Tabletop experiment could detect gravitational waves

Tabletop experiment could detect gravitational waves
(Phys.org)—A coin-sized detector might observe gravitational waves before the giant Laser Interferometer Gravitational-Wave Observatory (LIGO), according to two Australian physicists.

Predicted by Einstein's general theory of relativity but yet to be directly observed, are ripples in space-time generated by accelerating massive objects. The tiny detector has been made by Dr Maxim Goryachev and Professor Michael Tobar at The University of Western Australia.

Resonant-mass detectors have traditionally employed metal bars about a metre long and around a tonne in weight, which makes them sensitive to gravitational waves with frequencies up to about a few kilohertz. However, tiny vibrations that would be induced by gravitational waves are extremely difficult to detect above the thermal noise in the bar.

Dr Goryachev and Professor Tobar overcame this problem by targeting in the 1-1000 MHz range. Operating at temperatures as low as 0.01 K above the absolute zero, these devices are able to operate at the quantum regime allowing for the lowest possible noise level.

Their device consists of a quartz disc about 2.5 cm in diameter hinged to another piece of quartz and placed in a vacuum chamber. A passing high-frequency gravitational wave would cause the disc to vibrate, setting up standing waves of sound across the 2 mm thickness of the disc.

The upper surface of the disc is slightly curved to trap sound quanta (phonons), which improves the signal-to-noise ratio. The nature of quartz allows the tiny vibrations to be converted into an electrical signal that is amplified by the extremely low-noise Superconducting Quantum Interference Device (SQUID) amplifiers.

Having accounted for all known sources of noise, Dr Goryachev and Professor Tobar believe their detector would be sensitive to strains in space-time as low as 10-22 per share root of Hertz, the figure that Advanced LIGO is set to achieve.

Advanced LIGO is an upgrade of two existing LIGO detectors in the US, which are searching for gravitational waves. The huge detectors are expected to detect signals between about 0.1-1 kHz, from sources such as binary neutron stars or colliding black holes by the end of 2018.

Dr Goryachev and Professor Tobar say that their device is able to detect gravitational waves from some candidates such as axions and preons forming tiny stars and black holes.

The setup is also able to put limits on gravitational radiation from the early Universe predicted by some Big Bang theories.


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More information: Gravitational wave detection with high frequency phonon trapping acoustic cavities, Phys. Rev. D 90, 102005 – Published 24 November 2014, journals.aps.org/prd/abstract/ … 3/PhysRevD.90.102005
Citation: Tabletop experiment could detect gravitational waves (2014, November 28) retrieved 26 June 2019 from https://phys.org/news/2014-11-tabletop-gravitational.html
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Nov 28, 2014
per share root of Hertz

...that should probably be "square root".

If it works: very cool (no pun intended).

Nov 28, 2014
The principle problem with all gravity detectors whether the Earth based LIGO, VIRGO, GEO600, CLIO, or space based LISA/eLISA, DECIGO systems is the frequency of false positives. This SQUID system holds the promise of being able to create a network of these smaller detectors at many different locations around the world, preferably in University controlled settings to supplement not supplant other detectors. No one is going to be "first," all properly calibrated systems should see the same spike at approximately the same time. Good luck with that.

If we're riding a really big gravitational wave, we may not be able to detect it, until we wipe out.

Nov 28, 2014
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Nov 28, 2014
Err - the problem with any of these detectors is that there are earth generated vibrations in virtually every frequency regime caused by everything from volcanic activity to orbital vibrations due to the gravitational variations from the Sun.

Personally I don't hold out any hope for any way to guarantee that you are measuring gravity waves or vibrations.

Nov 28, 2014
Well the problem with these detectors is that the very computers that run them will set them off. The issue is that we are chasing a phantasm. It is one error staked upon a theory about another error. There are obvious facts about gravity and much other stuff but they are ignored routinely to chase the deity Einstein who was just plain wrong on such. Physics needs to get its head out and learn about the Electrical nature of the universe. Look Einstein said a theory of universe formation that makes comets "dirty snowballs". Look 6 comets visited and counting and now we find nothing but high temperature formed rocks! The theory of the Electrical Universe predicted accurately the theory of Einstein and Big Bang and Kant's nebular Hypothesis screwed up. Fix your scientific method!

Nov 28, 2014
Err - the problem with any of these detectors is that there are earth generated vibrations in virtually every frequency regime

Not at the speed of light.
Well the problem with these detectors is that the very computers that run them will set them off.

Why would you think that?

There are obvious facts about gravity and much other stuff but they are ignored routinely

Such as? Cite those facts. With observations, please. (Congrats on your new sockpuppet, BTW. Let's see how long it lasts this time)

Nov 28, 2014
A Professor from Zurich, Schneider, claimed in the mid 70's that his cockchafers were detecting gravity waves, I did produce an alternative explanation at the time based on accepted Physics. I had done some work about Gyroscopes in brains of Pigeons as recent papers claim (see JEB November 2014).

