Subject: black hole "bomb"
OK...I haven't finished reading it. And when I do, I'm going to have to look up some stuff that I've never heard of. So it will take a while to digest.

https://www.livescience.com/sp...

In 1972, physicists William Press and Saul Teukolsky described a theoretical phenomenon called a black hole bomb, in which mirrors enclose, reflect and exponentially amplify waves emanating from a rotating black hole.

I will need to read this, also: https://en.wikipedia.org/wiki/...

Basically, scientists seem to have confirmed in a lab a theory from several decades ago. Seems to be pretty esoteric stuff, but I'll know better when I finish all the reading.