Speaker: Dr. Juha Javanainen, University of Connecticut

Title: Bose-Einstein condensate in a double-well trap: back-action from measurements of atom numbers forces classical behavior.

Abstract: We consider a double-well trap containing a BEC, assuming that the numbers of the atoms on both sides of the trap are monitored continuously using light scattering. We develop both an exact quantum mechanical simulation, including back-action from detection of the scattered light, and a classical simulation by expanding the quantum theory as powers in the inverse of the total number of condensate atoms. In our numerical examples the quantum and classical descriptions give results so similar that in practice it would be impossible to tell them apart experimentally, even under circumstances when the standard mean-field theory of a condensate is expected to fail.