From: fortunati.luigi@gmail.com   
      
   Luigi Fortunati gioved=EC 26/05/2022 alle ore 12:47:45 ha scritto:   
   >> Richard Livingston marted=EC 24/05/2022 alle ore 18:05:03 ha scritto:   
   >>>> For example, if I put two clocks at the maximum distance on the floor,   
   >>>> they remain synchronized and, therefore, horizontally there is no   
   >>>> acceleration (there is quiet).   
   >>>>   
   >>>> If, on the other hand, I put a clock on the floor and one on the   
   >>>> ceiling, they don't stay synchronized and, therefore, there is   
   >>>> acceleration vertically (there is no quiet).   
   >>>   
   >>> According to GR, yes.   
   >>>   
   >>> Rich L.   
   >>   
   >> In the free-falling elevator, does the clock on the floor stay   
   >> synchronized with the clock on its ceiling?   
   >>   
   >> Luigi   
   >>   
   >> [[Mod. note -- Yes, apart from tidal effects.  -- jt]]   
   >   
   > This is exactly the point!   
   >   
   > Do the clocks on the floor of the free-falling elevator stay   
   > synchronized with those on the ceiling in the presence of the tides or   
   > not?   
   >   
   > [[Mod. note -- The short non-mathematical answer is that the clocks in   
   > (at rest with respect to) the free-falling elevator stay synchronized   
   > to within a tidal-field tolerance.   
      
   If we accept the criterion of "tolerance", then also the clock at the   
   top of the tower remains synchronized with the one at the base (within   
   the limits of the tolerance) but this is not the case because, after a   
   sufficiently long time, due to the tidal force (which there is also   
   here) the clock at the base of the tower is further behind than the one   
   at the top.   
      
   So the tower (like the lift stopped at the floor) is not an inertial   
   reference frame and, therefore, it is an accelerated reference frame.   
      
   And if the Tower were to plummet downward like the free-falling   
   elevator, would its clock at the top remain synchronized with the one   
   at the base even for a long enough time, or would one of the two   
   continue to lag behind the other?   
      
   [[Mod. note --   
   Your questions are all answered by the Taylor series explained in a   
   previous moderator's note.   
   -- jt]]   
      
   --- SoupGate-Win32 v1.05   
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