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(physics) Alternative form of time dilation (less common)

From the local frame of reference of the blue clock, the red clock, being in motion, is measured as ticking slower.

(physics) Alternative form of time dilation (less common)

Left: Observer at rest measures time 2L/c between co-local events of light signal generation at A and arrival at A. Right: Events according to an observer watching as the mirror setup moves to the right: bottom mirror A when signal is generated at time t'=0, top mirror B when signal gets reflected at time t'=D/c, bottom mirror A when signal returns at time t'=2D/c

(physics) Alternative form of time dilation (less common)

Transversal time dilation. The blue dots represent a pulse of light. Each pair of dots with light "bouncing" between them is a clock. In the frame of each group of clocks, the other group is measured to tick more slowly, because the moving clock's light pulse has to travel a larger distance than the stationary clock's light pulse. That is so, even though the clocks are identical and their relative motion is perfectly reciprocal.