Divergent series and hydrodynamics

Speaker and affiliation: 
Viktor Svensson (Szkoła Doktorska NCBJ)
Date: 
Thu, 2021-05-27 09:00 to 10:00
Venue: 
https://www.gotomeet.me/NCBJmeetings/phd-seminar
Abstract: 

Hydrodynamics is a very useful theory of near equilibrium dynamics, but it is far from obvious what "near equilibrium" means in practice. Central to the formulation of hydrodynamics is a perturbative series, the gradient expansion. The applicability of hydrodynamics should be related to how well this perturbative expansion works. Many studies have shown that it is actually a divergent series. In this seminar, I'll talk about why it diverges, and why this does not spell the end of hydrodynamics.