English

Holographic bulk viscosity: GPR vs EO

High Energy Physics - Theory 2015-03-19 v1

Abstract

Recently Eling and Oz (EO) proposed a formula for the holographic bulk viscosity, in arXiv:1103.1657, derived from the null horizon focusing equation. This formula seems different from that obtained earlier by Gubser, Pufu and Rocha (GPR) in arXiv:0806.0407 calculated from the IR limit of the two-point function of the trace of the stress tensor. The two were shown to agree only for some simple scaling cases. We point out that the two formulae agree in two non-trivial holographic theories describing RG flows. The first is the strongly coupled N=2* gauge theory plasma. The second is the semi-phenomenological model of Improved Holographic QCD.

Keywords

Cite

@article{arxiv.1104.2058,
  title  = {Holographic bulk viscosity: GPR vs EO},
  author = {Alex Buchel and Umut Gursoy and Elias Kiritsis},
  journal= {arXiv preprint arXiv:1104.2058},
  year   = {2015}
}

Comments

21 pages, 2 figures

R2 v1 2026-06-21T17:52:35.433Z