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This question (basically an analogy ) is inspired by several questions and answers that appeared on stackexchange. 

We first define GASER, for the purpose of this question.

GASER - gravitational (wave) amplification by stimulated emission of (gravitational ) radiation. 

Many relevant questions and answers (relevant in relation to my question) can be found on stackexchange. 

Are gravitational waves transverse or longitudinal waves, or do they have unique/unknown properties?

Since there are gravitational lenses, are there gravitational mirrors?

Why do lasers require mirror at the ends?

What is Chirped Pulse Amplification, and why is it important enough to warrant a Nobel Prize?

Chirped pulse amplification, combined with fibre lasers and spectral beam combining can lead to some very powerful lasers. 

Black holes  (even microscopic ) cannot yet be created and manipulated at will. Assuming this will be possible in the future (that's a big IF , but this is a theoretical question ),  are there any suitable distributions of black holes ( and regular matter ) in space - time that would make a GASER possible?  

Cristian Dumitrescu
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  • This stimulated emission is a QM thing, and quantum gravity isn't existing yet. – peterh Oct 07 '18 at 21:51
  • An engineering impossibility, starting right off with the creation and manipulation of black holes which isn't possible in the even distant future. – ohwilleke Oct 07 '18 at 21:56
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    This question has a more than very one speculative part and it's really well outside mainstream physics, hence my close vote. It's not an uninteresting question in it's own right, just outside of what can be dealt with on Physics SE (IMO). – StephenG - Help Ukraine Oct 07 '18 at 21:57
  • @SolomonSlow It is known that binary black holes, in close orbit, generate gravitational waves, with the peak when they merge. I am thinking of a space - time region where black holes (probably microscopic ones are already created in particle accelerators ) are continuously created and merge (in an organized manner ), thus generating gravitational waves. An expert in GRT and QM might imagine a different way. – Cristian Dumitrescu Oct 07 '18 at 23:33
  • Rotating black hole under certain conditions would amplify electromagnetic and gravitational radiation around them (the phenomenon is called superradiance). For EM radiation it is possible to construct reflective shell around the black hole so that radiation is amplified up to catastrophic results: so called gravitational bomb. For gravitational radiation amplification factor could be greater than for EM, but it is difficult to make a reflector for the gravitational waves. – A.V.S. Oct 09 '18 at 15:30

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Probably not, for the following reasons:

Roughly speaking, lasing occurs when a photon passes close by an atom that has had one of its electrons lifted into a metastable energy state, where the decay of that electron would generate a photon of exactly the same wavelength as that of the passing photon. The decay is triggered by the photon's close passage and the new photon matches the phase, wavelength, and direction of the other. Then you put reflectors (one of which is partially-mirrored) at opposite ends of the chamber containing a large number of such excited atoms so after bouncing around within the chamber, many of the resulting photons will be following parallel paths along the axis connecting the mirrors; when the resulting coherent beam becomes strong enough, it will emerge from the partially-silvered mirror as a laser beam.

No one knows how to generate a convenient population of gravitons at will, or how to point them into and then confine them within a potential well so as to quantize their allowed energy states, or how to excite a large number of them into an energy population inversion and retain them there, or how to de-excite them with more gravitons, or how to make a half-silvered mirror for gravitons.

niels nielsen
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  • You are absolutely correct, thank you for your answer. I must add some (admittedly highly speculative ) remarks. Any region of space - time with a high matter density , in accelerated motion, is a source of gravitational waves. According to some models, collisions in high energy particle accelerators are a factory of microscopic black holes, and probably of gravitational waves of certain frequencies . Also, superconductors could be used to build resonant cavities for gravitational waves of certain frequencies . Please read the question about gravitational mirrors. – Cristian Dumitrescu Oct 08 '18 at 08:14
  • In this direction, it might also be useful to read about Podletnikov's experiments in gravitational shielding. – Cristian Dumitrescu Oct 08 '18 at 08:19
  • I'll have a look and let you know if it is within my powers to comprehend. – niels nielsen Oct 08 '18 at 08:34