Tuesday, December 8, 2015

experimental physics - How to determine the order of indications of a clock?


Given the description of a clock A, as





  • (1) a set A of all (more than 2) distinct indications of this clock, in no particular order
    (where the individual indications contained in set A are denoted below as "AJ", "AQ", "AV" etc.), together with




  • (2) a function tA:AR
    (such that we may speak of set A and function tA together as "a clock, A" at all),





and, in line with Einstein's assertion that:
"All our well-substantiated space-time propositions amount to the determination of space-time coincidences {such as} encounters between two or more {... participants}"
,
given



  • (3) a sufficient suitable account, in no particular order, of participants (such as A, J, or Q) and their encounters (where AJ is A's indication at the encounter of A and J, AQ is A's indication at the encounter of A and Q, and so on) --


How can the order of indications of clock A be derived?


Or to consider the simplest case:
How can be determined whether
AJ was between AQ and AV, or

AQ was between AV and AJ, or
AV was between AJ and AQ
?


Note:
It should not be assumed that clock A was "monotonous";
in other words: it is not an acceptable answer to argue
"if (tA[AV]tA[AQ])×(tA[AQ]tA[AJ])>0 then AQ was between AV and AJ".


Another note in response to a comment by Jim:
The encounters (coincidence events) in which the participant took part whose set of indications at those encounters is called A (and who is therefore him/her/itself conveniently called A as well) may be denoted as
"EAJ", "EAQ", "EAV",

among others;
corresponding to the indications "AJ", "AQ", "AV" of A (and, together with function tA, therefore indications of clock A) which had been named explicitly above.


As far as a Lorentzian manifold may be assigned to those events in which A took part (together with additional events, as may be required) and as far as the corresponding Causal structure would be determined, those events in which A took part were all elements of one chronological (or timelike) Curve.


My question is consequently, in other words, whether and how elements of such a chronological (or timelike) curve may be ordered, given their parametrization only by some arbitrary function tA:AR,
together, of course, with a sufficient suitable account (3, above) of all participants involved, and their encounters, if any, in no particular order.




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