Hi. I've been reading about relativity and time dilation. Also watched some visualisations on youtube. The question I have is about the light clocks which are always used to demonstrate the theories. Explanations always show the light beam on the moving clock moving in a diagonal motion, zig-zaging up/right and down/right. As the diagonal path is longer, the clock runs slower.(adsbygoogle = window.adsbygoogle || []).push({});

This implies that light emitted normally from from a source inherits the momentum of it's source, thereby providing the left-->right component of it's diagonal path.

Is this correct? It seems counter intuitive. I always assumed that a moving (left to right) light source would emit its beam, which would go straight up and be left behind by it's source, which is continuing on it's way along the x-axis.

Just to make sure i'm clear, I'd expect that light emitted (pointing upwards along the y-axis) at time=0, x=0, velocity=v, would at time t be located at x=0, y=ct. These light clocks make it look like at time t it would be located at x=vt, y=ct.

Can anyone help? Thanks : )

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# About how light clocks would work

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