New Approach to Bose Condensation and Superfluidity in (4)He

摘要

An investigation is made of the implications that the presence of a Bosecondensate (BC) has for the form of the many particle Schroedinger wavefunction. It is shown that many particle wavefunctions of states which contribute to the BC, contain long range structure in the position space of each particle. It follows from the requirement that the wavefunction is single valued that, in the presence of a BC, the angular momentum of each particle must be quantized over macroscopic length scales. The paper thus provides a new and simple proof from first principles, that Bose condensation implies macroscopic quantum behavior. It is shown that this behavior can be described in terms of the occupation by each particle of the smae single particle-like macroscopic wavefunction. The structure in position space of this wavefunction is investigated, using a well known model of the many particle wavefunction for the ground state of 4He.