Aspects of holographic entanglement at finite temperature and chemical potential

Abstract:We apply the transformation of mixing azimuthal and internal coordinate or mixing time and internal coordinate to a stack of N black M-branes to find the Melvin spacetime of a stack of N black D-branes with magnetic or electric flux in string theory, after the Kaluza-Klein reduction. We slightly extend previous formulas to investigate the external magnetic and electric effects on the butterfly effect and holographic mutual information. It shows that the Melvin fields do not modify the scrambling time and will enhance the mutual information. In addition, we also T-dualize and twist a stack of N black D-branes to find a Melvin Universe supported by the flux of the NSNS b-field, which describes a non-comutative spacetime. It also shows that the spatial noncommutativity does not modify the scrambling time and will enhance the mutual information. We also study the corrected mutual information in the backreaction geometry due to the shock wave in our three model spacetimes.

Section: Jhep02(2017)032mentioning

confidence: 99%

Butterfly effect and holographic mutual information under external field and spatial noncommutativity

Huang

2017

“…The resulting quantity is thus finite. Following [27,28], let us now consider two separate limits: (i) u c u * and (ii) u c ∼ u * . Case (i), in which the geodesic stays mostly away from the infrared horizon, is equivalent to taking l/u * = l √ E 1.…”

Section: General Geodesicsmentioning

confidence: 99%

Emergent horizons and causal structures in holography

Banerjee

Kundu

2016

Self Cite

Abstract:The open string metric arises kinematically in studying fluctuations of open string degrees of freedom on a D-brane. An observer, living on a probe D-brane, can send signals through the spacetime by using such fluctuations on the probe, that propagate in accordance with a metric which is conformal to the open string metric. Event horizons can emerge in the open string metric when one considers a D-brane with an electric field on its worldvolume. Here, we emphasize the role of and investigate, in details, the causal structure of the resulting open string event horizon and demonstrate, among other things, its close similarities to an usual black hole event horizon in asymptotically AdS-spaces.To that end, we analyze relevant geodesics, Penrose diagrams and various causal holographic observables for a given open string metric. For analytical control, most of our calculations are performed in an asymptotically AdS 3 -background, however, we argue that the physics is qualitatively the same in higher dimensions. We also discuss how this open string metric arises from an underlying D-brane configuration in string theory.

“…Considering large entangling region limit, i.e., ρ h , the main contribution to the area of the minimal surface comes from the limit where it is extended all the way to the horizon, such that ρ t ∼ ρ h (see [35][36][37] for related analysis). In this limit by defining ρ = ρ t ξ, one finds…”

Section: Jhep10(2016)135mentioning

confidence: 99%

Non-local probes in holographic theories with momentum relaxation

Mozaffar

Mollabashi

Omidi

2016

We consider recently introduced solutions of Einstein gravity with minimally coupled massless scalars. The geometry is homogeneous, isotropic and asymptotically anti de-Sitter while the scalar fields have linear spatial-dependent profiles. The spatiallydependent marginal operators dual to scalar fields cause momentum dissipation in the deformed dual CFT. We study the effect of these marginal deformations on holographic entanglement measures and Wilson loop. We show that the structure of the universal terms of entanglement entropy for d > 2-dim deformed CFTs is corrected depending on the geometry of the entangling regions. In d = 2 case, the universal term is not corrected while momentum relaxation leads to a non-critical correction. We also show that decrease of the correlation length causes: the phase transition of holographic mutual information to happen at smaller separations and the confinement/deconfinement phase transition to take place at smaller critical lengths. The effective potential between point like external objects also gets corrected. We show that the strength of the corresponding force between these objects is an increasing function of the momentum relaxation parameter.