We all know about black holes. One of the most fascinating objects in the universe, and what is amazing is that they exist!
Now, what about white holes?
A quick reminder of what a black hole is
A black hole is simply a collapsed region of spacetime (what is called a singularity) with a one-way boundary called the event horizon, which is an incredibly dense and massive object, from inside of which nothing can escape, not even the fastest thing in the universe, light.
Back when Einstein published his field equations (that described the evolution of the shape of spacetime), black holes were part of the solution to them. At the time, they were nothing more than a mathematical curiosity. Now, we KNOW that black holes are very much real!
How are black holes created?
When a massive star dies and collapses, a black hole is born.