Nov 28, 2014
Nobody dddaarrre say it, so I will. Have no job to protect....no career to 'save'...no 'reputation at all'. Speed of gravity is many times 'c' if it has a limit at all. Look to other sources for this and they abound. C'mon trolls! 'One' me to show your intelligence and/or sperm count. I know there are ladies on here even if none passed my calculus classes....does not mean they did not pass other calc and diff-e-q classes, etc. Have yet to encounter a lady troll..or idiot.

And, trolls, tell us why astronomers routinely have to 'correct' for real observations of transluminal speeds to 'set their records straight' (protect their careers...just like universal denial of UFO's, etc)!! ....and do not divide by zero or some such like our notable one did....somewhere!

Nov 28, 2014
@osiris - It's nice to be daring. But your examples are incorrect. Perhaps the best known evidence for the speed of gravity equalling the speed of light is in the precession of Mercury, which was not understood until general relativity came along. You can also look at the orbital frequency of binary pulsars - the orbital speed winds down at a rate that is determined (among other things) by the speed of gravity. These and various other tests have all confirmed that the speed of gravity is c.

As for correcting for transluminal speeds - I'm a physicist not an astronomer, but I recall from an astronomy class I took that when stars are moving at the right speeds and angles with respect to an observer, they can appear to undergo superluminal motion. But that's just a "trick of the light" so to speak.

Some links:
Speed of Gravity - http://www.mathpa...h527.htm
Apparent Superluminal Motion - http://jila.color...re29.pdf

Nov 28, 2014
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Nov 28, 2014
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Nov 28, 2014
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Nov 29, 2014
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Nov 29, 2014
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Nov 29, 2014
No gravity waves will be found, 'cos there ain't any "gravity". The effect called "gravity" is caused by universal expansion, there is no proof that gravity exists as a force although it has proved an excellent model for reality.

Nov 30, 2014
Al right, I shouldn't be posting. I've had a few drinks. But this is what just popped into my drunken head, so let's see what people make of it.

Everything Space born seems better. I won't explain it, it just is. So get this experiment out into space. Put it way out there where the influences are minor. Now here is my really pished bit. Build 'as perfect a sphere as you can' and make it rotate like a gyroscope, then measure its precession. Look for changes over time with observed astronomical events. Maybe even go 3D gyro's. Hmmm I think I might be describing the Gravity Probe B sats. Shhhhhhh.

I shall say no more and simply show myself the door.

Nov 30, 2014
@Reg Mundy. I understand your point of view. It is very easy to think that gravity is an apparent force, I too have thought this many a time. However, all we can currently go by, until some breakthrough is achieved, is that CURRENT BEST THEORY predicts that it is a field with a force transmitting particle known as the Graviton, if Quantum Theory and its derivative/analogues are to be believed. Time and time again I suspect gravity is nothing more than a topological phenomenon, and its apparent discrepancy of magnitude with other forces gives rise to scientific suspicion. But when Gravitons fall out of String Theory, then I have to rethink think this idea. Sure M theory is nothing more than a theory, but its ability for self consistency always make me think again and again. I can't push M Theory under the carpet, as I suspect it will be a brilliant mathematical analogy that will move us forward, once the calculations part are solved.

Nov 30, 2014
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Nov 30, 2014
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Nov 30, 2014
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Nov 30, 2014
Photons aren't considered to be massless nor do they carry mass, BUT they DO carry MOMENTUM. Refer to DeBroglie for simple explanation. Don't ignore established physics just to further your wild ideas @imido. You seem to be confusing MASS which belongs to a particle, with MOMENTUM which is apparent in a wave. Sure by following Feynams QED you can get confused as to which is which, but you must accept that a particle (if it indeed exists as such), is BOTH. M-Theory removes this ambiguity, hence is compatible with Feynman and this receives my tick of approval. Multiple dimensions beyond which is seen is the only explanation which resolves ALL problems as far as I can see. Come on, if the maths is constantly suggesting it, then go with the flow. Of course the maths must be resolveable, that is where the problem exists. But breakthroughs in the maths is occurring, just as Newton came up with calculus to solve the problems of his day. Give it time!!!! M-Theory IS the ANSWER!!

Nov 30, 2014
No gravity waves will be found, 'cos there ain't any "gravity". The effect called "gravity" is caused by universal expansion, there is no proof that gravity exists as a force although it has proved an excellent model for reality.
@regTROLL
personal conjecture without evidence
you still haven't been able to define tides, orbits, or anything, for that matter, here on PO without self referencing your supposed book and it's explanations

you are pushing a known pseudoscience and you have NO empirical evidence supporting your conclusions
the only links you have tried to use support mainstream theories and contradict you, especially with regard to your proportion problem
http://sci-ence.o...-flags2/
http://math.ucr.e...pot.html

you've never given ANY evidence that your PSEUDOSCIENCE is legit, and you even admitted that it is nothing more than a philosophy
so it is NOT science
trolling/baiting comments

