Re: Question about light clock - Part II

No we can not. Even in a laser, the light originally is sperical. (Open
it up, you will see the light eminate in all directions). The light
that "stays" in the long verical tube is the particular part of the
wavefront that had the correct horizontal speed. All the other parts of
the wavefront just hit the inner wall of the tube...

Drop a rock on the surface of water. The wavefront is sperical
(circular here) . Any tube coinciding its bottom with the rock-water
collision will have it's other end receive a particular part of the
wavefront.

See what I mean?

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