2010/11/30 by Sayan K. Chakrabarti, Shankhadeep Chakrabortty, Sachin Jain
Physics and Astronomy · #hep-th
paper · pdf · doi:10.1007/jhep02(2011)073
published as JHEP 1102:073,2011 · 23 pages, minor modification, Version published in JHEP
arxiv created 2011/02/17 · arxiv updated 2011/04/04
It was proposed in arXiv:1008.2944 that, for certain gauge theories with gravity duals, electrical conductivity at finite chemical potential is universal. Here we provide a general proof that, when matter stress tensor satisfies a compact constraint, electrical conductivity is universal. We further elaborate our result with several conformal as well as non-conformal gauge theories. We also discuss how boundary conductivity and universal conductivity of stretched horizon are related.