The effect of repulsive interactions on Bose-Einstein condensation

@article{Smedt1986TheEO,
  title={The effect of repulsive interactions on Bose-Einstein condensation},
  author={Philip de Smedt},
  journal={Journal of Statistical Physics},
  year={1986},
  volume={45},
  pages={201-213}
}
One-dimensional Bose gases that interact via a repulsive two-body interaction and show Bose-Einstein condensation at the free level are studied. It is shown that the introduction of this interaction, however small, destroys the condensate. It is also shown that the free energy of an interacting Bose gas does not depend on the boundary conditions(including attractive boundary conditions) in the van der Waals limit.