If black hole sucks in all masses, why does it suck in light if it is a form of energy (energy does not have mass)?

Question

I have been searching for a long time for the answer.

Answer 1

All energy has relativistic mass $m=E/c^2$, but a particle of energy $E$ and momentum $p$ has rest mass $\sqrt{E^2/c^4-p^2/c^2}$ in special relativity, and in general relativity (which gives us black holes) something similar but more complicated. The important point is that, while photons have zero rest mass, they do have relativistic mass.

Answer 2

1. stress-energy bends spacetime (not mass)

2. photons travel along the bent spacetime

3. a black hole has a lot of energy, and it bends spacetime so much, that it is so curved that it only leads towards the center

4. so once light gets close to the hole, it goes into that curved part and the only way is towards the center, light cannot escape anymore, that is why we do not see any information (EM waves) coming from the hole