Lost in the collision was an enormous amount of energy in the form of a gravitational wave, a ripple in space that travels at the speed of light.... Because the detectors allow scientists to pick up the gravitational waves as audio signals, scientists actually heard the collision. For all the violence and drama, the signal lasted only a tenth of a second. “It just sounds like a thud,” Weinstein said. “It really doesn’t sound like much on a speaker.”So... it was heard as a tenth-of-a-second thud after traveling at the speed of light — light, not sound — for 7 billion years. I don't think they really heard the crash, but they picked it up, one way or another, after 7 billion years. It's mind-blowing to think of how far away that was.
३ सप्टेंबर, २०२०
"This crash happened about 7 bn years ago, when the universe was half its current age, but is only being detected now because it happened so far away."
From "'It just sounds like a thud': astronomers hear biggest cosmic event since big bang/Researchers believe noise was two black holes colliding around 7 billion years ago, creating a previously unseen class of stellar object" (BBC).
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Well, after 7,000,000,000 years plus or minus a few.
How astronomers know the things they claim to know.
My ex wife would prefer me to be even further away.
Weinstein said. “It really doesn’t sound like much on a speaker.”
Come on Weinstein. Listen harder!
Two black holes colliding? You must have been able to pick out the N-word.
Scientific proof the universe is structurally racist!
Nobel Prize to be quickly awarded.
"Because the detectors allow scientists to pick up the gravitational waves as audio signals, scientists actually heard the collision."
Ah, no.
It was a dud thud.
A universal one.
Go figure.
It sounded like a vote for Biden.
And was almost as old.
These astronomers all have fancy degrees and titles, and I'm sure they know what they're talking about when it comes to planetary orbits and comet composition, etc.
But this super esoteric stuff? Signals from deep space? They're just making shit up, and nobody can or will call them on it.
Whatever caused this sound cannot possibly be known by us with even the smallest degree of certainty.
Claims like this only serve to undermine their credibility...
With the right equipment someone several years in the future will be able to review everything you've done and said in your lifetime. Seeing it and hearing it doesn't consume it so your life experience could continue to zoom along in space for many others to see some day. That is if it doesn't degrade over time or bump into absorptive materials.
I was expecting an earth-shattering Kaboom.
I don't think they really heard the crash, but they picked it up, one way or another, after 7 billion years.
Think of it as a digital to analog conversion. It is kinda like that.
I heard it.
Narr
More like a cough than a thud
"Star collapses could not create stellar black holes much bigger than 70 times the mass of our sun, scientists thought,
Then in May 2019 two detectors picked up a signal that turned out to be the energy from two stellar black holes — each large for a stellar black hole — crashing into each other. One was 66 times the mass of our sun and the other 85 times its mass."
So these two black holes essentially were at the expected upper limit of current theory. Cool.
"The result was the first known intermediate black hole, at 142 times the mass of the sun."
Cool squared.
"Thud" is a bad term; these are gravity waves that make no sound, were first postulated in 1905, and only detected four years ago. Had the collision between two black holes of in total 142 solar masses happened seven billion and four years ago, they would have gone unnoticed. Wrap your head around that one.
I don't think they really heard the crash, but they picked it up, one way or another, after 7 billion years.
You are right, it's not a sound they didn't actually hear it.
"They detected the signal, which they have labeled GW190521, on May 21, 2019, with the National Science Foundation's Laser Interferometer Gravitational-wave Observatory (LIGO), a pair of identical, 4-kilometer-long interferometers in the United States; and Virgo, a 3-kilometer-long detector in Italy.
The signal, resembling about four short wiggles, is extremely brief in duration, lasting less than one-tenth of a second."
I remember 7 billion years ago--when we were still allowed to socialize.
I blame Trump.
Well, if you think you know the distance the wave traveled, you can estimate the energy required at the source.
Also, are we still calling them black holes? I thought that term had been cancelled.
It's certainly pedantic to complain about “hearing” when there are no sound waves passing between the event and us. Because one can't talk about “seeing” it either — seeing involves electromagnetic waves (of a particular range of frequencies) — and this event far away in in spacetime involves not only the wrong frequencies but the wrong whole spectrum — not electromagnetic at all, but gravitational waves — a completely orthogonal spectrum of frequencies to electromagnetic waves (carried by gravitons rather than photons, when speaking particles rather than waves).
