On Sat, Mar 8, 2014 at 3:11 PM, Edgar L. Owen <[email protected]> wrote:
> Jesse, > > PS: And in your nice long numerical example, which I thank you for, it > seems to me what you are doing is calculating the proper time length of > every segment of A's trip in terms of C's proper time. Isn't that correct? > No, it's in terms of coordinate time in C's rest frame. "C's proper time" can only be defined between pairs of events on C's own worldline. Of course if C is inertial as in this example, then the coordinate time of events on C's worldline is the same as the proper time between those events, but it doesn't make sense to talk about "C's proper time" between events that are NOT on C's worldline. > > But if so aren't you in fact establishing a 1:1 correlation of proper > times between A and C with your method? > > And isn't that what you keep telling me CAN'T BE DONE? > You can of course define a correlation in proper times of separated clocks A and B if you specify what frame's definition of simultaneity you want to use. Then you can find a pair of events a1 and b1 that are simultaneous in this frame, and a pair of events a2 and b2 that are simultaneous in this frame, and compare the proper time on A's worldline between a1 and a2 with the proper time on B's worldline between b1 and b2. But this sort of correlation will differ depending on what frame you choose (because the simultaneous events will differ), and what can't be done is find any basis in relativity for saying that one frame's correlation represents the "real" correlation while other frames' do not. Jesse -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
