Exact Results in Quantum Theory

Main results derived in a recent study of an interacting Bose gas within the Hartree–Fock approximation will be discussed. The Kac scaling of the pair potential is used to show that• Bose–Einstein condensation can be destroyed by sufficiently long-range weak repulsive interactions• Bose–Einstein condensation occurs when the range of the binary potential is not too large• For a given potential there exists a critical temperature beyond which BE condensation is not possibleAt the end of the seminar, some challenging open problems will be presented.