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Originally Posted by Genadinee
So, why does light get pulled into a Black hole? I was under the impression that light being an electromagnetic wave would be able to run away but the very thing 'black' hole is or was thinking because light cannot escape from it.
Genuine question btw if you can explain it to me would be cool.
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It is indeed a good question, and confused many physicists for years. Photons have no mass. How can they possibly experience a force from a black hole then!! Isaac Newton, who came up with the first theory of gravity, explained gravity as a force like any other. Force = Mass of object / (distance from object)^2 . According to this theory of gravity, light could escape no matter how great the mass of a black hole.
However, Einstein (a smart guy) refined the theory of gravity with what is now called the General Theory of Relativity. In his theory, the force of gravity is a geometrical force. (The math here is really complicated so I have to make some bad analogies). You can think of it like this, take a sheet with stripes. The stripes are the paths that a photon would follow (straight lines). Now drop a large weight onto the sheet. It will deform the sheet.
Now if you look at the lines, it appears that they bend toward the mass. This is the geometrical nature of the force. Mass warps "spacetime" and that forces the straight line paths of photons (these are called geodesics for anyone wanting to study more math!) to bend toward the mass.
Now if you drop a bunch of large masses onto the sheet, they will all end up in the same area (if they are close enough together). If they are heavy enough, they will rip through the sheet. The mathematical term for this is called a "singularity" and it is a point of infinite bending of the "spacetime" sheet. That is a blackhole. All the stripes on the sheet entering the "black hole" get stuck there because of the rip in the sheet. They have no path to follow back out.
As I said, it's a bad analogy. You can prove from the math that you need to travel faster than the speed to escape, but I was never good at General Relativity and so I cannot remember how to prove this at the moment :>(