Microscopic black holes explode with their temperature varying inversely as their mass. Such explosions would lead to the highest temperatures in the present universe, all the way to the Planck energy. Whether or not a quasi-stationary shell of matter undergoing radial hydrodynamic expansion surrounds such black holes has been controversial. In this paper relativistic viscous fluid equations ar...

A bstract We derive the first and second-order expressions for shear, bulk viscosity, thermal conductivity of a relativistic hot boson gas in magnetic field using kinetic theory within Chapman-Enskog method. The order-by-order off-equilibrium distribution function is obtained terms associate Laguerre polynomial with field-dependent coefficients Boltzmann-Uehling-Uhlenbeck transport equation. an...

We compute shear viscosity and flavor diffusion coefficients for ultra-relativistic gauge theory with many fermionic species, Nf≫1, to leading order in 1/Nf . The calculation is performed both at leading order in the effective coupling strength gNf , using the Hard Thermal Loop (HTL) approximation, and completely to all orders in gNf . This constitutes a nontrivial test of how well the HTL appr...

We present fully general relativistic equations governing viscous transonic flows in vertical equilibrium in Kerr geometry. We find the complete set of global solutions (both for Optically thick and optically thin flows) in the weak viscosity limit. We show that for a large region of parameter space, centrifugal pressure supported standing shocks can form in accretion and winds very close to th...

After reviewing some basic concepts of the theory of strongly interacting matter at above nuclear energy density and reviewing some salient results of the experimental program at the Relativistic Heavy Ion Collider (RHIC), these lectures explain why the quark-gluon plasma observed in the RHIC experiments has been called a “perfect liquid.” They then give an introduction to some recent ideas con...

The first-order general relativistic theory of a generic dissipative (heatconducting, viscous, particle-creating) fluid is rediscussed from a unified covariant frame-independent point of view. By generalizing some previous works in the literature, we derive a formula for the temperature variation rate, which is valid both in Eckart’s (particle) and in the Landau-Lifshitz (energy) frames. Partic...

Direct photon emission in heavy-ion collisions is calculated within the relativistic microscopic transport model UrQMD. We compare the results from the pure transport calculation to a hybrid-model calculation, where the high-density part of the evolution is replaced by an ideal 3-dimensional fluiddynamic calculation. The effects of viscosity, present in the transport model but neglected in idea...

We estimate the Shakura-Sunyaev viscosity parameter alpha for diierent values of the shear/vorticity ratio, =!, using local simulations of dynamo-generated turbulence. We nd that the time average of is approximately proportional to =! (at least for =! < 10). We point out that this result may have important implications for the properties of thick accretion discs, because there ! is small and wo...

We summarize recent results regarding the equilibrium and non-equilibrium behavior of cold dilute atomic gases in the limit in which the two body scattering length a goes to infinity. In this limit the system is described by a Galilean invariant (non-relativistic) conformal field theory. We discuss the low energy effective lagrangian appropriate to the limit a → ∞, and compute low energy coeffi...