Holographic thermalization of charged operators

144

Using holography, we study the evolution of a spatially homogeneous, far from equilibrium, strongly coupled N = 4 supersymmetric Yang-Mills plasma with a non-zero charge density or a background magnetic field. This gauge theory problem corresponds, in the dual gravity description, to an initial value problem in Einstein-Maxwell theory with homogeneous but anisotropic initial conditions. We explore the dependence of the equilibration process on different aspects of the initial departure from equilibrium and, while controlling for these dependencies, examine how the equilibration dynamics are affected by the presence of a non-vanishing charge density or an external magnetic field. The equilibration dynamics are remarkably insensitive to the addition of even large chemical potentials or magnetic fields; the equilibration time is set primarily by the form of the initial departure from equilibrium. For initial deviations from equilibrium which are well localized in scale, we formulate a simple model for equilibration times which agrees quite well with our results.

Section: Jhep07(2015)116supporting

confidence: 53%

“…3 Previous work examining thermalization in plasmas with non-zero chemical potential (not involving numerical solutions of far from equilibrium geometries) includes refs. [35][36][37][38].…”

Section: Jhep07(2015)116mentioning

confidence: 99%

Far-from-equilibrium dynamics of a strongly coupled non-Abelian plasma with non-zero charge density or external magnetic field

Fuini

Yaffe

2015

144

“…Readers interested in the results only may want to skip this section. We employ the geodesic approximation as first shown in [18] and used first in asymptotically AdS Vaidya spacetime in [19,20] and subsequently in [22,[25][26][27]65] etc. The Wightman functions are approximated via,…”

Section: Geodesicsmentioning

confidence: 99%

“…to the geodesic of a charged particle accounted for by the introduction of a Lorentz force term [27].…”

Section: Introductionmentioning

confidence: 99%

Correlations far from equilibrium in charged strongly coupled fluids subjected to a strong magnetic field

Cartwright

Kaminski

2019

Within a holographic model, we calculate the time evolution of 2-point and 1point correlation functions (of selected operators) within a charged strongly coupled system of many particles. That system is thermalizing from an anisotropic initial charged state far from equilibrium towards equilibrium while subjected to a constant external magnetic field. One main result is that thermalization times for 2-point functions are significantly (approximately three times) larger than those of 1-point functions. Magnetic field and charge amplify this difference, generally increasing thermalization times. However, there is also a competition of scales between charge density, magnetic field, and initial anisotropy, which leads to an array of qualitative changes on the 2-and 1-point functions. There appears to be a strong effect of the medium on 2-point functions at early times, but approximately none at later times. At strong magnetic fields, an apparently universal thermalization time emerges, at which all 2-point functions appear to thermalize regardless of any other scale in the system. Hence, this time scale is referred to as saturation time scale. As extremality is approached in the purely charged case, 2-and 1-point functions appear to equilibrate at infinitely late time. We also compute 2-point functions of charged operators. Our results can be taken to model thermalization in heavy ion collisions, or thermalization in selected condensed matter systems.

“…Here, the prime denotes a derivative with respect to v. Equation (28) implies that J λ (ext) J λ(ext) = 0. Hence, the matter current, which sources the gauge field, is null which is permissible for a physical matter current (for related discussions, see [46]).…”

Section: Holographic Thermalization With Weyl Correctionsmentioning

confidence: 99%

Holographic thermalization with Weyl corrections

Dey

Mahapatra

Sarkar

2016

We consider holographic thermalization in the presence of a Weyl correction in five dimensional AdS space. We first obtain the Weyl corrected black brane solution perturbatively, up to first order in the coupling. The corresponding AdS-Vaidya like solution is then constructed. This is then used to numerically analyze the time dependence of the two point correlation functions and the expectation values of rectangular Wilson loops in the boundary field theory, and we discuss how the Weyl correction can modify the thermalization time scales in the dual field theory. In this context, the subtle interplay between the Weyl coupling constant and the chemical potential is studied in detail.