Seminarium Optyczne

While the statistical properties of an ideal Bose gas are well understood, accounting for interaction induced corrections remains a challenging and unresolved problem. We propose a fundamentally different approach: instead of calculating partition functions, we construct models of the canonical and microcanonical ensembles directly. Previously, to this end, we developed two sampling techniques—one based on the classical field approximation and the other on Fock State Sampling (FSS). Each method offers significant advantages but also suffers from critical limitations: the classical field approach is plagued by ultraviolet divergence, while FSS neglects changes to the condensate wave function. In this talk, we introduce a new Hybrid Sampling method that overcomes these issues, combining the strengths of both earlier approaches while avoiding their respective shortcomings.