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We use top-down gauge theory/string theory correspondence to compute relaxation rates in strongly coupled nonconformal gauge theory plasma. We compare models with difference mechanisms of breaking the scale invariance: "hard breaking" (by relevant operators) and "soft breaking" (by marginal operators). We find that the thermalization time of the transverse traceless fluctuations of the stress-energy tensor is rather insensitive to the mechanisms of breaking the scale invariance over a large range of the scale-breaking parameter d=1/3-c²s. We comment on the relevance of the results to QCD quark-gluon plasma. [ABSTRACT FROM AUTHOR]

We consider the dynamics of a spherically symmetric massless scalar field coupled to general relativity in anti-de Sitter spacetime in the small-amplitude limit. Within the context of our previously developed two time framework (TTF) to study the leading self-gravitating effects, we demonstrate the existence of two new conserved quantities in addition to the known total energy E of the modes: The particle number N and Hamiltonian H of our TTF system. Simultaneous conservation of E and N implies that weakly turbulent processes undergo dual cascades (direct cascade of E and inverse cascade of N or vice versa). This partially explains the observed dynamics of 2-mode initial data. In addition, conservation of E and N limits the region of phase space that can be explored within the TTF approximation and, in particular, rules out equipartition of energy among the modes for general initial data. Finally, we discuss the possible effects of conservation of N and E on late time dynamics. [ABSTRACT FROM AUTHOR]

Solutions with anti-D3 branes in a Klebanov-Strassler geometry with positive charge dissolved in fluxes have a certain singularity corresponding to a diverging energy density of the Ramond-Ramond and Neveu-Schwarz-Neveu-Schwarz three-form fluxes. There are many hopes and arguments for and against this singularity, and we attempt to settle the issue by examining whether this singularity can be cloaked by a regular event horizon. This is equivalent to the existence of asymptotically Klebanov-Tseytlin or Klebanov-Strassler black holes whose charge measured at the horizon has the opposite sign to the asymptotic charge. We find that no such Klebanov-Tseytlin solution exists. Furthermore, for a large class of Klebanov-Strassler black holes we considered, the charge at the horizon must also have the same sign as the asymptotic charge and is completely determined by the temperature, the number of fractional branes and the gaugino masses of the dual gauge theory. Our result suggests that antibrane singularities in backgrounds with charge in the fluxes are unphysical, which in turn raises the question as to whether antibranes can be used to uplift anti-de Sitter vacua to deSitter ones. Our results also point to a possible instability mechanism for the antibranes. [ABSTRACT FROM AUTHOR]

Recently, studies of the gravitational collapse of a scalar field within spherically symmetric anti-de Sitter (AdS) spacetimes presented by Bizon and Rostroworoski [Phys. Rev. Lett. 107, 031102 (2011)], Jalrnuzna et al. [Phys. Rev. D 84, 085021 (2011).] showed an instability of pure AdS to black hole formation. In particular, the work showed that arbitrarily small initial configurations of a scalar field evolved through some number of reflections off the AdS boundary untill a black hole forms. We consider this same system, extended to include a complex scalar field, and reproduce this phenomena. We present tests of our numerical code that demonstrate convergence and consistency. We study the properties of the evolution as the scalar pulse becomes more compact by examining the asymptotic behavior of the scalar field, an observable in the corresponding boundary conformal field theory. We demonstrate that such black hole formation occurs even when one places a reflecting boundary at finite radius, indicating that the sharpening is a property of gravity in a bounded domain and not of AdS itself. We examine how the initial energy is transferred to higher frequencies-which leads to black hole formation-and uncover interesting features of this transfer. [ABSTRACT FROM AUTHOR]

Motivated by gauge theory/string theory correspondence, a lower bound on the bulk viscosity of strongly coupled gauge theory plasma was proposed in [A. Buchel, Phys. Lett. B 663, 286 (2008).]. We consider strongly coupled N = 4 supersymmetric Yang-Mills plasma compactified on a two-manifold of constant curvature &bgr;. We show that the effective (1 + 1)-dimensional hydrodynamic description of the system is governed by the bulk viscosity violating the bound of [A. Büchel, Phys. Lett. B 663, 286 (2008).], once &bgr; < 0. [ABSTRACT FROM AUTHOR]

We use gauge theory/string theory correspondence to study finite temperature critical behavior of mass- deformed N = 4 SU(N) supersymmetric Yang-Mills theory at strong coupling, also known as N = 2* gauge theory. For a certain range of the mass parameters, N = 2* plasma undergoes a second-order phase transition. We compute all the static critical exponents of the model and demonstrate that the transition is of the mean-field theory type. We show that the dynamical critical exponent of the model is z = 0, with multiple hydrodynamic relaxation rates at criticality. We point out that the dynamical critical phenomena in N = 2* plasma is outside the dynamical universality classes established by Hohenberg and Halperin. [ABSTRACT FROM AUTHOR]

We extend Kodama-Ishibashi and Jansen-Rostworowski-Rutkowski master field framework to study quasinormal modes of black branes and black holes of Einstein gravity in D=5 space-time dimensions with multiple scalars and an arbitrary bulk potential. As an application, we consider a thermodynamically unstable state of mass deformed N=4 supersymmetric Yang-Mills theory at strong coupling. The corresponding gravitational dual is N=2* black brane with a dynamical instability of its translationary invariant horizon. We study the dependence of the quasinormal mode spectra as the boundary gauge theory is compactified on S3--the black brane is turned into the black hole. [ABSTRACT FROM AUTHOR]

We use holographic correspondence to study transport of the conformal plasma in R 2, 1 in a phase with a spontaneously broken global Z 2 symmetry. The dual black branes in a Poincare patch of asymptotically AdS 4 have "hair"--a condensate of the order parameter for the broken symmetry. This hair affects both the hydrodynamic and the nonhydrodynamic quasinormal modes of the black branes. Nonetheless, the shear viscosity of the conformal order is universal, the bulk viscosity vanishes and the speed of the sound waves is c 2 s = 1 2. We compute the low-lying spectrum of the nonhydrodynamic modes. We identify a quasinormal mode associated with the fluctuations of the Z 2 order parameter with the positive imaginary part. The presence of this mode in the spectrum renders the holographic conformal order perturbatively unstable. Correspondingly, the dual black branes violate the correlated stability conjecture. [ABSTRACT FROM AUTHOR]

Gauge theory/string theory holographic correspondence for N=4 supersymmetric Yang-Mills (SYM) theory is well under control in the planar limit, and for large (infinitely large)'t Hooft coupling, λ→∞. Certain aspects of the correspondence can be extended including O(λ-3/2) corrections. There are no reliable first principle computations of the N=4 plasma nonequilibrium properties beyond the stated order. We show extreme sensitivity of the nonhydrodynamic spectra of holographic N=4 SYM plasma to O(λ-3) corrections, challenging any conclusions reached from "resummation" of O(λ-3/2) corrections. [ABSTRACT FROM AUTHOR]

Microseconds after the Big Bang quarks and gluons formed a strongly coupled nonconformal liquid driven out of equilibrium by the expansion of the Universe. We use holography to determine the nonequilibrium behavior of this liquid in a Friedmann-Lemaître-Robertson-Walker universe and develop an expansion for the corresponding entropy production in terms of the derivatives of the cosmological scale factor. We show that the resulting series has zero radius of convergence and we discuss its resurgent properties. Finally, we compute the resummed entropy production rate in a de Sitter universe at late times and show that the leading order approximation given by bulk viscosity effects can strongly overestimate/underestimate the rate depending on the microscopic parameters. [ABSTRACT FROM AUTHOR]