Derek Teaney

How much do heavy quarks thermalize in a heavy ion collision

We investigate the thermalization of charm quarks in high-energy heavy-ion collisions. To this end, we calculate the diffusion coefficient in the perturbative quark gluon plasma and relate it to collisional energy loss and momentum broadening. We then use these transport properties to formulate a Langevin model for the evolution of the heavy quark spectrum in the hot medium. The model is strictly valid in the nonrelativistic limit and for all velocities

Nearly perfect fluidity: from cold atomic gases to hot quark gluon plasmas

\ensuremath{\gamma}vl\ensuremath{\alpha}{s}^{\ensuremath{-}1/2}

Heavy ions and string theory

to leading logarithm in

Viscous Hydrodynamics and the Quark Gluon Plasma

T/{m}_{D}

Thermal Noise and Stochastic Strings in AdS/CFT

. The corresponding Fokker-Planck equation can be solved analytically for a Bjorken expansion and the solution gives a simple estimate for the medium modifications of the heavy quark spectrum as a function of the diffusion coefficient. Finally we solve the Langevin equations numerically in a hydrodynamic simulation of the heavy-ion reaction. The results of this simulation are the medium modifications of the charm spectrum

Non linearities in the harmonic spectrum of heavy ion collisions with ideal and viscous hydrodynamics

{R}_{\mathit{AA}}

Heavy quark diffusion from the lattice

and the expected elliptic flow

Next-to-leading order thermal photon production in a weakly coupled quark-gluon plasma

{v}_{2}({p}_{T})

Spectral densities for hot QCD plasmas in a leading-log approximation

as a function of the diffusion coefficient.

Fluctuation, dissipation, and thermalization in nonequilibrium AdS(5) black hole geometries

Shear viscosity is a measure of the amount of dissipation in a simple fluid. In kinetic theory shear viscosity is related to the rate of momentum transport by quasi-particles, and the uncertainty relation suggests that the ratio of shear viscosity ? to entropy density s in units of /kB is bounded by a constant. Here, is Plancks constant and kB is Boltzmanns constant. A specific bound has been proposed on the basis of string theory where, for a large class of theories, one can show that ?/s ? /(4?kB). We will refer to a fluid that saturates the string theory bound as a perfect fluid. In this review we summarize theoretical and experimental information on the properties of the three main classes of quantum fluids that are known to have values of ?/s that are smaller than /kB. These fluids are strongly coupled Bose fluids, in particular liquid helium, strongly correlated ultracold Fermi gases and the quark gluon plasma. We discuss the main theoretical approaches to transport properties of these fluids: kinetic theory, numerical simulations based on linear response theory and holographic dualities. We also summarize the experimental situation, in particular with regard to the observation of hydrodynamic behavior in ultracold Fermi gases and the quark gluon plasma.