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arXiv · 0903.3244

Higher derivative effects on eta/s at finite chemical potential

Sera Cremonini·Kentaro Hanaki·James T. Liu·Phillip Szepietowski
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Abstract

We examine the effects of higher derivative corrections on eta/s, the ratio of shear viscosity to entropy density, in the case of a finite R-charge chemical potential. In particular, we work in the framework of five-dimensional N =2 gauged supergravity, and include terms up to four derivatives, representing the supersymmetric completion of the Chern-Simons term A \wedge Tr (R \wedge R). The addition of the four-derivative terms yields a correction which is a 1/N effect, and in general gives rise to a violation of the eta/s bound. Furthermore, we find that, once the bound is violated, turning on the chemical potential only leads to an even larger violation of the bound.

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Sera Cremonini, Kentaro Hanaki, James T. Liu, Phillip Szepietowski. 2009-05-05. Higher derivative effects on eta/s at finite chemical potential. https://doi.org/10.1103/physrevd.80.025002

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