Thanks man I appreciate further explanation but it doesn’t really answer my question.

Let’s say you have a beam that can shine north and south at the same time. It is positioned in the middle of 2 readers. We assume the clocks are not in sync. Shouldn’t we be able to get the time that the beam arrived in both sides and come up with a number regardless of what the clock says?

We would have the exact time the beam was turned on and we have the arrival time.

This post was edited by BigFat on May 28 2021 01:45pm

Syncing clocks is just a short hand to say knowing the starting time. You have to know the starting time on each clock when you fire the photons and that is dependent on the speed of light in the reverse direction