If a photon is massless, how does a black hole "swallow" light and with tremendous gravity not let it escape?

Answer 1

Photon: its energy is E = hf and its momentum p = mc. Also its momentum is E/c. So
hf/c = mc. Then m = hf/c2 (or more known: m = E/c2)
So a photon has mass.
Since it always moves with c, it has no rest mass.

Photons are attracted by any mass, so also by a black hole.
Also here you can say: mass attracts mass.

Answer 2

Even though the photon is massless, any mass "bends" the space time continuum around it, according to general relativity. The denser the mass, the more the bending. Light always "tries" to go in a straight line, if spacetime is flat. But when spacetime is curved, as around a black hole, the light follows "geodesics"--the shortest path between two points, which may no longer be a straight line. So, light is sucked in because it is traveling along a geodesic in curved spacetime, which wraps around the black hole. The paths of a photon that cross inside the "Schwarzchild radius" of the black hole stay inside that radius. A little further out than that radius, the curvature of spacetime is less, but still badly deformed. Photons that pass slightly outside the S. radius take very wild curly orbits the may wrap around the black hole several times before exiting. At exactly 1.5 times the S. radius, a photon will "go into orbit" around a blackhole, because geodesics at that distance are circles with black hole at the center! Further out than that, the deviation only creates a deflection in the path as it the photon passes near the black hole.

Answer 3

Photons have zero "rest mass". However they do contain energy (and therefore mass) and are affected by gravity. This is actually an important prediction of general relativity. (see the first few sentences of the link below.)

Answer 4

No one has ever escaped a black hole. It appears that black holes and photons are here to stay though no one has ever seen one.
no one can see a photon ;
no one can see a black hole.
no one has made a shadow of gravity or energy.
All assumptions are purely speculations.
Proof is when we are able to test and see.

Answer 5

if an elephant is tiny, why cant he fit in a thimble?

Your assumption that a photon is massless is wrong.