The status of the KSS bound and its possible violations (How perfect can a fluid be?)
نویسندگان
چکیده
In this work we briefly review the Kovtun-Son-Starinet (KSS) computation of the ratio η/s for quantum field theories with gravitational dual and the related conjecture that it is bound from below by 1/4π . We discuss the validity of the bound and the nature of its possible violations, its relevance for RHIC, its connection with phase transitions and other related issues.
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