I agree with your approach, and I see many others here do to. I don't know if you've read Peter Jacksons essay 'Perfect Symmetry' yet, but if you look below the surface (and see the posts) I think you'll find the proof that you're right.
Phil
Peter,
RE: velocity. In my haste, I probably didn't frame that question very well and certainly not fully! What I was really getting at is that because it is a vector quantity, the preferred ordering is required to describe the *direction* as well as the rate of motion. The clock readings then must correlate with the order of points along the trajectory. I guess what you are saying is that there need not be any *tense* involved with the motion in the first place or therefore the clock readings and I can agree with that. In fact I believe that is exactly the sort of thinking we need!
I just feel we have created a problem with our use of clocks and the resulting standard time unit of the second which we have conventionally applied to all measurements, thereby introducing our own external, absolute time (albeit based on physical processes). This is where the preferred ordering of readings is interpreted as "time direction" and why I said it is required in current physics. For a fully relational (Machian?) model, I feel we should be representing these things more as purely physical relations between objects/variables in the system of interest. I don't know how to do this whilst "preserving" the sense of trajectory, particularly in the case of acceleration, but maybe much smarter people, perhaps Carlo Rovelli or yourself, can succeed!
Cheers
Dear Roy,
I learned from physiology that the only non-arbitrary reference for measuring time as well as for naturally describing a process in real time is the very moment. We need not more and not less than to choose this point of view instead the birth of Christ at midnight in Greenwich.
Regards,
Eckard
