mangaroosh
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We seem to be talking at cross purposes here, probably because of the different interpretations associated with the term, RoS.harrylin said:I made the comparisons because absolute and relative simultaneity are not mutually exclusive, just as time zones and universal time aren't, and just as relative and absolute velocities aren't.
It appears as though reference is being made to an RoS in the Lorentz transform, which I am referring to as the relativity of time co-ordinates (RoTC RoS), for the sake of discussion; and for the sake of distinguishing between the LET interpretation and the Einsteinian. There also appears to be an RoS which refers to the simultaneity of physical events, which is distinct from, but related to, the RoS of the Lorentz transform.
When I say RoS of physical events, I mean that two events which are simultaneous in one rerference frame are not simultaneous in another. This is contrasted with absolute simultaneity where two events which are simultaneous in one reference frame, are simultaneous across all reference frames. This notion of RoS is incompatible with absolute simultaneity, because absolute simultaneity doesn't allow for the conditions which constitute RoS i.e. if events, absolutely, happened simultaneously ("at the same time") for all observers, then it isn't possible that they weren't simultaneous for specific, idividual observers.
From the discussions I have had, on here and elsewhere, together wth pretty much all of the information I have encountered on Einsteinian relativity, it appears as though Einsteinian relativity incorporates the notion of RoS of physical events (as clarified above), while Lorentzian relativity incorporates absolute simultaneity of physical events. Given that both use the Lorentz transform, it suggests that the RoS of physical events is not a consequence of the Lorentz transform, while the (RoTC) RoS is.
The (RoTC) RoS appears to be distinct from the RoS of physical events, because Lorentzian relativity incorporates one but not the other. The RoS of physical events is related to the (RoTC) RoS because the RoS of physical events is based on an interpretation of the (RoTC) RoS.
The point I am making, with reference to the interpretation of RoS, is that it appears as though the Einsteinian interpretation is being applied to the Lorentz transform, when arguably it isn't the case - a point I will try to make more clearly below, in response to the next paragraph.
Alternative interpretaions of RoS
You have, on occasion, alluded to possible alternative interpretations of RoS under Einsteinian relativity; as outlined above, I am not really familiar with any interpretation that could not be distinguished as the RoS of physical events, as outlined above.
Are there such interpretations that could not be distinguished in the manner I have done, in representing my understanding; that is, is there an Einsteinian interpretation of RoS that is entirely disimilar to what I refer to as (RoTC) RoS but which doesn't result in the RoS of physical events, and so would make it compatible with absolute simultaneity - as outlined above?
OK, if we re-state the question in the context of this point.harrylin said:Here I can't follow at all what you say... Lorentz called the relativity of time co-ordinates "local time" and later Einstein called it "RoS". And Einstein's descriptions were purely operational, without any implied metaphysics - he tried to eliminate metaphysics from physics.
Is RoS a consequence of the Lorentz transform, or is RoS the Einsteinian interpretation of the relativity of time co-ordinates, which are a consequence of the Lorentz transform? Did Lorentz refer to the RoTC as RoS?
The impression I get is that RoS is the Einsteinian interpretation, but because it has been the dominant interpretation for so long, it has become conflated with what I refer to - for the sole purpose of clarity of discussion - as the relativity of time co-ordinates. It appears as though the RoTC are a consequence of the Lorentz transform, but the Einsteinian interpretation isn't necessarily, given that there is an alternative, incompatible Lorentzian interpretation; pending any alternative interpretations.
That's precisely how I understand it; the issue lies in the assumptions about time, as represented by the term years.harrylin said:When you say that based on your time reckoning two distant events both happened about 100 years ago, and someone else who uses a reference system that is moving relative to yours says that the one event happened about 99 years ago, and the other about 101 years ago, that is what is called "relativity of simultaneity". It is what Lorentz and Poincare called "local time", and it is about physical events.
If we take the year to be measured by a clock: if the difference in the recorded years is due to the mechanics of one clock causing it to tick slower - for example, the photon in the relatively moving atomic clock having to travel a longer path between the point of emission and the point of detection, than my clock - then, while the time co-ordinates of the events may be recorded differently by each of us, it doesn't mean that the events weren't simultaneous for both of us; it just means that our clocks tick at different rates due to the mechanics of the clock.
Hopefully the distinction between (RoTC) RoS and RoS of physical evetns demonstrates that they are slighty different issues; such that RoS of physical events is incompatible with absolute simultaneity.harrylin said:That is wrong, for (again) the same reason as why the following sentence is wrong:
"absolute velocity is incompatible with relative velocity, because relative velocity implies that velocities are not absolute."
harrylin said:That is at the heart of Relativity of Simultaneity...
Here is again a famous illustration of independent reference systems:
http://www.bartleby.com/173/9.html
Now put clocks at the front and back of the train, as well as one in the middle of the train, next to you; and synchronize your clock with a clock that happens to be just next to it at the station at t=0 (so that at x=0 and t=0, also t'=0: the LT assumption). I hope that you understand that the distant clocks on the train cannot indicate the same times as clocks next to them at the station.

don't worry, I understand the above; the point was why do relatively moving clocks indicate different times? The thought experiments usually highlight the fact that one clock ticks more slowly than the other i.e. they tick at different rates.
You have indeed alluded to it, however, I wouldn't necessarily say that it has been explained.harrylin said:In several recent threads this was discussed and explained that it's just one of several interpretations.
What are the interpretations of RoS that is compatible with absolute simultaneity (and presentism) that isn't, essentially, the same as the RoTC outlined above?
Would you, by any chance, know where I could read up on them?