QLunch:The Dilute Limit of Interacting Bose Gases

Speaker: Jan Philip Solovej from QMATH

Title: The Dilute Limit of Interacting Bose Gases

Abstract: I will discuss the interacting many-body Bose gas and, in particular, recent progress in understanding the asymptotics of the ground state energy in the dilute limit.The ground state energy of two bosons confined to a large box can be expressed in terms of the zero energy scattering length of the interacting potential. It has been generally believed that the ground state energy density in the dilute limit for a thermodynamic Bose gas has a two term asymptotic expansion which is universal in the sense that the terms still depend only on the scattering length of the interaction potential.The asymptotics was originally proposed by Lee, Huang, and Yang in 1957 for the hard core gas and the asymptotics goes by the name of the Lee-Huang-Yang formula. It has been extensively studied in mathematical physics ever since. I will discuss recent work with S. Fournais that establishes the universal validity of the formula.