Only a pedant would wish to strip away any and all vocabulary which might effectively describe what was observed. Both “hearing” and “seeing” really come close enough!
If not, what's next? Complaining about the “seeing” of the forthcoming James Webb space telescope — because it “sees” infrared radiation, which (though electromagnetic) is invisible to human eyes?
Whatever caused this sound cannot possibly be known by us with even the smallest degree of certainty.
Modern theoretical science is the art and practice of plausible. Their assumptions/assertions are implied, including the fidelity of the signal. At worst, it's a conflation of logical domains that people will take for granted because of the expert source.
I don't think they really heard the crash, but they picked it up, one way or another, after 7 billion years.
Humans have to translate all this stuff into forms we can observe and/or understand. Audible, visual, mathematical, neurological. No different than how humans experience anything, really.
...and now, off to smoke some weed and watch the original Cosmos...
Here's a decent write-up about detecting gravity waves with interferometers.
Here are some pictures (scroll down) showing how interferometers can be used visualize minute imperfections in glass, similar to how they can detect the minute perturbations in gravity caused by the waves.
"it just sounds like a thud." Researchers believe noise was two black holes colliding around 7 billion years ago...
Maybe they should put a glass to the wall and listen closer...
"Ohh - scissor me timbers!"
"Had the collision between two black holes of in total 142 solar masses happened seven billion and four years ago, they would have gone unnoticed. Wrap your head around that one."
Yeah, it suggests that such collisions were not rare 7 billion years ago, or the detector picked up something much closer and smaller in size.
I have one son who is going to love this news. Related and sharing because this post is likely to draw people interested in astronomy: anyone else use Slooh?
I don't have any hopes for personal immortality, but the cosmos is such a strange and wondrous place that I don't completely rule out the possibility.....On the plus side, we didn't inhabit the universe during the worst possible era. Even if the global warming freaks are right, how bad is a hot spell compared to those damned meteor showers that sometimes befall Planet Earth.
Feeling small yet. Then try studying atoms . If not try studying their electrons and protons. And then.try to think all that creation was directed by and held together by an accident.you will finally have made peace with Darwinism.
All they are really saying here is that the frequencies of the gravitational waves they are detecting are in the range of tens to thousands of Hertz -- the same frequency as sound. So when they detect these signals, they can convert them into a sound wave and we can 'hear' the wave. Similarly when we listen to the radio, we are listening to a signal in this same frequency range that's been extracted from an electromagnetic wave -- which was also travelling at the speed of light but for rather a shorter time! In the case of the radio, we're inverting a process by which we initially translated a sound wave into an electromagnetic one. Presumably that is not the case here!
What if they're just making it up to entertain or mollify everyone?
Kind of like the general orthodoxy/"settled science"'s ideas about Egypt and Peru, notwithstanding the tube drill and circular saw marks plainly visible on ancient stones and boxes ostensibly cut and shaped with rocks and brass chisels?
"and released an enormous amount of energy, equivalent to around 8 solar masses"
That's about 16*10^30 kg, 2,664,000 times the mass of the Earth, converted into energy.
Compare to:
The Hiroshima atomic bomb converted about 700 milligrams of mass to energy.
That's a little under 1/3 the mass of a dime (2.27 grams), and released about the same energy as 30 million pounds of dynamite exploding.
Joe Smith: But this super esoteric stuff? Signals from deep space? They're just making shit up, and nobody can or will call them on it.
This isn't true. Astrophysics isn't that speculative. On the contrary, ever since Einstein wrote his General Theory of Relativity and had to wait a decade for experimental support, which eventually came in droves, we've had more and better experiments to conduct to test various hypotheses, including hypotheses about the long-term history of the universe. No credible physical theory contradicts the Big Bang. No credible physical theory contradicts the existence of black holes. No credible physical theory proposes a fixed space/time background a lá Newton. We know as well as we know gravity makes an apple fall from a tree that mass curves spacetime, which we call "gravity," and black holes are enormously massive, so a black hole collision is going to cause an enormous gravitational, hence spacetime-warping, hence detectable, event.
Achilles: Think of it as a digital to analog conversion. It is kinda like that.
Very good analogy, in fact probably not an analogy at all: it's overwhelmingly likely that the "audioization," by analogy with "visualization," was done with Fourier transforms, exactly as digital to analog conversion is done.
