Above: The Existence Of White Holes.
A black hole is a region of space where so much mass is packed together so densely that it forms what is called a singularity, and nothing can move fast enough to escape its gravitational pull—not even the fastest thing in the universe (we’re talking light) can escape the clutches of a black hole.
And because light can’t escape, no one can really see what is going on inside a black hole. So we end up relying on theories and equations to deduce exactly what is happening at the center of the event horizon.
There are two competing explanations to describe black holes: Einstein’s theory of general relativity and quantum mechanics.
Albert Einstein’s theory of general relativity states the mass of a black hole bends spacetime so much that it becomes one single point of infinite density, but according to quantum mechanics there cannot be an infinitely small point.
It can be very very small, but not infinitely so. And this irreconcilable difference is one of the greatest debates in physics, since general relativity is our best description of gravity, while quantum mechanics has been called the most successful theory ever.
But some physicists believe white holes could square these two predictions. Find out more about white holes and how a white hole could reveal what is really happening inside a black hole on this episode of Elements.