XPost: comp.theory, sci.math, comp.ai.philosophy   
   From: mikko.levanto@iki.fi   
      
   On 13/01/2026 16:34, olcott wrote:   
   > On 1/13/2026 8:23 AM, Tristan Wibberley wrote:   
   >> On 13/01/2026 09:11, Mikko wrote:   
   >>> An oracle machine may be   
   >>> able to determine the haltinf of all Turing machines but not of all   
   >>> oracle machines with the same oracle (or oracles) so it is not   
   >>> universal.   
   >>   
   >> What's the formal definition of "an oracle machine" ?   
   >>   
   >> I would have thought an oracle always halts because it's an oracle it   
   >> answers every question that has an answer with either "HasAnswer answer"   
   >> or "HasNoAnswer".   
   >>   
   >   
   > It seems outside of computer science and into fantasy.   
   > https://en.wikipedia.org/wiki/Oracle_machine   
      
   It is not outside of computer science. In partucular, the question   
   whether any oracle can be implemented is one of unsolved problems   
   of computer science.   
      
   --   
   Mikko   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)