Blogger Joe Smith said...
These astronomers all have fancy degrees and titles, and I'm sure they know what they're talking about when it comes to planetary orbits and comet composition, etc.
But this super esoteric stuff? Signals from deep space? They're just making shit up, and nobody can or will call them on it.
Whatever caused this sound cannot possibly be known by us with even the smallest degree of certainty.
I don't think that's a fair assessment. Gravitational waves have been predicted for decades. They built detectors to find them and then did. Classic science. If only climate science was on such solid footing.
Dr. Althouse: So... it was heard as a tenth-of-a-second thud after traveling at the speed of light — light, not sound — for 7 billion years. I don't think they really heard the crash, but they picked it up, one way or another, after 7 billion years. It's mind-blowing to think of how far away that was.
The mind-blowing part is that the speed of light in a vacuum is a constant, so the only way we have to express "how far a photon traveled in 7 billion years" is to say "7 billion light-years" or, put slightly differently, "about half the size of the visible universe," but this is misleading because the universe is not only expanding, but accelerating in its expansion.
"On the plus side, we didn't inhabit the universe during the worst possible era."
Obviously not written by a Democrat.
In our long ago language that would be "far out man!"
The French National Centre for Scientific Research is famous for its voluminous research projects but there are reasons to be cautious about their work. Almost every search turns up with a warning:
"The performance of the CNRS has been questioned, with calls for wide-ranging reforms. In particular, the effectiveness of the recruitment, compensation, career management, and evaluation procedures have been under scrutiny."
Consider that 75% of CNRS funding comes at the behest of liberal French politicians as extracted from French citizens. Then examine the technique used to obtain research papers for publication. The most recent notice to all registered researchers was sent out defining subject parameters thus:
“Carbon Weather: Toward the next generation of regional greenhouse gas inversion systems”
Accepted here is the suspect premise that there is a naturally coupling of the carbon cycle and the climate that result in "greenhouse gas" effects likely caused from anthropogenic air pollution. We can forget evaluations of absolute correlations resulting from sun spot activity and Sol's cosmic ray pulses effect on our cloud cover.
Modern cosmology makes super massive black holes (black holes with masses above 1 million solar masses) a necessary foundation for the formation of galaxies.
The problem is there's no theory that explains the creation of super massive black holes. Rut-roh....
So: massive collision, sending waves unimaginably far over an enormous span, detected by the most ingenious machinery, and all we get is -- what?
All that energy leaves me cold.
To those that say they're not making it up...
Gravitational waves may be real, but these guys have NO idea what is the cause. They can speculate all they want. I can too.
Remember the story a year or so (can't remember) ago about the star dimming and then brightening? Reputable scientists were speculating about an alien civilization building a Dyson sphere as a possible cause.
Really? Maybe it was just your mom's fat ass getting in the way of the light.
Equally probable.
Kind of kidding but kind of not.
And don't even get me started on String Theory...
Just like the amount of oil and natural gas we used EVERY DAY it is very difficult to comprehend the numbers. That is why the renewable energy zealots never get it right.
Achilles: Think of it as a digital to analog conversion. It is kinda like that.
Very good analogy,
Not really; a much better analogy would be the conversion inaudible electrical impulses into sound by running them through a transducer, namely a speaker.
in fact probably not an analogy at all: it's overwhelmingly likely that the "audioization," by analogy with "visualization," was done with Fourier transforms, exactly as digital to analog conversion is done.
DACs don't typically use Fourier transforms; FTs are used to convert from time (or space) domain to frequency domain (and the reverse), typically to convert raw data to compressed data (e.g. to mp3 or jpg files), and vice-versa (compressed file back to digital data). Other filters are used when converting analog to digital to avoid aliasing, by removing frequencies above the sampling frequency (~Nyquist/2). Visually, uncompressed digital data can be displayed directly on your monitor as discrete dots and is converted to analog by your eyes and nervous system.
Blogger Tom McGlynn said..."All they are really saying here is that the frequencies of the gravitational waves they are detecting are in the range of tens to thousands of Hertz"
I didn't realize that. Fair enough.
Needed a stop sign, there!
"Remember the story a year or so (can't remember) ago about the star dimming and then brightening? Reputable scientists were speculating about an alien civilization building a Dyson sphere as a possible cause."
The Dyson sphere stuff was wild speculation and was admitted to be such by the couple of people who were doing the speculating.
