Title: Updates on Chiral plasma instabilities in gauge theory from lattice
Date: Dec 22, 2020
Time: 14:00 - 15:00
Speaker: Dr. Sayantan Sharma
Affiliation: Institute of Mathematical Sciences, Chennai, India
Abstract: In this talk I will discuss about the latest understanding on chiral plasma instabilities and the onset of chiral turbulence in Abelian plasmas far from equilibrium. By performing classical lattice simulations of the microscopic theory, we show that the generation of strong helical magnetic fields from a helicity imbalance in the fermion sector proceeds through three distinct steps. During the initial stages the helicity imbalance of the fermion sector causes an exponential growth of magnetic field modes with right handed polarization. Secondary growth of unstable modes accelerates the helicity transfer from fermions to gauge fields and ultimately leads to the emergence of a self-similar scaling regime characteristic of decaying turbulence, where magnetic helicity is efficiently transferred to macroscopic length scales. In the turbulent regime the evolution of magnetic helicity spectrum can be described by an infrared power-spectrum with spectral exponent $\kappa = 10.2\pm 0.5$, which we determine from our simulations. I will conclude by discussing some expectations about this phenomenon in non-Abelian gauge theories.