Causality, Joint measurement and Tsirelson’s bound
نویسندگان
چکیده
Tsirelson showed that 2 √ 2 is the maximum value that CHSH expression can take for quantumcorrelations [B. S. Tsirelson Lett. Math. Phys. 4, (1980) 93]. This bound simply follows from the algebra of observables. Recently by exploiting the physical structure of quantum mechanics like unitarity and linearity, Buhrman and Massar [H. Buhrman and S. Massar Phys. Rev. A 72, (2005) 052103] have established that violation of Tsirelson’s bound in quantum mechanics will imply signalling. We prove the same with the help of realistic joint measurement in quantum mechanics and a Bell’s inequality which has been derived under the assumption of existence of joint measurement and no signalling condition.
منابع مشابه
Joint measurement of spin and Tsirelson’s bound
No signalling condition by itself does not answer the question why quantum-mechanics violates Bell’s inequality by not more than 2 √ 2. Recently Buhrman and Massar [1] have given the answer by using unitarity and linearity of quantum-mechanics. We provide a simple answer to the same with the help of realistic joint measurement in quantum mechanics and Bell’s inequality which has been derived un...
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