From: psperson@old.netcom.invalid   
      
   On 4 Feb 2026 13:31:48 GMT, ram@zedat.fu-berlin.de (Stefan Ram) wrote:   
      
   >quadi  wrote or quoted:   
   >>Of course, though, the Ptolemaic geocentric solar system is not disproved    
   >>by this.   
   >   
   >  Basically, all coordinate systems are on equal footing as long   
   >  as you can link them with diffeomorphisms. So yeah, you can   
   >  pick a system where Earth always has the coordinates (0,0,0),   
   >  meaning it's "at rest", but you can't use one where Earth is   
   >  flat, since there's no diffeomorphism that turns a sphere into   
   >  a plane or a surface built from one.   
      
   You guys do realize that /Ptolemy/ showed the Earth was round (just   
   immobile and at the center of everything) by pointing out that the   
   "horizon" would have no meaning on a Flat Earth: the fixed stars are   
   so far away that they would /all/ be visible regardless of lattittude,   
   right?   
   --    
   "Here lies the Tuscan poet Aretino,   
   Who evil spoke of everyone but God,   
   Giving as his excuse, 'I never knew him.'"   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)