Question

What is at the bottom of a black hole?

Answer 1

If you use Einstein's theories to determine what occurs at the bottom of a black hole, you'll calculate a spot that is infinitely dense and infinitely small: a hypothetical concept called a singularity. But infinities aren't typically found in nature.

Answer 2

A white hole.
A white hole is opposite of black hole and unlike blackhole it repels all the objects coming towards it. Two white holes of different black holes have wormholes or inter dimensional path. So if you jump inside the black hole then you can probably meet your twin in another dimension. I suggest you to read string theory. You will like it.