Abstract
A proof of Bell’s theorem without inequalities is presented which exhibits three remarkable properties: (a) reduced local states are immune to collective decoherence; (b) distant local setups do not need to be aligned, since the required perfect correlations are achieved for any local rotation of the local setups; (c) local measurements require only individual measurements on the qubits. Indeed, it is shown that this proof is essentially the only one which fulfills (a), (b), and (c).
- Received 13 March 2003
DOI:https://doi.org/10.1103/PhysRevLett.91.230403
©2003 American Physical Society