Nov 30, 2014
No gravity waves will be found, 'cos there ain't any "gravity". The effect called "gravity" is caused by universal expansion, there is no proof that gravity exists as a force although it has proved an excellent model for reality.
@regTROLL
personal conjecture without evidence.
you still haven't been able to define tides, orbits, or anything, for that matter, here on PO without self referencing your supposed book and it's explanations

you are pushing a known pseudoscience and you have NO empirical evidence supporting your conclusions
the only links you have tried to use support mainstream theories and contradict you, especially with regard to your proportion problem
http://sci-ence.o...-flags2/

you've never given ANY evidence that your PSEUDOSCIENCE is legit, and you even admitted that it is nothing more than a philosophy
so it is NOT science
trolling/baiting comments


Trolling and baiting huh Stumpydick?
Exactly what you do! LOL! Get a life dude!

Nov 30, 2014
@DN
Stumpydick is on my ignore list, but I see his comment via yours. Suggest you put him on your ignore list, as he is a persistent stupid troll.
@BHJ
Not only no gravity, but no mass either, its all momentum and expansion according to my theory. As I've explained many times, it is impossible to put all the theory and diagrams into a context like phys.org, but I contend that there is no evidence for the existence of gravity as a force other than the beautiful correlation between the laws as invented by Newton and Einstein, and reality, whereas indirect evidence for expansion theory is derived from redshift if it is caused by time (expansion of photon) as opposed to the Hubble expansion of the universe which looks increasingly shaky.

Nov 30, 2014
Not only no gravity, but no mass either, its all momentum and expansion according to my theory.
@reg-troll
and as we can see here, the only references he has is to his book, and that is the worst possible classic pseudoscience trolling move
http://sci-ence.o...-flags2/
http://math.ucr.e...pot.html

Also take note that reg never supplies empirical evidence for his conjectures
this is another classic trolling pseudoscience trait

he also will misinterpret the links that he does try to post, while also failing to give any rational explanation for his fallacies which cannot be defined, like orbits, tides, and the lack of observed proportional differences due to his mass dependent expansion (his words: see a failed attempt at logic here: http://phys.org/n...ong.html )

in conclusion, always request empirical evidence from reputable peer reviewed publications with an impact in the subject

this will weed out pseudoscience like reg

Dec 01, 2014
There is no such physical effect as gravitational waves that are ripples in space-time generated by accelerating massive objects. Actually has gravitational disturbances that are expressed in constant change in the intensity and direction of the total gravitational field on certain subject in the universe. They are caused by the movement of numerous celestial bodies in the cosmic space and have so complex character that is not amenable to mathematical description. The idea that the space is deformed or time changes its course under the influence of massive objects are the product of human imagination, but have no confirmation in reality and there is no reason to have. Nothing in the universe will change if there were not these hypothetical effects and scieties and cosmologists forget about these ideas.

Dec 01, 2014
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Dec 01, 2014
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Dec 01, 2014
Personally I don't hold out any hope for any way to guarantee that you are measuring gravity waves or vibrations
Actually that's one of the easier aspects to assure, as Bob Osaka alluded to—with multiple detectors in different locations. The same wave will be seen in the data of each detector at times differing by an amount precisely predicted by general relativity with respect to detector locations and propagation direction of the wave. That was one of the reasons LIGO has interferometers in both Hanford, WA and Livingston, LA, and shared data with VIRGO and GEO600.

Dec 01, 2014
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Dec 01, 2014
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Dec 06, 2014
"Any possible g wave would fall off sharply from its source via 1/r sup 2 for the single initial pulse, it wouldn't be like a spring unless the mass is undulating someway...this means that by the distance of a light year away from such an event, for example, that pulse and any g wave produced by it would have been stretched out …smeared out into space-time, regardless of inertial frame of observation, unless of course the "graviton" which is suppose to be massless could hold the energy of the initial pulse but then this would pose a problem as the cosmos would be full of detectable g waves from many and all large scale event sources regardless of the degree or order of the Qs of detection."

As for the acoustic cavity high frequency phonon trapping to detect a g wave...be prepared for a long wait and hopefully the researcher can and will be able to tell the difference between a random and systematic experimental errors.

In essence, you and anyone trying this will find nothing.

Dec 06, 2014
follow the same patterns like the finding of Higgs boson - it will be announced ceremonially, the Nobel prizes will be distributed - and after few years the theorists will realize, they did measure something very different. Such a pattern provides the minimization of lost of job places and social credit for theorists involved
@ZEPHIR
there is no evidence that the Higgs wasn't what was found... you mistake articles for empirical evidence
and as for the technicolor stuff posted (which was a "maybe" thing anyway)... it was known before the find as well, so the information is the same as what it was after the Higgs find - irrelevant until proven

you are always so willing to accept any piece of news as valid empirical evidence
there is a difference, you know... oh, wait, maybe you DON'T know
especially given your support for daw/aw still regardless of this: http://arxiv.org/...1284.pdf

the rest is conspiracy BS

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