Why is the speed of light said to be constant when we know it slows down in a medium?
23937
What is the mechanism behind the slowdown of light/photons in a transparent medium?
65533
Does gravity slow the speed that light travels?
66523
Does the optical density of a medium depend upon its mass density?
115239
Is the Speed of Light an universal spacetime constant, the velocity of electromagnetic waves, or of photons?
96657
The speed of light as it approaches a massive body
152064
Why does change in speed of a wave make it refract?
72913
Why does a light wave fade as it travels through space?
120679
Rømer's determination of the speed of light
148196
Does the speed of light in different mediums affect the lorentz transformation?
974
Speed of light in a gravitational field?
22118
If all motion is relative, how does light have a finite speed?
55971
Why does the (relativistic) mass of an object increase when its speed approaches that of light?
12597
Does the speed of medium affect the path of light?
7618
What is the speed of light relative to?
31825
Why are objects at rest in motion through spacetime at the speed of light?
123933
Why is causality preserved in special relativity?
67127
Does the speed of light vary in non-inertial frames?