
As a side note, plans are afoot to take some excess (for lack of a better word) materials from the Hanford, WA site to construct a 3rd LIGO site in India in addition to the one in Louisiana. (The VIRGO site in Italy is technically a separate project, though collaboration is understandably frequent.) This will among other things allow better directional sensitivity when it comes to locating these events in the universe relative to our world, as well as further filtering of ambient regional & local noise sources.
“As the two neutron stars spiraled together 130 million light years away, ”
——–
Talk about old news.
this is lol. Neutron stars defy the laws of physics
I understand they defy the laws of known physics, Mark. It isn’t neutron stars that are behind–it’s us mere mortals who haven’t a clue yet.
“Neutron stars defy the laws of physics”
A lot like climate scientists then.
Perhaps it’s something to do with their infinite density.
A ‘Breakthrough’ is:
1. A breakthrough is the discovery of a physical observation that if correct, absolutely disproves a theory.
2. The discovery of a new theory that supersedes the old theory.
3. A breakthrough is also the discovery of why we are not getting a breakthrough(s). i.e. Where to look for the breakthrough, It is not an argument.
A breakthrough is something exciting and interesting.
A jump up and down breakthrough is the discovery of something which we could not have imagined before the discovery of the physical phenomena which led to breakthrough and/or a breakthrough that leads to other breakthroughs.
Quantum mechanics is an example of a jump up and down breakthrough.
The detection of what we assume are ‘gravity waves’ is in accordance with our General Relativity model/theory.
There is no breakthrough. The finding is absolutely very interesting. It appears there are ‘gravity waves’ created from the interaction of neutron stars, and the wave travels at the speed of light.
Ironically it is a fact that there are now a couple of jump up and down breakthroughs.
There is now an absolutely hard paradox in the astronomical data. It is physical not possible for the old theory to explain the two population of stars in globular clusters.
Normally when there are a hundred or so observation anomalies (many close to physical paradoxes) and now a hard paradox (the multiple populations of stars in globular clusters are absolutely physically impossible to make with collapsing gas clouds and nuclear synthesis) with the old theory. There would have been the announcement that the theory in question is in crisis, followed shortly by the announcement that there is a new theory to replace the old.
Our Big Bang Theory has been incorrectly called a theory. It is more than a theory. It contains assumptions which observations now unequivocally show are absolutely incorrect at a very basic, fundamental physical level.
We made the most important fundamental physical choice in physics (affects everything in physics and metaphysics) 40 years ago when we selected the BB Fixed Time Universe based on the observations at that time. The natural physical alternative to fixed time universe was an Infinite Time Universe.
The unavoidable conclusion regarding an infinite time universe is that God(s) is an absolute certainty.
The metaphysical questions are interesting however the place to start is the key physical observations and the basic logical structure of the problem.
Part of the problem is the Coles Notes summary in textbooks concerning the BB fixed time universe is not critical and is inaccurate.
For example:
The BB fixed time universe CMB paradox.
Based on the BB theory the small angle variance of the 2.7k signal (CMB) which is assumed to be cosmic determines the lumpiness of matter distribution in the BB universe.
To get stars to form that microwave signal needs to vary on small scales no less than around 1/3000 to 1/5000.
The signal which we assume is the CMB varies on small scales as 1 part in 100,000, a factor of twenty too smooth.
The problem is based on BB theory a very smooth CBM that varies as one part in a 100,000 would result in matter being very eventually distributed in the universe. If that was true there would be no galaxies or stars formed.
The route of that problem in terms of observations is there is a great deal of empty space between the clusters of galaxies.
The theoretical solution to the BB CMB paradox, was the creation of new physics to Inflate the entire universe at 100,000 times faster than the speed of light. The problem with inflation event is it must only happen once. If it happens again the universe expands.
The BB theory would be in crisis without the addition of the inflation event. Inflation is a forced change in the laws of physics to keep the BB theory alive.
The argument for adding the Inflation event is it was believed at the time when the Inflation event was hypothesized that the other logical pillars of the BB theory were sound and would remain sound, with more advanced observations.
There are other issues with the CMB.
More than half of the raw signal is removed. There is a large unexplained cold spot. In addition, there is alignment of the large features of the signal with the axis of the solar system which would imply that more signal needs to be filtered out.
