Possibility of realizing Bussey's thought experiment on collapse of the wave function at the microscopic level

Abstract

We discuss on feasibility of experiments to test if the wave function collapses at the level of microscopic events. The original idea is Bussey's 'thought' experiment introduced in 1984. Bussey's proposal is to collide two particles and then two pairs of scattered and unscattered waves of each particle are examined by a pair of Mach-Zehnder type interferometers (MZI). Different coincidence rates between different sets of combinations of MZI outputs are expected depending on the collapse/non collapse assumption. In our proposition to realize this idea, a pair of low-energy electron beams is collided nearly head-on in a nanometer-size region. Then each combination of two waves scattered at small angles is thrown into the MZI. Each MZI is composed of Moellenstedt biprisms as two arms and mirrors, and then brought together at single crystal films which act as half reflecting mirrors (beam splitters). Coincidence counting is done among four outputs of the beam splitters. Another method to measure the position correlation after the biprisms is also proposed.