Shape from sound: New methods to probe the universe

April 3, 2013 by Mor­gan Kelly, Princeton University

( —As the universe expands, it is continually subjected to energy shifts, or "quantum fluctuations," that send out little pulses of "sound" into the fabric of spacetime. In fact, the universe is thought to have sprung from just such an energy shift.

A recent paper in the journal Physical Review Letters reports a new mathematical tool that should allow one to use these sounds to help reveal the shape of the universe. The authors reconsider an old question in spectral geometry that asks, roughly, to what extent can the shape of a thing be known from the sound of its acoustic vibrations? The researchers approached this problem by breaking it down into small workable pieces, according to author Tejal Bhamre, a Princeton University graduate student in physics.

To understand the authors' method, consider a vase. If one taps a vase with a spoon, it will make a sound that is characteristic of its shape. Similarly, the technique Bhamre and her coauthors developed could, in principle, determine the shape of spacetime from the perpetual ringing caused by .

The researchers' technique also provides a unique connection between the two pillars of and —by using vibrational wavelengths to define the geometric property that is spacetime.

Bhamre worked with coauthors David Aasen, a physics graduate student at Caltech, and Achim Kempf, a Waterloo University professor of physics of information.

Explore further: Proposed Spacetime Structure Could Provide Hints for Quantum Gravity Theory

More information: David Aasen, Tejal Bhamre and Achim Kempf. 2013. Shape from Sound: Toward New Tools for Quantum Gravity. Physical Review Letters. Article first published online: March 18, 2013. DOI: 10.1103/PhysRevLett.110.121301.

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Display comments: newest first

1 / 5 (5) Apr 03, 2013
Yes. Spectral geometry is my god. Science is not possible without this. Let us pray. lol
3 / 5 (4) Apr 03, 2013
preprint: it's only theory about theory, no actual results are presented.
1 / 5 (4) Apr 03, 2013
Ophelia? I am among the numberless that make a living with spectral analysis. What has not been imagined by form or shape?
1 / 5 (3) Apr 04, 2013
I have a question that's probably totally stupid but I'm going to ask anyway.
If these energy shifts as the universe expands make a type of sound then what is it's average frequency? And if the energy is spreading out wouldn't that mean that the frequency is slowly going down? In my odd logic following that possibility would indicate that eventually the universe will reach a maximum size once that frequency reaches zero or close to it but at the same time the universe would effectively be "dead"
Totally off in left field or somewhat possible?
1 / 5 (7) Apr 04, 2013
Spacetime doesn't exist.

c^2.t^2 - x^2 = S
S = 1.9121x10^-34 m^2 -- A universal constant as light speed.
i(S)^1/2 = Neutrino Compton wavelength (imaginary)

Antonio Jose Saraiva
vlaaing peerd
5 / 5 (3) Apr 04, 2013
morons don't exist, time does.

Considering 5.86x102 Joules is the energy of one beer, using D.Tomkins equations, time can be most easily described as:

1s = sqrt(E/μ²*ρ)beer/3

vlaaing peerd
3 / 5 (2) Apr 04, 2013
sorry, has to be;

1s = sqrt(E/μ³*ρ)beer1/3
1 / 5 (6) Apr 04, 2013
I put my name on --- idiots
5 / 5 (2) Apr 05, 2013
I put my name on --- idiots

You put your name on. So what! Are you trying to tell us that you are actually SURPRISED by the responses your posts have been getting?! Each time you post, your only contribution is to tell us that this or that does not exist and throw some ad hoc equation(s) without a genuine context out, as 'proof'. Do you actually expect any of us to take you seriously, with statements like that? If ever you tried to get that published the way you write those statements, you would get laughed straight off any pre-print site! Do you REALLY think that we are so moronic that you can confidently expect us to swallow your BS just because you post it? Where is your proof? Where is your evidence? How about either involving yourself in discussions for real, with real explanations, or stop posting at all. As they say, "if you have nothing intelligent to say, say nothing at all". Mate, if you ARE a GENUINE scientist, you REALLY should know better!
5 / 5 (2) Apr 05, 2013
Just remember, every time you pull a stunt like the one you did in this thread and many others, you re-enforce the impression for all of us, that you are just posting for posting's sake. In other words, being a troll. But then again, your very low ranking (I DO presume that you have managed to work out how to check/access that...) should have tipped you off by now that your hit and run technique is not working.
1 / 5 (4) Apr 05, 2013
c^2.t^2 - x^2 = S

No one knows this formula?
And this:
Spacetime = sqrt( x^2 y^2 z^2 (ict)^2 )

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