Quantum violation of stochastic noncontextual hidden-variable theories
Shasanka Mohan Roy, Virendra Singh
We formulate stochastic noncontextual hidden-variable theories. In such theories the hidden state \ensuremath{\lambda} specifies not definite values, but expectation values A\ifmmode\bar\else\textasciimacron\fi{}(\ensuremath{\lambda}), . . . of observables A, . . . and noncontextuality means that A\ifmmode\bar\else\textasciimacron\fi{}(\ensuremath{\lambda}) is independent of which other commuting observables commuting with A are measured together with A. We show via Bell inequalities that such theories conflict with quantum theory and propose a two-photon experimental test. We also show that for a single particle of spin (${2}^{\mathit{n}}$-1)/2, quantum violation of classical noncontextuality grows exponentially with n.
Physical Review A•Oct 1, 1993•21 citations