Question

what is the black hole theory ?

Answer 1

A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.

Answer 2

Blackholes in short are deep holes in the fabric of space-time.

Blackholes are deep curvatures or pits in the space-time which extend to infinity. They are caused be super dense objects like the remanant of star after it has undergone a big supernova. Light travels parallel to the curvature of space-time fabric and that is why when a light enters a blackhole it keeps on going towards infinity thus it never returns, so we call it a blackhole. At the end of a blackhole is the singularity where the laws of physics break down (for example: the law of conservation of information). Our universe originated from a singularity.