A novel formula for bulk viscosity from the null horizon focusing equation


DOI: 10.1007/JHEP06(2011)007

Cite this article as:
Eling, C. & Oz, Y. J. High Energ. Phys. (2011) 2011: 7. doi:10.1007/JHEP06(2011)007


The null horizon focusing equation is equivalent via the fluid/gravity correspondence to the entropy balance law of the fluid. Using this equation we derive a simple novel formula for the bulk viscosity of the fluid. The formula is expressed in terms of the dependence of scalar fields at the horizon on thermodynamic variables such as the entropy and charge densities. We apply the formula to three classes of gauge theory plasmas: non-conformal branes, perturbations of the \( \mathcal{N} = 4 \) supersymmetric Yang-Mills theory and holographic models of QCD, and discuss its range of applicability.


Black Holes Holography and quark-gluon plasmas Gauge-gravity correspondence 

Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  1. 1.SISSAVia Bonomea 265TriesteItaly
  2. 2.INFN Sezione di TriesteTriesteItaly
  3. 3.Raymond and Beverly Sackler School of Physics and AstronomyTel-Aviv UniversityTel-AvivIsrael