NULL TEST OF QUANTUM-MECHANICS USING 2-PHOTON DOWN-CONVERSION

A null test of quantum mechanics is proposed. It is based on an arrang ement in which a source sends two signals to two detectors. At each de tector one of two different quantities can be measured. If the source satisfies three conditions, all of which can be verified experimentall y, then, according to quantum mechanics, a particular outcome is forbi dden. This result follows only from the way in which quantum mechanics constructs probabilities, and does not involve any dynamics. Looking for this outcome is a test of quantum mechanics. It is shown how this test can be realized using two-photon down-conversion.