From: julio@diegidio.name   
      
   On Monday, 24 July 2023 at 09:06:24 UTC+2, Stefan Ram wrote:   
      
   > The length of each of these world lines, measured in the   
   > metric of spacetime, gives the the time that has passed for each   
   > of them.   
      
   No, it gives the time *it takes* to each of them, whence they do not in   
   fact get to the "rendez-vous" point at the same time, the travelling   
   twin getting there "earlier" and meeting *a future (along their worldline,   
   whence older) version of* the twin that stayed, and, conversely, the twin   
   that stayed getting there "later" and meeting *a past (whence younger)   
   version of* the twin that travelled.   
      
   And I understand that that is not "orthodox", but please let me propose   
   that it is the correct reading of Einsteinian Relativity, under the notion   
   of "proper time" as "locally universal" time, together with the "clock   
   postulate", i.e. that all working clocks indeed tick at the same rate (the   
   proper time rate) in their own frame of reference.   
      
   Julio   
      
   --- SoupGate-Win32 v1.05   
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