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In this question I've mentioned an account of the recently reported 2nd observation of gravitational waves, LIGO and Virgo Collaborations, Phys. Rev. Lett. 116, 241103, 15 June 2016, where 1 of the 22 solar masses is said to have been converted into pure energy - gravitational waves.

My question here is in two parts:

  1. Is there any standard theoretical framework where this energy could - in any way - transfer back to more "familiar" forms of energy, where "familiar" means mechanical, electrical, thermal... things less exotic than the energy being stored in the vibration of space itself.
  2. Is there any discussion of one way this might actually come about. Sometimes a theory that says something is possible doesn't by itself make it very obvious how it would be possible.

I'm looking for something carefully worked out and published, and not interested in any discussion of practicality.

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uhoh
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3 Answers3

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Feynman gave an argument of beads on a string or rod. The passage of a gravitational wave would cause the beads to move in a way similar to the arms of the LIGO interferometer. He argued that the motion might have friction on the string. We might think of this as magnets on a solonoid. If there are magnets at different places on the solonoid their motion would induce EMF by induction, and their motion would result in a net current and voltage across the solonoid.

Don't expect gravitational radiation to become any serious energy source. The coupling constant of gravitation is $8\pi G/c^4~=~4.12\times 10^{-45}N^{-1}$, which is very small. The Einstein field equation $G_{\mu\nu}~=$ $(8\pi G/c^4)T_{\mu\nu}$. For the right hand side the density of energy or momentum and the left curvature it is clear you need large curvatures to get large energy densities.

Lawrence B. Crowell
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This is from the Wikipedia article mentioned. I think this is really worth reading, as it not only describes some of the physics associated with the accepted answer and it's citation of Feynman's argument about a bead a stick, but perhaps gives a little insight into the development of the field as well.

Feynman's argument

Later in the Chapel Hill conference, Richard Feynman — who had insisted on registering under a pseudonym to express his disdain for the contemporary state of gravitational physics — used Pirani's description to point out that a passing gravitational wave should in principle cause a bead on a stick (oriented transversely to the direction of propagation of the wave) to slide back and forth, thus heating the bead and the stick by friction. This heating, said Feynman, showed that the wave did indeed impart energy to the bead and stick system, so it must indeed transport energy, contrary to the view expressed in 1955 by Rosen.

In two 1957 papers, Bondi and (separately) Joseph Weber and John Archibald Wheeler used this bead argument to present detailed refutations of Rosen's argument.(5)(6)

(5) Bondi, Hermann (1957). "Plane gravitational waves in general relativity". Nature 179 (4569): 1072–1073. Bibcode:1957Natur.179.1072B. doi:10.1038/1791072a0.

(6) Weber, Joseph & Wheeler, John Archibald (1957). "Reality of the cylindrical gravitational waves of Einstein and Rosen". Rev. Mod. Phys. 29 (3): 509–515. Bibcode:1957RvMP...29..509W. doi:10.1103/RevModPhys.29.509.

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uhoh
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In order to be detected, the gravity waves have to be converted to some other form of energy (eg mechanical, electrical).

So the answer to question 1 is Yes. The answer to question 2 is any article about gravity-wave detectors/detection.

sammy gerbil
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