Abstract

The experiment of Ou et al [ 1 ] has established the Einstein-Podolsky-Rosen paradox in a situation where the relevant measured observables correspond to a photon number which is macroscopic. The paradox may still be achieved in this situation even though the inaccuracy of the photon number measurement may itself be a very large photon number. This experiment leads naturally to the introduction of the concept of “macroscopic local realism”, a basic premise used in all classical theories describing macroscopic measurements made on macroscopic systems. We show that the Einstein- Podolksky-Rosen argument as applied to the Ou et al. experiment uses the premise of macroscopic local realism to imply that quantum mechanics is incomplete. This is a stronger statement than the original paradox, since logically we must conclude from the arguement that we either reject macroscopic local realism (a weaker premise than local realism at all levels), or accept that quantum mechanics is incomplete. This result motivates us to question the validity of local realism at levels more macroscopic than those considered so far in the Bell-inequality experiments. We wish to test directly the predictions of macroscopic local realism against those of quantum mechanics.

© 1996 Optical Society of America