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449
From AdS/CFT correspondence to hydrodynamics
 J. High Energy Phys
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Viscosity in strongly interacting quantum field theories from black hole physics
, 2004
"... The ratio of shear viscosity to volume density of entropy can be used to characterize how close a given fluid is to being perfect. Using string theory methods, we show that this ratio is equal to a universal value of �/4πkB for a large class of strongly interacting quantum field theories whose dual ..."
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Cited by 170 (4 self)
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The ratio of shear viscosity to volume density of entropy can be used to characterize how close a given fluid is to being perfect. Using string theory methods, we show that this ratio is equal to a universal value of �/4πkB for a large class of strongly interacting quantum field theories whose dual description involves black holes in anti–de Sitter space. We provide evidence that this value may serve as a lower bound for a wide class of systems, thus suggesting that black hole horizons are dual to the most ideal fluids.
An exact theory of nonlinear waves on a lagrangianmean flow
 J. Fluid Mech
, 1978
"... An exact and very general Lagrangianmean description of the back effect of oscillatory disturbances upon the mean state is given. The basic formalism applies to any problem whose governing equations are given in the usual Eulerian form, and irrespective of whether spatial, temporal, ensemble, or ‘t ..."
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Cited by 88 (3 self)
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An exact and very general Lagrangianmean description of the back effect of oscillatory disturbances upon the mean state is given. The basic formalism applies to any problem whose governing equations are given in the usual Eulerian form, and irrespective of whether spatial, temporal, ensemble, or ‘twotiming ’ averages are appropriate. The generalized Lagrangianmean velocity cannot be defined exactly as the ‘mean following a single fluid particle’, but in cases where spatial averages are taken can easily be visualized, for instance, as the motion of the centre of mass of a tube of fluid particles which lay along the direction of averaging in a hypothetical initial state of no disturbance. The equations for the Lagrangianmean flow are more useful than their Eulerianmoan counterparts in significant respects, for instance in explicitly representing the effect upon meanflow evolution of wave dissipation or forcing. Applications to irrotational acoustic or water waves, and to astrogeophysical problems of waves on axisymmetric mean flows are discussed. In the latter context the equations embody generalizations of the EliassenPalm and CharneyDrazin theorems showing the effects on the mean flow of departures from steady, conservative waves, for arbitrary, finiteamplitude disturbances to a stratified, rotating fluid, with allowance for selfgravitation as well as for an external gravitational field. The equations show generally how the pseudomomentum (or wave ‘momentum ’) enters problems of meanflow evolution. They also indicate the extent to which the net effect of the waves on the mean flow can be described by a ‘radiation stress’, and provide a general framework for explaining the asymmetry of radiationstress tensors along the lines proposed by Jones (1973).
The phase transition between caged black holes and black strings: A review
, 2004
"... We now have two examples for the breakdown of black hole uniqueness in higher dimensional General Relativity: the blackhole blackstring transition and the rotating black ring. In the last few years the phase diagram of the former was the subject of considerable study. The most surprising results ..."
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Cited by 74 (9 self)
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We now have two examples for the breakdown of black hole uniqueness in higher dimensional General Relativity: the blackhole blackstring transition and the rotating black ring. In the last few years the phase diagram of the former was the subject of considerable study. The most surprising results seem to be the appearance of critical dimensions where the qualitative behavior of the system changes, and a novel kind of topology change. Recently, a full phase diagram was determined numerically, confirming earlier predictions for a merger point and giving very strong evidence that the endstate of the GregoryLaflamme instability is a black hole (in low enough dimensions). Here this progress is reviewed, illustrated with figures, put into a wider context, and the still open
Analogue Gravity
 Living Rev. Rel
"... Analogue models of (and for) gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particu ..."
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Cited by 66 (23 self)
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Analogue models of (and for) gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing) and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem
Particle acceleration at astrophysical shocks: A theory of cosmic ray origin’, Phys
 Rep
, 1987
"... 2. Observational background 4 4.3. Steadystate solution with scattering 29 2.1. Earth’s bow shock 4 4.4. Time dependence 34 ..."
