Physical Review Letters

Violations of a simple inequality for classical fields

J. D. Franson

Published Jul 15, 1991• 54 citations

Abstract

It has been shown that two correlated photons incident upon two distant interferometers can give a coincidence counting rate that depends nonlocally on the sum of the phases of the two interferometers. It is shown here that the results of existing experiments violate a simple inequality that must be satisfied by any classical or semiclassical field theory. The inequality provides a graphic illustration of the lack of objective realism of the electric field.

DOI: 10.1103/physrevlett.67.290

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