- #1
Skeptick
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Synchronizing clock
The purpose of synchronizing clocks is so the time on one clock is as close a possible to the time on another clock. This can be achieved by any means possible to make the error as small as possible.
In Fig 0 the green bit is a laser that surprisingly emits photons. The red bit is a detector that detects the photons. Each emitted photon pulse is encoded with the exact time on it ie minute, second, milli sec, down to femto second say, using frequency modulation.
The clocks are synchronised by emitting the encoded photon from the green bit at A. When it strikes the red bit at B the coding is deciphered and that is the time that is entered on the clock at B. If the distance between the green bit and the red bit is L then the time difference will be L/C. Obviously by making L as small as possible the time diff is minimized.
In fig 1 I have the same arrangement as in fig 0 but it is now in a moving frame of reference (MFR) at 0.5C. The MFR is moving in the direction of the red arrow that has “direction” written on it :p.
At time zero the laser and the detector are located at positions A and B. At some time in the future they are located at positions C and D. A photon is emitted from the laser at time zero. It will follow the blue path as shown and strike the detector sometime in the future. As the encoded photon has traveled a fair distance the inaccuracy of the synchronization will be large and can be easily calculated. I will leave that to you and the first right answer gets an e_freddo.
In fig 2 again at time zero the laser and the detector are located at positions A and B. At some time in the future they are located at positions C and D. A photon is emitted from the laser at time zero. It will follow the blue path as shown and strike the detector sometime in the future. As the encoded photon has traveled only a short distance the inaccuracy of the synchronization will be small. If the distance between the green bit and the red bit is L then the time difference will be L/C. Obviously by making L as small as possible the time diff is minimized.
In a MFR why can't near perfect synchronization be achieved ?
The purpose of synchronizing clocks is so the time on one clock is as close a possible to the time on another clock. This can be achieved by any means possible to make the error as small as possible.
In Fig 0 the green bit is a laser that surprisingly emits photons. The red bit is a detector that detects the photons. Each emitted photon pulse is encoded with the exact time on it ie minute, second, milli sec, down to femto second say, using frequency modulation.
The clocks are synchronised by emitting the encoded photon from the green bit at A. When it strikes the red bit at B the coding is deciphered and that is the time that is entered on the clock at B. If the distance between the green bit and the red bit is L then the time difference will be L/C. Obviously by making L as small as possible the time diff is minimized.
In fig 1 I have the same arrangement as in fig 0 but it is now in a moving frame of reference (MFR) at 0.5C. The MFR is moving in the direction of the red arrow that has “direction” written on it :p.
At time zero the laser and the detector are located at positions A and B. At some time in the future they are located at positions C and D. A photon is emitted from the laser at time zero. It will follow the blue path as shown and strike the detector sometime in the future. As the encoded photon has traveled a fair distance the inaccuracy of the synchronization will be large and can be easily calculated. I will leave that to you and the first right answer gets an e_freddo.
In fig 2 again at time zero the laser and the detector are located at positions A and B. At some time in the future they are located at positions C and D. A photon is emitted from the laser at time zero. It will follow the blue path as shown and strike the detector sometime in the future. As the encoded photon has traveled only a short distance the inaccuracy of the synchronization will be small. If the distance between the green bit and the red bit is L then the time difference will be L/C. Obviously by making L as small as possible the time diff is minimized.
In a MFR why can't near perfect synchronization be achieved ?