"Black" holes???
That's racist.
Obviously we need to cancel and get rid of them. Just like we need to get rid of racist rocks.
Paul Snively said...
The mind-blowing part is that the speed of light in a vacuum is a constant, so the only way we have to express "how far a photon traveled in 7 billion years" is to say "7 billion light-years"
Wrong on two counts:
1) We can express that distance in any unit of length: miles, microns, feet, or furlongs (or countless others). We use light years because they are the largest standard unit, and also because it makes it easy to track the time/distance relationship for astronomical events: if you know how far away it is, you know how long ago it was, no conversion necessary.
2) The mind-blowing part is that it took no time for the gravitons to get here.* Since they are traveling at the speed of light, time stands still for them. They were at their starting point, ending point, and all points between all at the same time.
* from their point of view, which is every bit as valid as our point of view.
In a day or so God's voice will reach their ears saying "O, shit. What the fuck was that?"
John Henry
Now gravitons, they're a myth (IMHO).
...or furlongs...
I recall a grade school assignment where we had to use dimensional analysis to convert 55mph into 'furlongs per fortnight'...
“In astrophysics, we’re always faced with surprises,” Weinstein said.
You mean science itself is not settled?
Fifteen 'confirmed' gravitational events have been observed over roughly two years, plus a much larger number of less certain events.
Two of these events are believed to be the collision of neutron stars, twelve are the collisions of black holes, and for one they believe a black hole collided with something large that they still can't identify.
The obvious hypothesis when you look at the data is that this is how supermassive black holes, as for instance the one at the center of our galaxy, form.
List of gravitational wave observations
There is a great deal of uncertainty in these observations, and thus in the actual paper on the event being discussed here they claim that the collision happened somewhere between 2.7 billion light years and 7.7 billion light years away from us. The gravitational wave created by the merger, a ripple in space-time, passed through the Earth on May 21, 2019.
It took roughly a year to analyze the May 21st data and extract as much information from it as was possible. And some pretty complicated statistics were used to come to this conclusion.
Now I have no reason to believe that this is not a real event. But in real science as opposed to the image of science that the media creates there are often people that disagree. And one of the people that questions the whole thing has as it happened made an entertaining video on the subject:
Sabine Hossenfelder: Have we really measured gravitational waves?
but then a year later she made this, which kind of implies that she now thinks the detections are valid, or at least might be valid:
Sabine Hossenfelder: Black Hole Echoes
I don't think they really heard the crash, but they picked it up, one way or another, after 7 billion years.
next, you'll be telling rhhardin, that he doesn't REALLY hear the code signals; that it's all just a beat frequency oscillator that he's hearing
I love Hossenfelder's blog. Her book is well worth a read, too.
YoungHegelian said...
Modern cosmology makes super massive black holes (black holes with masses above 1 million solar masses) a necessary foundation for the formation of galaxies.
The problem is there's no theory that explains the creation of super massive black holes. Rut-roh....
*****************
See this:
https://astronomy.com/news/2020/09/scientists-detect-first-mid-sized-black-hole-via-gravitational-waves
It addresses both the gravitational wave issue and the critical link between intermediate and super-massive black holes.
Also, what the wave "sounds like" has nothing to do with sound. It's the sound made by the detector. Gravitational waves are generally very low HZ, at the low end of human perception. That wave makes no sound at all as it travels through the cosmos. A sound wave needs a medium, like air.
And @ Joe Smith: your ignorance on this topic is clearly in the "super-massive" category.
My theory is that the thud was just a dog whistle.
I am gonna go out on a limb and say that the odds that we would detect the second event to the Big Bang by building the detectors in almost the exact precise less than even an instant to detect it suggests that this was pretty common.
"But in real science as opposed to the image of science that the media creates there are often people that disagree”
It’s like the warmies. We have the bottom fifth of students who become journalists describing the work of the top 1% of students.
"I am gonna go out on a limb and say that the odds that we would detect the second event to the Big Bang by building the detectors in almost the exact precise less than even an instant to detect it suggests that this was pretty common."
That's a pretty strong limb. I sure would like to see the catalog of events after a century of observation, not to mention a millennia.
When we hear a really big wet fart, we'll know we've picked up the Big Bang.
These guys would be fun to prank, but it would probably have to be way more creative than the Sokal type stuff.
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