Abstract

The question we have been investigating is whether the nonlocality of standard quantum mechanics is the private domain of Nature, as is generally assumed by the physics community, or whether in special circumstances the nonlocal connection between subsystems can be used to send signals from one observer to another. With the aid of generous private contributions and some use of CENPA resources, we have continued the work on this test of nonlocal quantum communication, which has been reported in the past three years1�2�3. The initial configuration of the experiment, as described in the first two references, employed a high power argon-ion laser operating at about 1 W in the ultraviolet at 351 nm that pumped nonlinear crystals (BBO or LiIO3) to produce pairs of momentum-entangled 702 nm photons, on which measurements were subsequently performed. It was concluded that signal-to-noise limitations from fluoresence photons competing with the down-converted photons prevented the planned measurements using the initial configuration.