Tsirelson’s problem and an embedding theorem for groups arising from non-local games

  title={Tsirelson’s problem and an embedding theorem for groups arising from non-local games},
  author={William Slofstra},
  journal={Journal of the American Mathematical Society},
  • William Slofstra
  • Published 9 June 2016
  • Mathematics
  • Journal of the American Mathematical Society
Tsirelson’s problem asks whether the commuting operator model for two-party quantum correlations is equivalent to the tensor-product model. We give a negative answer to this question by showing that there are non-local games which have perfect commuting-operator strategies, but do not have perfect tensor-product strategies. The weak Tsirelson problem, which is known to be equivalent to the Connes embedding problem, remains open. The examples we construct are instances of (binary) linear system… 
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