Cosmoes

I've been reading Einstein: His life and Universe by Walter Isaacson and have arrived at a section on general relativity.

As I understand it the theory of general relativity predicts that the amount of matter in our universe causes space and time to curve back in on itself and our universe can be thought of as existing on the surface of an expanding balloon.

As I thought about that I wondered if it were possible that our universe were inside a black hole, and if other black holes were universes that we are on the outside of.

It is interesting to me that a black hole is known to form after a super novae, which means there is a mighty big bang.

As I understand it matter comes from stars too.

I haven't got the math skills to investigate the idea, or the background to know if this is an absurd idea, yet isn't it lovely to consider such questions even for a moment?

It is said that not even light can escape a black hole. This is because the gravitational mass bends it back on itself is it not?

Could it be...