If theoretically in the centre of black holes there's a singularity and the big bang formed from a singularity Are there any theories suggesting that these two things are related?

Answer 1

In drawing a mathematical curve, the point of a sudden change is called a "singularity"; it means that the math at that point doesn't give an answer that makes sense.

At our current understanding of physics, the math doesn't make sense for gravity that is so intense that not even light can escape. We cannot describe in mathematical terms what is going on there, and we use the term "event horizon" to denote that area of space around the singularity where we cannot calculate what is happening.

The Bing Bang is also an area where the math doesn't seem to make sense; hence, a "singularity". But it isn't the same kind of singularity, or at least, we don't THINK it is the same.

However, in a very real sense, they are the same; we're saying "I don't know". It would be nice if physics and math had all the answers - but it doesn't. There is more yet to learn that all that the human race has ever learned until now.