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Cited by 49 (0 self)
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2. Observational background 4 4.3. Steadystate solution with scattering 29 2.1. Earth’s bow shock 4 4.4. Time dependence 34
Linearized pipe flow to Reynolds number 10^7
, 2003
"... A Fourier–Chebyshev Petrov–Galerkin spectral method is described for highaccuracy computation of linearized dynamics for flow in an infinite circular pipe. Our code is unusual in being based on solenoidal velocity variables and in being written in MATLAB. Systematic studies are presented of the dep ..."
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Cited by 27 (1 self)
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A Fourier–Chebyshev Petrov–Galerkin spectral method is described for highaccuracy computation of linearized dynamics for flow in an infinite circular pipe. Our code is unusual in being based on solenoidal velocity variables and in being written in MATLAB. Systematic studies are presented of the dependence of eigenvalues, transient growth factors, and other quantities on the axial and azimuthal wave numbers and the Reynolds number R for R ranging from 10 2 to the idealized (physically unrealizable) value 10 7. Implications for transition to turbulence are considered in the light of recent theoretical results of S.J. Chapman.
Wetting and spreading
, 2009
"... Wetting phenomena are ubiquitous in nature and technology. A solid substrate exposed to the environment is almost invariably covered by a layer of fluid material. In this review, the surface forces that lead to wetting are considered, and the equilibrium surface coverage of a substrate in contact wi ..."
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Cited by 26 (0 self)
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Wetting phenomena are ubiquitous in nature and technology. A solid substrate exposed to the environment is almost invariably covered by a layer of fluid material. In this review, the surface forces that lead to wetting are considered, and the equilibrium surface coverage of a substrate in contact with a drop of liquid. Depending on the nature of the surface forces involved, different scenarios for wetting phase transitions are possible; recent progress allows us to relate the critical exponents directly to the nature of the surface forces which lead to the different wetting scenarios. Thermal fluctuation effects, which can be greatly enhanced for wetting of geometrically or chemically structured substrates, and are much stronger in colloidal suspensions, modify the adsorption singularities. Macroscopic descriptions and microscopic theories have been developed to understand and predict wetting behavior relevant to microfluidics and nanofluidics applications. Then the dynamics of wetting is examined. A drop, placed on a substrate which it wets, spreads out to form a film. Conversely, a nonwetted substrate previously covered by a film dewets upon an appropriate change of system parameters. The hydrodynamics of both wetting and dewetting is influenced by the presence of the threephase contact line separating “wet ” regions from those that are either dry or covered by a microscopic film only. Recent theoretical, experimental, and numerical progress in the description of
Hydrodynamics of Rcharged black holes
, 2006
"... We consider hydrodynamics of N = 4 supersymmetric SU(Nc) YangMills plasma at a nonzero density of Rcharge. In the regime of large Nc and large ’t Hooft coupling the gravity dual description involves an asymptotically Anti de Sitter fivedimensional charged black hole solution of Behrnd, Cvetič an ..."
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Cited by 26 (1 self)
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We consider hydrodynamics of N = 4 supersymmetric SU(Nc) YangMills plasma at a nonzero density of Rcharge. In the regime of large Nc and large ’t Hooft coupling the gravity dual description involves an asymptotically Anti de Sitter fivedimensional charged black hole solution of Behrnd, Cvetič and Sabra. We compute the shear viscosity as a function of chemical potentials conjugated to the three U(1) ⊂ SO(6)R charges. The ratio of the shear viscosity to entropy density is independent of the chemical potentials and is equal to 1/4π. For a single charge black hole we also compute the thermal conductivity, and investigate the critical behavior of the transport coefficients near the boundary of thermodynamic stability.
Macroscopic polarization in crystalline dielectrics: the geometric phase approach
 Rev. Mod. Phys
, 1994
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