Extra QLunch: Théotime Girardot

Speaker: Théotime Girardot, GSSI, Italy

Title: Superfluidity of the dilute Bose gas at low temperature

Abstract: We present in this talk a derivation of the expression of the superfluidity fraction of a dilute Bose gas in a box beyond the Gross-Pitaevskii regime at low temperature and explain how it could be extended to the thermodynamic limit. The talk focus on the proof of a lower bound for the superfluidity fraction in the box which makes use of recent advances in the study of the dilute Bose gas at low temperature and allows us to identify the temperature depend normal (non superfluid) density.