Talk-Polywell.org

I think we are finally getting somewhere.

There is no change in the A frame, since A stays in one inertial frame. There is a change in the B frame, from S1 to S2.

Hence the two equations are not the same, viewed from B, which changes frame, or A, which does not.

I have been saying this for some time, but perhaps this will help you more than previous posts.

Note that the time shift element is nothing to do with relative velocity changing. When calculated in B's frames it is independent of the velocity of A, and depends only on the change in velocity (and therefore frame) of B and the distance between B and A in the S1 (or S2) frame. Thus it is not symmetrical between A - which never changes frame, and B, which changes from S1 to S2.


Time shift is a correction needed in a relativistic world when an observer's frame changes. It affects all his calculated times of distant clocks. These times must be calculated because direct comparison is impossible. The change in (calculated) time of a distant clock seems a bit weird but not when you consider that in relativistic space there is no such thing as absolute "now". The set of spacetime events corresponding to "now" depends on the frame in which "now" is measured.

Thus the distant clocks do not change time, rather the distant clock time considered the same as the local time varies when the local frame changes.

is anyone sure this isn't some maths quirk, quantisation issue, overflow or something like that?