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Question: Since photons is consider matter. And an exploding star would probably spew matter into space faster than the speed of light. Would not photons travel faster then normal because of the force (explosion) that was behind it?
It is important to note that a photon is non-local. Meaning it does not exist at one point at any moment in time - rather, it is sort of spread out through all space with higher probabability densities at different points in space.
A photon is not considered matter - it does carry energy however. Whenever matter undergoes some process where it emits energy it does so via electromagnetic radiation which is made up of photons.
An exploding star would not accelerate a photon beyond c because a photon is a massless and electrically neutral entity - any force created by the exploding supernova would be a mass on mass or charge on charge interacting phenomenon (ie pressure, gravitational, electromagnetic...).
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Because if a black hole can retain light, and gravity can bend light. Then light is not a constant. Because if it can be bent from a strainght line. It can also be slowed while in forward motion. That is just a bend from the direction of travel.
A black hole does not retain light. A black hole warps space-time to such an extreme that light continues on a straight path in its own frame of reference through curved space-time and "falls" forever into the black hole. So really light is not bent - the space it travels through is bent.
The speed of light is the upper limit value through space-time. Nothing can exceed the speed of light. Light can be slowed on average - ie. absorption and emission by atoms for example, though the speed from the moment of emission to the moment of aborption is still c on average over a long path length light has been "slowed" because of the delay between the excited electron moving to a lower energy state and emitting a photon.
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Which also means that light leaving a high gravity star travels slower (bends backwards) until it escapes that star's gravity. Unless there is a law that prevents light from bending backwards?
The star with the highest gravity (besides a black hole) would be a neutron star. A neutron star is supported only by baryonic degeneracy pressure - the last barrier before total collapse. Picture a bowling ball on a sheet of elastic - the bowling ball represents the neutron star and the elastic represents space-time. If light passed by this bowling ball from our perspective it would appear to curve but in the lights frame of reference it would be continuing on a straight path because it is unable to leave the surface of the elastic and is thus unaware of higher dimensions. Here the elastic represents a 2D projection of 3D space - picturing space warping in 3D is too difficult (and probably impossible).