Hidden variables and the two theorems of John Bell

  title={Hidden variables and the two theorems of John Bell},
  author={N. David Mermin},
  journal={Reviews of Modern Physics},
  • N. Mermin
  • Published 1 July 1993
  • Physics
  • Reviews of Modern Physics
Although skeptical of the prohibitive power of no-hidden-variables theorems, John Bell was himself responsible for the two most important ones. I describe some recent versions of the lesser known of the two (familiar to experts as the "Kochen-Specker theorem") which have transparently simple proofs. One of the new versions can be converted without additional analysis into a powerful form of the very much better known "Bell's Theorem," thereby clarifying the conceptual link between these two… 

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