Time Dilation in Rotating Bodies: Effects?

[Ian1108]

If a body spins fast enough does the outer portion experience time at a different rate than the inner and if so what effects might this have?

 

[yuiop]

If a body spins fast enough does the outer portion experience time at a different rate than the inner and if so what effects might this have?

Yes. Clocks on the outer portion tick slower than clocks at the inner. If we start with two synchronised clocks (A and B) at the centre and transport A to the outer edge and at a later time transport B to the outer edge, then all else being equal, less time will have elapsed on clock A than on clock B when they are side by side again on the outer edge.

If we have an inertial clock outside the rim of the disc that is at rest with centre of the disc, then this clock will appear to be ticking slower from a point of view of an observer that is on the rim of the disk as the rotating observer passes the the non-rotating clock and vice versa just as in Special Relativity, but after a complete revolution of the disc both observers will agree that less time has elapsed on the clock that is rotating with the disc than on the clock that is outside the disc, when they are alongside each other again. Because acceleration is involved, differences in elapsed times are absolute.