At the time when the 2.7k signal was discovered there was no alternative explanation for its existence. Text books state that there is no physical method to create the 2.7 k signal beyond a big bang event 13.8 billion years ago.
Obviously, it might now might be possible to come up with a local explanation for its existence, particularly as there is a hard paradox that the BB theory is incorrect and a hundred observations that are anomalies, close to paradoxes with the BB theory.
Some people are now arguing that the BB event could occur without the creation of the CMB, to avoid the bad inflation problems which come if we assume eternal inflation.
If that is true, the BB event occurred without a CMB, the signal which we observe is local not cosmic. We would then not require inflation and the inflaton field to explain the CMB too smooth anomaly.
The Inflation event is however still required to explain the universe is flat observation. One of logical pillars for the BB theory was the belief that observations would show the universe was either open or closed, as the BB theory without inflation naturally produces either an open or a closed universe.
The point is the Inflation event does not appear naturally from standard physics. It was specially created for the BB theory. At this point in time it appears, that the inflation add-on to standard physics will not lead to a breakthrough in fundamental physics.
http://physics.princeton.edu/~cosmo/sciam/
Science gets its ‘life’ so to speak from solving problems on a live path.
If you are on a dead path, it does not matter how smart you are or how long you work on the problem. It is impossible to make any real progress. I.e. To get the breakthroughs.
I did not take the time to elaborate, but I did not mean “God” in any religious sense.
There was a Star Trek episode involving an encounter with being shacking up with an earth woman on his very own planet. Turns out the being is a god, and the woman is facsimile he created because the original, which he loved greatly, was killed by a some faceless race of belligerents.
The salient point for me in this episode was that, in response to his wife’s death ( let’s assume common law principles in that part of the universe for the moment), this small g god willed the perpetrators entire race out of existence, from the entire universe, as if they had never happened, which is a profound concept, especially if the reverse is possible.
I really hesitate to even broach this discussion due to the risk of endless anthropomorphic gobbledygook,
but given an infinite amount of time, anything is possible, the god factor may not be all that metaphysical.
I really appreciate you comments, the BB theory was always a bridge too far for me.
Don’t we all love those paintings, so dramatic, so beautiful. Surely a front cover?… of? Ligo , the acronym says it all really. Utter nonsense. Well done boys, more dollars to fund the heliocentric whirl, where unproveable science is your god. Rock on Santa..
Got me thinking of Starquake by Robert L. Forward. A successor novel to Dragon’s Egg where humans meet the Cheela, inhabitants of a neutron star. They are the size of a sesame seed and live a thousand times faster than humans. How would they have perceived this event?
Wonderful series.
One day the house of cards will fall. Then we can get back to the way things actually work. Faraday, Tesla, and Heaviside had a much better understanding of physics. But it will take the effort of a fringe scientist to make the next leap. We spend billions on complete nonsense. But there are signs that the house built by particle physics is coming to an end.
Where are the visible light pictures???
I do not know about breakthroughs in terms of detecting gravitational waves.
What I do know is that vast improvements in technology made the discovery possible. Go to the LIGO website and read about the care which has been taken to filter out extraneous noise. Read about the mirrors which are mounted on an incredible series of vibration-damping devices. Read about the laser which is carefully monitored so as not to introduce noise. Read about the thousands of times the light is reflected from mirror to mirror. We see reports about four mile tubes. But the signals travel some 4,000 miles because of the multiple reflections.
Read about the extraordinary tubes, evacuated to a very hard vacuum. When one seeks a dimensional shift of 1/100 the diameter of a proton, one is seeking a very small shift. All kinds of advances in technology have had to be made to build these devices. Another entire topic is the ability to synchronize the timing used in the evaluation; atomic clocks are flown back and forth to bring the timing down to the femtosecond level.
It has been a long journey since Joe Weber first wired up piezoelectric detectors to a large chunk of aluminum to do this search. And the double neutron star collision is important, because of the observations at all wavelengths (these observations have not occurred with black hole mergers).
As for event horizons, there is most certainly a region from which electromagnetic energy cannot emerge. What else would you call it than an event horizon? And there is little agreement on the situation within the boundary (how can we possibly observe what cannot radiate)? The discovery that Hawking made about energy leaking from a black hole is another amazing discovery. You may not be a believer in quantum foam, but there certainly must be an explanation as to why small black holes are not found. And the pair production in quantum foam is certainly believable.