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Related papers: Radiative Bulk Viscosity

200 papers

We present a discussion of the effects induced by bulk viscosity either on the very early Universe stability and on the dynamics associated to the extreme gravitational collapse of a gas cloud. In both cases the viscosity coefficient is…

General Relativity and Quantum Cosmology · Physics 2009-03-24 Nakia Carlevaro , Giovanni Montani

One of the most remarkable features of the Quark Gluon Plasma is its nearly perfect fluidity behavior indicated by the small shear viscosity to entropy density ratio obtained from fitting relativistic viscous hydrodynamics flow harmonics to…

Nuclear Theory · Physics 2015-12-22 Jacquelyn Noronha-Hostler

Considering viscous friction that varies spatially and temporally, the general expressions for entropy production, free energy, and entropy extraction rates are derived to a Brownian particle that walks in an overdamped and underdamped…

Statistical Mechanics · Physics 2021-04-28 Mesfin Asfaw Taye

The quarks are regarded as quasiparticles, which acquire an effective mass generated by the interaction with the other quarks of the dense system. The bulk viscosity is re-expressed in the case of interacting strange quark matter. We find…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zheng Xiaoping , Yang Shuhua , Li Jiarong

Bulk viscosity may serve to damp sound waves in a system of neutrinos coupled to very light scalar particles, in the era after normal neutrino decoupling but before recombination. We calculate the bulk viscosity parameter in a minimal…

Astrophysics · Physics 2009-11-11 R. F. Sawyer

We develop a nonlinear generalisation of the causal linear thermodynamics of bulk viscosity, incorporating positivity of the entropy production rate and the effective specific entropy. The theory is applied to viscous fluid inflation (which…

Astrophysics · Physics 2009-10-28 Roy Maartens , Vicenc Mendez

The ratio of shear viscosity to entropy density, $\eta/s$, is computed in various holographic geometries that break translation invariance (but are isotropic). The shear viscosity does not have a hydrodynamic interpretation in such…

High Energy Physics - Theory · Physics 2016-04-20 Sean A. Hartnoll , David M. Ramirez , Jorge E. Santos

We examine the cosmological consequences of an alternative to the standard expression for bulk viscosity, one which was proposed to avoid the propagation of superluminal signals without the necessity of extending the space of variables of…

General Relativity and Quantum Cosmology · Physics 2016-04-08 Marcelo M. Disconzi , Thomas W. Kephart , Robert J. Scherrer

Multiphase gas can be found in many astrophysical environments, such as galactic outflows, stellar wind bubbles, and the circumgalactic medium, where the interplay between turbulence, cooling, and viscosity can significantly influence gas…

Astrophysics of Galaxies · Physics 2026-05-15 Tirso Marin-Gilabert , Max Gronke , S. Peng Oh

We study an expanding two-fluid model of non-relativistic dark matter and radiation which are allowed to interact during a certain time span and to establish an approximate thermal equilibrium. Such interaction which generates an effective…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-08 Hermano Velten , Ingrid Costa , Winfried Zimdahl

The holographic principle in a radiation dominated universe is extended to incorporate the case of a bulk-viscous cosmic fluid. This corresponds to a nonconformally invariant theory. Generalization of the Cardy-Verlinde entropy formula to…

General Relativity and Quantum Cosmology · Physics 2009-01-14 Iver Brevik

We have obtained the Vlasov equation and Boltzmann kinetic equation using Poisson bracket (classical Hamilton equation) and Rindler Hamiltonian. Further, we treat the whole Universe as a statistical system with galaxies as the point…

General Physics · Physics 2017-01-17 Soma Mitra , Somenath Chakrabarty

We estimate dissipative properties viz: shear and bulk viscosities of hadronic matter using relativistic Boltzmann equation in relaxation time approximation within ambit of excluded volume hadron resonance gas (EHRG) model. We find that at…

High Energy Physics - Phenomenology · Physics 2015-09-14 Guru Prakash Kadam , Hiranmaya Mishra

Experiments at the Relativistic Heavy Ion Collider (RHIC) suggest that the state of matter produced in the experiments has a low shear-viscosity to entropy-density ratio. We ask here the question what is this ratio in usual finite nuclei at…

Nuclear Theory · Physics 2009-10-29 N. Auerbach , S. Shlomo

Radiative mixing layers arise wherever multiphase gas, shear, and radiative cooling are present. Simulations show that in steady state, thermal advection from the hot phase balances radiative cooling. However, many features are puzzling.…

Astrophysics of Galaxies · Physics 2021-07-12 Brent Tan , S. Peng Oh , Max Gronke

Fluid dynamics corresponds to the dynamics of a substance in the long wavelength limit. Writing down all terms in a gradient (long wavelength) expansion up to second order for a relativistic system at vanishing charge density, one obtains…

High Energy Physics - Theory · Physics 2010-01-22 Paul Romatschke

We study the dynamical response of viscous materials to gravitational waves, in the context of a fully relativistic theory of fluid dynamics. For the first time, we calculate oscillation modes and scattering properties of viscous stars.…

General Relativity and Quantum Cosmology · Physics 2024-11-27 Valentin Boyanov , Vitor Cardoso , Kostas D. Kokkotas , Jaime Redondo-Yuste

We interpret as shear viscosity the anisotropic pressure that emerges in inhomogeneous spherically symmetric spacetimes described by the Lemaitre-Tolman-Bondi (LTB) metric in a comoving frame. By assuming that local isotropic pressure and…

General Relativity and Quantum Cosmology · Physics 2008-12-24 Roberto A Sussman

The previous investigation on Rayleigh-B\'enard convection of a dilute classical gas [T. Kita: J. Phys. Soc. Jpn. {\bf 75} (2006) 124005] is extended to calculate entropy change of the convective transition with the rigid boundaries. We…

Statistical Mechanics · Physics 2009-11-13 Takafumi Kita

We estimate the temperature dependence of the bulk viscosity in a relativistic hadron gas. Employing the Green-Kubo formalism in the SMASH (Simulating Many Accelerated Strongly-interacting Hadrons) transport approach, we study different…

High Energy Physics - Phenomenology · Physics 2020-12-30 J. -B. Rose , J. M. Torres-Rincon , H. Elfner