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atyy

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I just meant that each frame has its own coordinate time, and each worldline has its own proper time. So in relativity, we have many different things called "time". It seems to me that the theory is needed for that, not the "data" alone, whatever that may be. I guess time is a concept, or many different concepts, so it must be determined by the theory.With respect to "preferred time" do you mean direction? I do not want to answer that presumptuously as I can relate it to too many concepts. However, I do not know in what way I said you do not need "theory to define time". I said that the legitimacy of theory is predicated on and justified by the empirical data, not the other way around. Without which it is nothing more that philosophy. And that this empirical data, as it relates to time, was in fact the result of counting discrete events. The fact that we need a theory for operational consistency does not raise theory above the empirical constraints it is predicated on.

If all you have are events, how do you order them? Isn't it conceivable that events may not be ordered at all? Do you allow that time could be like space, whose points can't be ordered on a line (http://arxiv.org/abs/hep-th/0008164" [Broken])? Or is every possible order a possible time (which is what proper time is, with the restriction to timelike orderings)? Also, if spacetime is continuous, and all we have are continuous fields on the manifold, how do you "count" events?My initial statement, which has been taken issue with, is that time can consistently be viewed in terms of event counts. A bit simple, but fully defensible empirically. When Einstein said "time is what we measure" it was simplistic also. My statement merely boils down to defining "what we measure", and that is discrete series of events. Theoretically it works whether it comes in discrete steps or not, but the fact remain: We measure discrete series of events.

I came across an interesting "[url[/URL]: "The question of the validity of the presuppositions of geometry in the infinitely small hangs together with the question of the inner ground of the metric relationships of space. In connection with the latter question... the above remark applies, that for a discrete manifold, the principle of its metric relationships is already contained in the concept of the manifold itself, whereas for a continuous manifold, it must come from somewhere else. Therefore, either the reality which underlies physical space must form a discrete manifold or else the basis of its metric relationships should be sought for outside it[...].

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