Nonlinear chiral transport phenomena and holography: From gradient expansion to gradient resummation

by Tuna Demircik

at Particles and Fields Seminar

Mon, 17 Dec 2018, 14:00
Physics building (#54) room 207

Abstract

Nonlinear transport phenomena induced by the chiral anomaly are explored within a 4D field theory defined holographically as U 1 V x U 1 A Maxwell Chern Simons theory in Schwarzschild AdS 5 The present study goes along two complementary directions In the first part 1 in presence of external electromagnetic fields a general form of vector and axial currents is derived Within the gradient expansion up to third order we analytically compute all over 50 transport coefficients A wealth of new phenomena beyond the Chiral Magnetic and Chiral Separation Effects are discovered Particularly the charge diffusion constant and dispersion relation of Chiral Magnetic Wave are found to receive anomaly induced non linear corrections due to e m background fields Furthermore there emerges a new gapless mode which we refer to as Chiral Hall Density Wave propagating along the background Poynting vector In the second part 2 gradient resummation is performed for nonlinear chiral transports to restore causality In presence of weak constant background electromagnetic fields the constitutive relations for vector and axial currents resummed to all orders in the gradients of charge densities are encoded in nine momenta dependent transport coefficient functions TCFs These TCFs are first calculated analytically up to third order in gradient expansion and then evaluated numerically beyond the hydrodynamic limit Fourier transformed the TCFs become memory functions The memory function of the chiral magnetic effect CME is found to differ dramatically from the instantaneous response form of the original CME Beyond hydrodynamic limit and when external magnetic field is larger than some critical value the chiral magnetic wave CMW is discovered to possess a discrete spectrum of non dissipative modes 1 arXiv:1807 08467 2 arXiv:1807 11908

Created on 10-12-2018 by Bar Lev, Yevgeny (ybarlev)
Updaded on 10-12-2018 by Bar Lev, Yevgeny (ybarlev)