- #1
Buckethead
Gold Member
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I'm a bit confused as to why the speed of light changes in an accelerating ship relative to an onboard observer. In other words, on a ship with a clock at the nose and a clock and observer at the tail, in an accelerating ship, the clock at the nose will tic faster. The reason (according to a Feynman lecture) is that tics (flashes of light for example from the nose clock) will be more closely spaced as the accelerating ship overtakes each flash pulse while they are traversing the ship from nose to tail.
If we view the acceleration as a series of constant velocities with instantaneous accelerations in between each different velocity, then at any given time (regardless of the velocity) the time it takes for light to travel from the nose to the tail will always be c. The problem with this of course is that instantaneous step in between velocities. But my difficulty with this is why does the light arrive sooner (in other words travel the distance faster than c) just because the ship is accelerating? If we start with the law that light always travels at c when measured in an inertial frame, why wouldn't light also travel at c in an accelerated frame. Is it just one of those "that's the way it is" situations?
If we view the acceleration as a series of constant velocities with instantaneous accelerations in between each different velocity, then at any given time (regardless of the velocity) the time it takes for light to travel from the nose to the tail will always be c. The problem with this of course is that instantaneous step in between velocities. But my difficulty with this is why does the light arrive sooner (in other words travel the distance faster than c) just because the ship is accelerating? If we start with the law that light always travels at c when measured in an inertial frame, why wouldn't light also travel at c in an accelerated frame. Is it just one of those "that's the way it is" situations?