# Mathematics PDE and Analysis Seminar - Chun Shen

This event is in the past.

**Date:**February 19, 2020

**Time:**2:30 p.m. - 3:30 p.m.

**Category:**Seminar

Speaker: **Chun Shen, Department of Physics and Astronomy, Wayne State University**

Title: **Fluid dynamic applications in relativistic heavy-ion collisions**

Abstract: **In this talk, I will first introduce the remarkable success in applying fluid dynamics to model the evolution of relativistic heavy-ion collisions in high energy nuclear physics. Relativistic Navier-Stokes equation violates causality and is numerically unstable. I will discuss the Israel-Stewart theory, which cured these two problems in the relativistic regime. The validity of fluid dynamics usually relies on a large separation between the system's macroscopic scale and microscopic mean free path. Surprisingly, fluid dynamics simulations can predict flow observables in small collision systems very well, in which there is no distinct scale separation. This result has lead to the modern formulation of fluid dynamics in out-of-equilibrium situations. Considering fluid dynamics as a series of gradient expansion, I will highlight recent developments of resummations in this series and its related attractor solutions in some simplified cases with high degrees of symmetry. **