Dynamics of stationary axisymmetric configuration of the viscous accreting fluids surrounding a non-rotating compact object in final stages of accretion flow is presented here. For the special case of thin disk approximation, the relativistic fluid equations ignoring self-gravity of the disk are derived in Schwarzschild geometry. For two different state equations, two sets of self-consistent an...

In this paper, we calculate the relativistic bulk tensor and shear tensor of the relativistic accretion ows in the Kerr metric, overall and without any approximation. We obtain the relations of all components of the relativistic bulk and shear tensor in terms of components of four-velocity and its derivatives, Christoffel symbols and metric components in the BLF. Then, these components are deri...

We obtain criteria for shock wave (SW) existence in relativistic magnetic hydrodynamics with with no suppositions about convex-ity of the equation of state. Method of derivation involves consideration of a continuous SW profile in presence of Landau-Lifshitz relativistic viscosity tensor with both non-zero viscosity coefficients η and ζ. We point out that supposition of viscous profile existenc...

A new code and methodology are introduced for solving the general relativistic magnetohydrodynamic (GRMHD) equations in fixed background spacetimes using time-explicit, finitevolume discretization. The code has options for solving the GRMHD equations using traditional artificial-viscosity (AV) or non-oscillatory central difference (NOCD) methods, or a new extended AV (eAV) scheme using artifici...

We report recent progress on causal viscous hydrodynamics for relativistic heavy ion collisions. For fixed specific shear viscosity η/s, uncertainties in the elliptic flow arising from initial conditions, equation of state, bulk viscosity and numerical viscosity, and the treatment of the highly viscous hadronic stage and freeze-out procedure are analysed. A comparison of current viscous hydrody...

Head on collision of localized waves in cold and dense hadronic matter with and without shear and bulk viscosities is investigated. Non-relativistic dynamics of propagating waves is studied using the hydrodynamics description of the system and suitable equation of state. It will be shown that the localized waves are described by solutions of the Burgers equation. Simulations show that the propa...

We derive and analyze a simplified formulation of the numerical viscosity terms appearing in the expression of the numerical fluxes associated to several High-Resolution Shock-Capturing schemes. After some algebraic preprocessing, we give explicit expressions for the numerical viscosity terms of two of the most widely used flux formulae, which implementation saves computational time in multidim...

We present recent results on the calculation of transport coefficients for a pion gas at zero chemical potential in Chiral Perturbation Theory using Linear Response Theory. More precisely, we show the behavior of DC conductivity and shear viscosity at low temperatures. To compute transport coefficients, the standard power counting of ChPT has to be modified. The effects derived from imposing un...