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Big Bang Really a Big Hum
benna writes "The New Scientist reports, 'The Big Bang sounded more like a deep hum than a bang, according to an analysis of the radiation left over from the cataclysm. Physicist John Cramer of the University of Washington in Seattle has created audio files of the event which can be played on a PC. "The sound is rather like a large jet plane flying 100 feet above your house in the middle of the night," he says.' Apparently the idea for the project came from an 11 year old."
The reason you can't hear sound in space is because it's almost a vacuum. Back around the time of the Big Bang, matter was packed much closer together and density was far higher. Much higher, for example, than the density of the Earth's atmosphere. So yes, sound vibrations could propagate around in the early universe.
Even if sound can't travel through space due to the the sparse particles to set in motion... their should still be some particles set in motion after all they were created in pretty much the same instance as the sound itself were created...
I win. :)
This came up on the BBC Radio 4 interview with the scientist responsible, incidentally. I believe you can discover his response at the BBC website, assuming this is the interview that was broadcast this morning.
++ Say to Elrond "Hello.".
Elrond says "No.". Elrond gives you some lunch.
Jesus fucking Christ! Stop it already you retards!
You won't? Well, let me get in the game then. Definition of sound is not "pressure variations in air". It is: "pressure variations in matter (solid, liquid or gaseous) interpreted by our ears and brain as sound". Nitpicky enough?
Close but sound is a compression wave through some medium. It does not have to be air. It could be air as we commonly experience. It also could be water, iron, or any other element on the periodic table. in other words it is the compression and expansion of matter that is what we experience as sound.
Enjoy some truly cosmic drum 'n bass!
Actually, we have very accurate data telling us what the spectrum of acoustic oscillations or "sound" was at the time of the "decoupling" of photons and matter, which was only about 350,000 years after the big bang. You might want to check out the technical papers coming out of the WMAP project, to which I have no affiliation. They've produced the most accurate maps of this acoustic noise, and this is the data that was used to make the "sound recordings". Seems kosher to me, and IAANP, so you can trust me :-)
This is just taking energy fluctuations and "resampling" and scaling into the narrow band of frequencies (approx. 20Hz-20KHz) that we perceive as sound.
You can do this with anything--I wouldn't be surprised if some site somewhere lets you "hear" the Sun's recent plasma ejection.
This is not what you would have heard if you had "been there", folks.
This kind of pseudo-science is even more useless than the "what color is the universe" articles. I guess people love to be able to relate to hard-to-comprehend things with their senses.
Nothing to see here, folks, lets just move along and go back to our arguments about whether the universe is shaped like a donut or a soccer ball.
bp
and here I am thinking this whole time that slashdotters were intelligent. Another dream I once had shot down in the flaming vacuum of space. OMG I said flames in space, how could that be, because you need air to have fire, right? I think http://www.badastronomy.com would be a useful link for most of you people who have absolutly NO understanding of anything outside of the 6 inches of grey matter inside that skull of yours.
Space itself streched, the matter did not move apart. Think of a ballon with dots on it, as you inflate the balloon, the dots move apart due to the stretching of the medium they are embedded in. There are no constraints that we know of on the speed that space can stretch at.
Here's an ogg format of the sound file:
http://tools.waglo.com/bigbang.ogg
I can only swim about 3 miles per hour. If you put the swimming pool on the back of a truck, I could still only swim at 3 mph within the water, but that doesn't mean that there would be a 3 mph limit on the truck moving the pool itself.
The Buddhists were right!!
For those who may not know, the "AOM" sound that people make when they are meditating (you know, "a-ummmmmmm") is supposedly the sound the universe made when it was created.
Chalk one up for them, I suppose.
--Stephen
Did you ever notice that *nix doesn't even cover Linux?
The wavelengths of the vibrations have nothing to do with the size of the propagating medium. Some funny things can happen if the wavelength is much bigger than the the propagating medium (for example, think of a low frequency wave in a small room - the wave doesn't propagate, instead the whole room is pressurized). If this wasn't true, home audio/home theater would suck since bass response in most rooms would be limited to ~100 Hz.
Of course as some other posters have mentioned, physics were different during those first moments, so this hole explanation could be moot ;)
Perhaps it's more accurate to describe it as a compression wave, since "sound" is only the effect of a compression wave that propogates through a medium and ultimately interpretted by our ears.
First of all, this sound is based on observations of the microwave background radiation, which didn't come into existence until 300,000 years after the big bang. You will note that the article states "when it [the universe] was just 18 million light years across" Imagine beating a drum that big, and you'll see why the pitch is so low. So the big bang may or may not have been a "bang" but 300,000 years later, the sound made was a hum.
:) Some folks seem to be trying to detect it indirectly via the microwave background.
Really, the relevant signal to listen to is the background signal of gravitational waves. These actually correspond rather directly to (faint) sound waves, since they induce mechanical disturbances as they pass through matter. By now, of course, most of these will have stretched to the dimensions of the universe, and be more or less undetectable, even in principle. Some theories predict the existence of higher frequency waves going back to the first moments of the big bang. We can look forward to detecting some higher frequency waves in the next five to ten years, from the various interferometers coming online. This is serious science, and could provide insights into not only the origins of the universe, but also supernovae, and the dynamics of black holes and neutron stars. Not to mention curiosities that may occur unheralded. Something akin to the advent of radio astronomy may be in store for us.
