Lets say that you built a black hole generating machine outside our solar system maybe in 500 years or so. ( a black hole generator was already made on earth, but the black holes where so tiny, It couldn't do anything)
Lets say we create a black hole that exists for just a few minutes and disappears again.
OK. After these assumptions it is very obvious what we can do with this.
We are able to bend light. Now what should we do with a light-bending black hole-creating machine that costs most probably over 10.000billion dollars.
we can bend all light from all stars, sending it with light speed to other planets, even better, If there are intelligent Lifeforms out there they maybe have thought about this and use this invention already, meaning If we find a rithmus in the movenment of the stars we have proof, maybe we can encode this.