From: eripe.dk@gmail.com   
      
   On Thursday, May 4, 2017 at 4:53:54 AM UTC+7, 0something0 wrote:   
   > like, what does all the letters stand for in the diagram?   
      
   Those are the reference frames for two different observers.   
      
   x is the space coordinate and ct is the time coordinate for ship_1 moving at   
   1/3c. He then does FTL from O to A. Then he does a U-turn to go 1/3c the other   
   way.   
   By chainging his speed he changes his reference frame, so now he is in x' and   
   ct'   
      
   Then he does FTL back to O, and arrives before he left.   
      
   The Minkowski diagram is explained pretty good in the two videos I posted   
   above.   
      
   --- SoupGate-Win32 v1.05   
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