There's also (presumably) a neutrino background, from about one second after the big bang. This will be very hard to detect, until we build a big sister to AMANDA covering icy orb, perhaps ganymede
Physicists are entitled to a little fun now and then, anyway. It also helps to bring cosmology a little closer to the general public. It certainly isn't as if this researcher had to get a peer reviewed grant of many thousands of dollars to produce such "trivial" results: he simply did some starightforward processing on data that was already available, quite possibly in his spare time on his own computer. Oh, and I would definitely classify this as more useful/pertinent then that (admittedly a bit silly) "color of the universe stuff"!
It is not the case that "any" sound can be created, or that there is no relationship to the original, when scaling by 100,000. Many (most) relationships are preserved in this sort of operation. Indeed, a familiar example would be to speed up or slow down normal speech; it remains understandable.
Science starts with the presumption of ignorance, and then proceeds to discover what the universe can tell us about itself. Many slashdotters could take a lesson from this.
The two most abundant things in the universe are hydrogen and stupidity.
Harlan Ellison
Those people who think they know everything are a great annoyance to those of us who do. (Isaac Asimov)
Shouldn't that read: 'A 16" gun can shoot a Volkswagon 352 football fields'?
This is because scientists are people and people are imperfect. However, science as a whole is pretty effective at discarding bad theories, even if scientists aren't. It just takes a generation or two.
... They are all wrong. We know they are wrong. And like you said, we won't stop using them until a better theory comes along. And like in the case of NG/GR we may still use the old theory.
It's also important to remember that bad theories, once established, do not die until a theory that is clearly better comes along. Until then, the bad theory is kept, and patched to fit the evidence
I think you are mixing things in your head.
Bad theories still get used because they can still have utility. Today we still use Netwonian Gravity, because it works fairly well and its a million times easier than GR. But we know that NG is wrong. And we know that Newtonian mechanics is wrong. But its easy to understand and its easy to calculate.
I'll give you an even better example. We know (physics) that every single theory we have is wrong. GR is classical, QED is bad at small distances, QCD is bad at large distances,
If we all put our calculators down everytime we figured out how one of the fundamental theories was wrong, then we would never get anywhere.
Now aside from that there are old foggy scientists that will never convert from aether theory to that new fangled relativity. But this is a completely different process, and it is much less important - because those old grey physicists don't publish much and they don't have nearly as much impact on the community as the young guns. Physics today is a young man's science (peak at 30), and this is why we are focusing/wasting so many minds on completely unfounded things like string theory.
The main problem you state lies in long time rivalries between semi-unproven theories. Right now Quantum Loop Gravity is a rival to String Theory. String people say "hey you're not Lorentz invariant". And the Loop people say "so what, Poincare sucks, we use an A/DS universe. you're using a background metric, you can't quantize gravity with that, duh" to which the string people reply "er, um, its perturbative quantum gravity" or "we believe classical gravity only gets the waves right perturbatively anyhow"
Perhaps in the future, after we have quantized gravity, things will settle down once again and the old people will rule.
A Usenet Troll Triumphs on Slashdot
Read up on cosmic inflation.
The Big Bang was a Troll against catholic physicits pushing a scientifically viable theory to creationism: the primordial egg was proposed by a gesuit priest. Try reading E. J. Lerner's "The big bang never happened", it's a wonderful book and gives pretty sensible explanations to cosmological data; shame that no scientific institution wants to question the enstablishment... perhaps those that run the business built their careers on these theories?
Mi domando chi à il mandante di tutte le cazzate che faccio - Altan
Check out the Transactional Interpetation of Quantum Mechanics. Critiques of all the well known interpretations (CI, MWI) and others you may not have heard of.
You will not drink with us, but you would taste our steel? - Walter Matthau, The Pirates
Stephen Hawking in A Brief History Of Time starts with the anecdote. A well-known scientist (some say it was Bertrand Russell) once gave a
public lecture on astronomy. He described how the earth orbits around the sun and how the sun, in turn, orbits around the centre of a vast collection of stars called our galaxy.
At the end of the lecture, a little old lady at the back of the room got up and said: "What you have told us is rubbish. The world is really a flat plate supported on the back of a giant
tortoise."
The scientist gave a superior smile before replying, "What is the tortoise standing on?"
"You're very clever, young man, very clever," said the old lady. "But it's turtles all the way down."
(ripped off from http://www.the-funneled-web.com/hawking.htm)
Carthago delenda est!
mmm I suspect people read plancks laws, the uncertainty principle by Heisenberg and read some of Niels Bohr' works. Not just read Einsteins general or special theory of relativity. Might want to try reading Sir Isaac Newtons Principia Mathematica as well. I would logically say that given the uncertainty principle, and quantum physics as per plancks definitions, sound would not have occurred. As some others have pointed out, sound may have occurred after the big bang, from when time and space started to behave under 'normal' known physics. Anything prior to that is well...unknown. Several people such as Stephen Hawking & Roger Penrose have suggested in the past that time was a by product of the big bang. Well, time as we know it. But that's another story ;-)
Einstein himself had several heated debates with Niels Bohr and did not like the uncertainty principle or Quantum physics either. Hence his great comment "God does not play dice".
Dave
Slashdot can go and get fucked.