– Black holes and light

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This might be a little too complex but after Melvin Bragg this morning I started thinking.

Black holes are centres of mass with gravity so powerful that light cannot escape.

The speed of light is constant, and I understand (well know of, fully understand might be a bit far) that sometimes there is time distortion to keep it constant a la the Einstein train clock experiment.

However, how does this work with a black hole? Light photons are trying to move away but cannot? So they zoom out at the speed of light until they cannot and then go the speed of light in the other direction? They speed of light circle the black hole? Time doesn’t exist in a black hole?

In essence the question is how does one square the fact that the speed of light is a constant but it cannot escape a black hole?

In: 1

One way to think of it is that the photons have a constant speed through space, but according to general relativity gravity is the curvature of spacetime. In a black hole, the spacetime within the event horizon is curved in such a way that all trajectories lead to the singularity.

Black holes created extreme space time curvature. Space and time flip and space becomes one directional while you are free to traverse time. But no matter what direction you move you move towards the singularity direction itself in space makes no sense because inside the event horizon there is only one direction, towards the singularity.

If we know mass of the object, we can calculate speed required to escape that object.

The black hole is by definition so massive that escape speed is greater than speed of light.

So even black holes have theis escape speeds, the problem is that nothing moves fast enough. Hypothetically, if we had something that moves faster than light, it would be able to escape blac holes while light wouldn’t.