Edgar, The structure of Minkowski spacetime is explained here http://en.wikipedia.org/wiki/Minkowski_space Once one decides on a coordinate system, every point can be assigned a unique x,y,z,t position. Hence the meeting of two observers to compare clocks can be assigned a unique x,y,z,t position. Their clocks will differ according to the paths they took through space-time to reach the meeting point.
According to SR that is all you need to know. If you want to add anything more you need to explain why it's important - what physical difference it makes. Of course a cellular automaton or similar quantisation of space-time, as required for a computational theory of reality, rquires an absolute rest frame and a synchronised clock. Personally, although I find such theories attractive, I have long regarded this as a problem with them, which in my opinion they have not yet adequately addressed (although placing the cells on the light come might work, in Minkowski space - but somehow I doubt it). -- 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 everything-list+unsubscr...@googlegroups.com. To post to this group, send email to email@example.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.