Observations are providing increasingly detailed quantitative information about the accretion flows that power such high energy systems as X-ray binaries and active galactic nuclei. Analytic models of such systems must rely on assumptions such as regular flow geometry and a simple, parameterized stress. Global numerical simulations offer a way to investigate the basic physical dynamics of accre...

We shortly discuss several astrophysical scenarios leading to cosmic ray acceleration up to extremely high energies reaching the scale of 10 eV. The processes suggested in the literature include acceleration at relativistic jet terminal shocks and shear boundary layers, shocks in large scale accretion flows onto supergalactic cosmic structures, particle reflections from ultra-relativistic shock...

We study entanglement entropies of simply connected surfaces in field theories dual to Lovelock gravities. We consider Gauss-Bonnet and cubic Lovelock gravities in detail. In the conformal case the logarithmic terms in the entanglement entropy are governed by the conformal anomalies of the CFT; we verify that the holographic calculations are consistent with this property. We also compute the ho...

High resolution, non-oscillatory, central difference (NOCD) numerical schemes are introduced as alternatives to more traditional artificial viscosity (AV) and Godunov methods for solving the fully general relativistic hydrodynamics equations. These new approaches provide the advantages of Godunov methods in capturing ultra-relativistic flows without the cost and complication of Riemann solvers,...

Feedback provided by relativistic jets may be effective in shaping the galaxy luminosity function. The quenching mode (quasar mode) at redshifts ∼2-3 potentially disperses gas in star-forming galaxies. The maintenance mode (radio mode) heats the gas in galaxy clusters counteracting cooling flows. A number of authors have examined the effect of relativistic jets in dispersing clouds in the kpc-s...

Many astrophysical phenomena exhibit relativistic radiative flows. While velocities in excess of v ∼ 0.1c can occur in these systems, it has been common practice to approximate radiative transfer to O(v/c). In the case of neutrino transport in core-collapse supernovae, this approximation gives rise to an inconsistency between the lepton number transfer and lab frame energy transfer, which have ...

We investigate the structure and dynamics of the M87 jet based on multi-frequency VLBI observations and MHD jet theories. Millimeter VLBI cores are considered as innermost jet emissions. The jet structure up to ∼ 105 rs is described as a parabolic streamline, indicating the lateral expansion under a confinement by the stratified ISM. Thus, the jet collimation maintains in five orders of magnitu...

A special version of multi–dimensional simple waves given in [G. Boillat, J. Math. Phys. 11, 1482-3 (1970)] and [G.M. Webb, R. Ratkiewicz, M. Brio and G.P. Zank, J. Plasma Phys. 59, 417-460 (1998)] is employed for fully relativistic fluid and plasma flows. Three essential modes: vortex, entropy and sound modes are derived where each of them is different from its nonrelativistic analogue. Vortex...

in this paper, at first we have formulated the lowest order constrained variational method for the relativistic case of an interacting fermion system at finite temperature. then we have used this formalism to calculate some thermodynamic properties of liquid in the relativistic regime. the results show that the difference between total energies of relativistic and non-relativistic cases of liqu...