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dface

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I am having a hard time understanding a scenario that I have not found discussed elsewhere. It has to do with simultaneity and information content.

There are two digital clocks on either end of a spaceship. Clock L on the left, Clock R on the right. They have digital displays, showing time numerically when activated.

There is a man in the middle of the spaceship, call him S.

There is a man, at rest at position x=0, call him O.

The spaceship is moving at uniform relativistic speed to the right.

Previously, S has synchronized clocks L and R using light pulses sent from his position in the middle of the spaceship, while moving at this same relativistic speed. I understand that O and S will not agree about the clocks being synchronized under these conditions, but let us imagine that S programmed clock L to indicate a later time than clock R when it is first synchronized (for example 0:00 on L compared to 0:01 on R). Let this time offset be appropriate so that to O, the clocks appear to be in sync. From that point onwards, S knows the clocks will be out of sync by this offset, but that doesn't bother him because he is aware of it.

At t=0, O and S are both at x=0. The spaceship is still moving to the right, at the same relativistic speed used at synchronization. S sends out two photons, one towards the left clock and one towards the right clock. When these photons hit the digital clocks, the clocks radiate the numbers from their displays at that moment. These numbers radiate to the eyes of O and S.

Will O and S see different numbers from each clock? It appears to me that O and S will observe different pairs of numbers, but how can this be if the radiation was created at a single event? Clock L radiates numbers once, and clock R radiates once. How can that radiation carry different "information content" to the different observers?

There are two digital clocks on either end of a spaceship. Clock L on the left, Clock R on the right. They have digital displays, showing time numerically when activated.

There is a man in the middle of the spaceship, call him S.

There is a man, at rest at position x=0, call him O.

The spaceship is moving at uniform relativistic speed to the right.

Previously, S has synchronized clocks L and R using light pulses sent from his position in the middle of the spaceship, while moving at this same relativistic speed. I understand that O and S will not agree about the clocks being synchronized under these conditions, but let us imagine that S programmed clock L to indicate a later time than clock R when it is first synchronized (for example 0:00 on L compared to 0:01 on R). Let this time offset be appropriate so that to O, the clocks appear to be in sync. From that point onwards, S knows the clocks will be out of sync by this offset, but that doesn't bother him because he is aware of it.

At t=0, O and S are both at x=0. The spaceship is still moving to the right, at the same relativistic speed used at synchronization. S sends out two photons, one towards the left clock and one towards the right clock. When these photons hit the digital clocks, the clocks radiate the numbers from their displays at that moment. These numbers radiate to the eyes of O and S.

Will O and S see different numbers from each clock? It appears to me that O and S will observe different pairs of numbers, but how can this be if the radiation was created at a single event? Clock L radiates numbers once, and clock R radiates once. How can that radiation carry different "information content" to the different observers?

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