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## Main Question or Discussion Point

My simple description of gravitational waves is that they are due to the relativistic principle of locality, i.e. the fact that the action of gravity is not instantaneous, something that you can’t see from the tidal effects in Newtonian physics. Is it correct?

I've also found a comment explaining them by "the principle of action equal reaction, which is true in GR too", so it would be " understandable that the acceleration of two bodies toward each other asks for and equal and opposite release of energy."

Well, such an answer appears to be IMHO unnecessary complex in the context of distinguishing relativistic from classical physics.

Anyway, one could simply answers that question about the nature of this release of energy, saying that it is mass, lost and transformed into gravitational waves. In fact it is the standard answer here. Is it true?

But if you invoke the relativistic conservation of momentum, then it looks like you’re going to introduce mathematical complexity, pseudo-tensors and advanced staff like jet bundles… and finally one needs to introduce parallel transport so that you can get an “energy conservation law” in integral form. Look at Baez link and also this question. What about these concerns?

P.S.

A second point of my question (maybe this is really a distinct question, sorry!): it is also unclear to me why/whether gravitational waves would be initially a quantum effect, related to quantum fluctuations (as opposite to e.g inflation waves). They are predicted by GR, so I fail to fully understand the relation with quantum fluctuations... but I assume it would be some huge effect of dark energy in GR, like bursts of gravitational waves generating other gravitational waves (is it actually possible?)

I've also found a comment explaining them by "the principle of action equal reaction, which is true in GR too", so it would be " understandable that the acceleration of two bodies toward each other asks for and equal and opposite release of energy."

Well, such an answer appears to be IMHO unnecessary complex in the context of distinguishing relativistic from classical physics.

Anyway, one could simply answers that question about the nature of this release of energy, saying that it is mass, lost and transformed into gravitational waves. In fact it is the standard answer here. Is it true?

But if you invoke the relativistic conservation of momentum, then it looks like you’re going to introduce mathematical complexity, pseudo-tensors and advanced staff like jet bundles… and finally one needs to introduce parallel transport so that you can get an “energy conservation law” in integral form. Look at Baez link and also this question. What about these concerns?

P.S.

A second point of my question (maybe this is really a distinct question, sorry!): it is also unclear to me why/whether gravitational waves would be initially a quantum effect, related to quantum fluctuations (as opposite to e.g inflation waves). They are predicted by GR, so I fail to fully understand the relation with quantum fluctuations... but I assume it would be some huge effect of dark energy in GR, like bursts of gravitational waves generating other gravitational waves (is it actually possible?)