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inflector

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https://www.physicsforums.com/showthread.php?t=433866" that relativistic time dilation does not depend on acceleration, i.e. that there are instances where the acceleration might be zero while there would be significant time dilation. The example in the other thread was gravity and acceleration in the core of a spherical planet where there would be time dilation due to the gravitational potential even though there would be no acceleration due to gravity.

This made me wonder about time dilation itself.

Would it be equivalent to look at gravitational time dilation, not as time slowing down but rather as inertia increasing? Would there be any way of experimentally differentiating between these two perspectives? I.e. how can one tell the difference through experiment between the inertial mass of a system proportionally increasing and time slowing down?

It seems to me that one would only be able to determine inertial mass by looking at the effect of a given force on the acceleration of the mass using the equation F = ma. However, since both time (through the second derivative of position implied by acceleration) and mass are present in the formula, one can't really distinguish between time slowing down and inertial mass increasing.

Does this mean that gravitational time dilation could also really be seen as gravitational inertial mass increase if the two perspectives are mathematically equivalent? Or am I missing something obvious again?

This made me wonder about time dilation itself.

Would it be equivalent to look at gravitational time dilation, not as time slowing down but rather as inertia increasing? Would there be any way of experimentally differentiating between these two perspectives? I.e. how can one tell the difference through experiment between the inertial mass of a system proportionally increasing and time slowing down?

It seems to me that one would only be able to determine inertial mass by looking at the effect of a given force on the acceleration of the mass using the equation F = ma. However, since both time (through the second derivative of position implied by acceleration) and mass are present in the formula, one can't really distinguish between time slowing down and inertial mass increasing.

Does this mean that gravitational time dilation could also really be seen as gravitational inertial mass increase if the two perspectives are mathematically equivalent? Or am I missing something obvious again?

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