is taken away by gravitational waves. In this case, two black holes ~35 times the mass of our sun collided, and the energy of the gravitational waves was on the order of a couple of suns through e=mc^2. That's a lot of energy converted!
Now, about 15 years ago I read an SF book which posited making a sort of gravitational laser (gaser?). That also used black holes, but they were miniture. I'm kind of wondering whether this could be a possibility: it may be possible to make mini black holes with powerfull accelerators, and then they could be chanrged by shooting electrons into them. The black holes could then be moved with electric fields. So it should be at least possible to get two black holes vibrating in sync to set up standing gravitational waves between them.
Now for the amplification part of laser/gaser: atoms absorb energy and metastable materials stay in excited state longer before emiting energy as photons. Gravitons would be the quanta of gravity but have not been observed, so it's hard to imaging what could fill the place of the gas or other material in a laser. Would particles that have mass respond to the standing waves and is there some way they could be excited and then give that energy to the grav beam?
Probably far beyond speculative.
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