2 papers
math.PR2026
The free energy of the interacting Bose gas: a variational description with loops and interlacements
Wolfgang König
We consider the interacting Bose gas in the thermodynamic limit in a large box in at positive temperature with particle density . We…
math.PR2025
Off-diagonal long-range order for the free Bose gas via the Feynman--Kac formula
Wolfgang König, Quirin Vogel, Alexander Zass
We consider the path-integral representation of the ideal Bose gas under various boundary conditions. We show that Bose--Einstein condensation occurs at the famous critical density…