Energy loss of a heavy quark moving through N=4 supersymmetric Yang-Mills plasma

We consider heavy-quark energy loss and pT-broadening in a strongly-coupled N=4 Super Yang Mills (SYM) plasma, and the problem of finite-extend matter is addressed. When expressed in terms of the appropriate saturation momentum, one finds identical parametric forms for the energy loss in pQCD and SYM theory, while pT-broadening is radiation dominated in SYM theory and multiple scattering dominated in pQCD.

We compute finite 't Hooft coupling corrections to observables related to charged quantities in a strongly coupled $\mathcal{N}=4$ supersymmetric Yang-Mills plasma. The coupling corrected equations of motion of gauge fields are explicitly derived and differ from findings of previous works, which contained several small errors with large impact. As a consequence the $\mathcal{O}(\gamma)$-corrections to the observables considered, including the conductivity, quasinormal mode fr...

We use the gauge-string duality to study heavy quarks in the presence of higher derivative corrections. These corrections correspond to the finite coupling corrections on the properties of heavy quarks in a hot plasma. In particular, we study the effects of these corrections on the energy loss and the dissociation length of a quark-antiquark pair. We show that the calculated energy loss of heavy quarks through the plasma increases. We also find in general that the dissociatio...

We compute the non-equilibrium stress tensor induced by a heavy quark moving through weakly coupled QCD plasma at the speed of light and compare the result to N = 4 Super Yang Mills theory at strong coupling. The QCD Boltzmann equation is reformulated as a Fokker-Planck equation in a leading log approximation which is used to compute the induced stress. The transition from nonequilibrium at short distances to equilibrium at large distances is analyzed with first and second or...

We study several observables related to heavy quarks in strongly coupled plasmas using the gauge/gravity correspondence. Besides the AdS_5 space dual to N=4 supersymmetric Yang-Mills theory we consider large classes of theories obtained from various deformations of the AdS_5 space. Among them are theories that solve equations of motion of a 5-dimensional Einstein-Hilbert-scalar action. Specifically, we calculate the screening distance of a heavy quark-antiquark pair moving at...

A number of recent papers have applied the AdS/CFT correspondence to a strong-coupling calculation of the medium-induced radiative parton energy loss in nucleus-nucleus collisions at RHIC. The predicted value of the "jet quenching parameter" q, however, is rather small compared to the experimental results. For hot N=4 supersymmetric Yang-Mills theory, certain marginal deformations can have the effect of enhancing q. This result is highly sensitive to the location of the funda...

We discuss the application of the AdS/CFT correspondence to possibly gain new physical insights for the strongly coupled quark-gluon plasma. This article provides an informal summary of a talk given by RCM at the 18th International Conference on General Relativity and Gravitation in July 2007.

We use perturbation theory to compute the diffusion coefficient of a heavy quark or scalar moving in N=4 SU(N_c) Super Yang-Mills plasma to leading order in the coupling and the ratio T/M<<1. The result is compared both to recent strong coupling calculations in the same theory and to the corresponding weak coupling result in QCD. Finally, we present a compact and simple formulation of the Lagrangian of our theory, N=4 SYM coupled to a massive fundamental N=2 hypermultiplet, w...

By using the AdS/CFT correspondence we study the deep inelastic scattering of an R-current off a N=4 supersymmetric Yang-Mills (SYM) plasma at finite temperature and strong coupling. Within the supergravity approximation valid when the number of colors is large, we compute the structure functions by solving Maxwell equations in the space-time geometry of the AdS_5 black three-brane. We find a rather sharp transition between a low energy regime where the scattering is weak and...

We estimate the stopping length of an energetic gluon in a thermal plasma of strongly coupled N=4 super-Yang-Mills theory by representing the gluon as a doubled string rising up out of the horizon.