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Never heard of that Bill.
Somewhere, I no longer remember where, I read that QM requires a universal time that could be synchronized across the Universe.Is this right? If so, why?
Quote from: Colin Never heard of that Bill.I seem to remember that in another "universe" it was you who said Pete was my best bet for an answer on that one. 
Lightarrow, can that be taken as saying that originally QT had a universal time, but later "incarnations" introduced a relative aspect to time, so that there is no longer a universal time requirement?
Space and timeIn classical mechanics and non-relativistic QM, time is an absolute quantity: all observers and particles can always agree on, "ticking away" in the background independent of space. Thus in non-relativistic QM one has for a many particle system ψ(r1, r2, r3, ..., t, σ1, σ2, σ3...).In relativistic mechanics, the spatial coordinates and coordinate time are not absolute; any two observers moving relative to each other can measure different locations and times of events. The position and time coordinates combine naturally into a four-dimensional spacetime position X = (ct, r) corresponding to events, and the energy and 3-momentum combine naturally into the four momentum P = (E/c, p) of a dynamic particle, as measured in some reference frame, change according to a Lorentz transformation as one measures in a different frame boosted and/or rotated relative the original frame in consideration. The derivative operators, and hence the energy and 3-momentum operators, are also non-invariant and change under Lorentz transformations.
That can't possibly mean that the same scenario calculated using relativistic and non-relativistic QM would give different answers, and that they would both be right; or can it?