The Shear Viscosity to Entropy Ratio: A Status Report
By S. Cremonini. 2011
172 citations recorded by the source corpus.
This review highlights some of the lessons that the holographic gauge/gravity duality has taught us regarding the behavior of the shear viscosity to entropy density in strongly coupled field theories. The viscosity to entropy ratio has been shown to take on a very simple universal value in all gauge theories with an Einstein gravity dual. Here we describe the origin of this universal ratio, and focus on how it is modified by generic higher derivative corrections corresponding to curvature corrections on the gravity side of the duality. In particular, certain curvature corrections are known to push the viscosity to entropy ratio below its universal value. This disproves a longstanding conjecture that such a universal value represents a strict lower bound for any fluid in nature. We discuss the main developments that have led to insight into the violation of this bound, and consider whether the consistency of the theory is responsible for setting a fundamental lower bound on the viscosity to entropy ratio.
Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics, Statistical and Nonlinear Physics
View Paper: https://www.semanticscholar.org/paper/49e58320279515c9b8bea0adf6144a9e9e522e90
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Astronomy and Astrophysics
- M. Rangamani
- S. Hartnoll
- Felix M. Haehl
- V. Hubeny
- R. Loganayagam
- A. Adams
- T. Schaefer
- Lincoln D. Carr
In Nuclear and High Energy Physics
- M. Rangamani
- V. Hubeny
- S. Hartnoll
- Felix M. Haehl
- R. Loganayagam
- A. Adams
- T. Schaefer
- Lincoln D. Carr
In Statistical and Nonlinear Physics
- M. Rangamani
- Felix M. Haehl
- A. Adams
- T. Schaefer
- Lincoln D. Carr
- John E. Thomas
- P. Steinberg
- R. Loganayagam
Citations in the corpus
- Strongly correlated quantum fluids: ultracold quantum gases, quantum chromodynamic plasmas and holographic duality (2012, background): “‡ See [359] for a summary of the current state of such computations, and [237, 339] for a more detailed exposition of the computation we outline, and for references to the original literature.”
- Holographic Quantum Matter (2016, unknown): “We will be agnostic about the numerical prefactor in this and (most) other bounds [148].”
- Adiabatic hydrodynamics: the eightfold way to dissipation (2015, background): “It would be fascinating to develop this line of thought, for it should provide us with a geometric 104 We refer the reader to [100, 101] for critical discussions of this bound and survey of attempts to violate it in various systems.”
- Theory of universal incoherent metallic transport (2014, background): “Subsequent work found counterexamples to the original statement, but the powerful notion that a specific (to be discovered) C does exist such that (9) is always true has survived [12].”