In the general theory of relativity, the speed of light  in vacuum is $c$. In the special theory of relativity, a postulate is made that the speed of light is the same (called $c$) in all inertial frames. Consider the following statement: &quot;The speed of light is $c$ in all inertial frames but it can vary in accelerating frames.&quot; My question is: Does this statement violate the principle of equivalence or the special theory of relativity or any fundamental law of physics?
I'm studying special relativity and saw the 2 postulates of Einstein. The most remarkable one for me is the universal speed of light. Einstein postulated that the speed of light in vacuum is the same for all inertial observers, regardless of the motion of the source. But what if we are accelerating and we are changing from one inertial frame to another, how will we observe the speed of light? Is it still the same? I suggest it's not? Because I alread saw a small introduction to general relativity where the light will bend in a gravitational field and therefore also when you accelerate. So does the speed of light change because it bends?
The speed of light is the same in all inertial frames.  Does it change from a non-inertial frame to another? Can it be zero?  If it is not constant in non-inertial frames, is it still bounded from above?