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arXiv · 0812.2521

Beyond eta/s = 1/4pi

Alex Buchel·Robert C. Myers·Aninda Sinha
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Abstract

We use low-energy effective description of gauge theory/string theory duality to argue that the Kovtun-Son-Starinets viscosity bound is generically violated in superconformal gauge theories with non-equal central charges $c\ne a$. We present new examples (of string theory constructions and of gauge theories) where the bound is violated in a controllable setting. We consider the comparison of results from AdS/CFT calculations to the QCD plasma in the context of this discussion.

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Alex Buchel, Robert C. Myers, Aninda Sinha. 2009-03-18. Beyond eta/s = 1/4pi. https://doi.org/10.1088/1126-6708%2F2009%2F03%2F084

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