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Related papers: Bulk viscosity in quasi particle models

200 papers

In this study, we analyze the transport properties of the Quark-Gluon Plasma, focusing on bulk ($\zeta$) and shear ($\eta$) viscosities at vanishing chemical potential. To describe the QGP, we employ a quasiparticle model for quarks along…

High Energy Physics - Phenomenology · Physics 2025-01-03 Sadaf Madni , Arghya Mukherjee , Amaresh Jaiswal , Najmul Haque

We study the ratio of bulk to shear viscosity in gluodynamics within a phenomenological quasiparticle model. We show that at large temperatures this ratio exhibits a quadratic dependence on the conformality measure as known from weak…

High Energy Physics - Phenomenology · Physics 2015-05-30 M. Bluhm , B. Kampfer , K. Redlich

We study the behavior of the bulk viscosity $\zeta$ in QCD near a possible critical endpoint in the phase diagram. We verify the expectation that $(\zeta/s)\sim a(\xi/\xi_0)^{x_\zeta}$, where $s$ is the entropy density, $\xi$ is the…

High Energy Physics - Phenomenology · Physics 2019-10-23 Mauricio Martinez , Thomas Schaefer , Vladimir Skokov

We present simulations of stochastic fluid dynamics in the vicinity of a critical endpoint belonging to the universality class of the Ising model. This study is motivated by the challenge of modeling the dynamics of critical fluctuations…

Nuclear Theory · Physics 2024-07-23 Chandrodoy Chattopadhyay , Josh Ott , Thomas Schaefer , Vladimir V. Skokov

We investigate the first-order transport coefficients of a fluid made of quasiparticles with a temperature-dependent mass extracted from chiral models. We describe this system using an effective kinetic theory, given by the relativistic…

High Energy Physics - Phenomenology · Physics 2026-03-17 Pedro Nogarolli , Gabriel S. Denicol , Eduardo S. Fraga

The evaluation of hydrodynamic transport coefficients in relativistic field theory, and the emergence of an effective kinetic theory description, is examined. Even in a weakly-coupled scalar field theory, interesting subtleties arise at…

High Energy Physics - Phenomenology · Physics 2009-10-28 Sangyong Jeon , Laurence G. Yaffe

We derive an analytical connection between kinetic relaxation rate and bulk viscosity of a relativistic fluid in d spatial dimensions, all the way from the ultra-relativistic down to the near non-relativistic regime. Our derivation is based…

Fluid Dynamics · Physics 2020-06-23 A. Gabbana , D. Simeoni , S. Succi , R. Tripiccione

We study the bulk and shear viscosity and the electrical conductivity in a quasiparticle approach to Yang-Mills theory and QCD with light and strange quarks to assess the dynamical role of quarks in transport properties at finite…

High Energy Physics - Phenomenology · Physics 2021-01-13 Valeriya Mykhaylova , Chihiro Sasaki

Second-order phase transitions are characterized by a divergence of the spatial correlation length of the order parameter fluctuations. For confined systems, this is known to lead to remarkable equilibrium physical phenomena, including…

Statistical Mechanics · Physics 2017-05-15 Christian M. Rohwer , Andrea Gambassi , Matthias Krüger

A phenomenological quasiparticle model, featuring dynamically generated self-energies of excitation modes, successfully describes lattice QCD results relevant for the QCD equation of state and related quantities both at zero and non-zero…

High Energy Physics - Phenomenology · Physics 2009-11-18 M. Bluhm , B. Kampfer , K. Redlich

In this paper the nonequilibrium correction to the distribution function containing a time and space dependent mass is obtained. Given that, fully consistent fluid dynamic equations are formulated. Then, the physics of the bulk viscosity is…

Nuclear Theory · Physics 2020-04-28 Alina Czajka , Sigtryggur Hauksson , Chun Shen , Sangyong Jeon , Charles Gale

We present the derivation of second-order relativistic viscous hydrodynamics from an effective Boltzmann equation for a system consisting of quasiparticles of a single species. We consider temperature-dependent masses of the quasiparticles…

Nuclear Theory · Physics 2017-03-15 Leonardo Tinti , Amaresh Jaiswal , Radoslaw Ryblewski

In this paper, we introduce bulk viscosity in the formalism of modified gravity theory in which the gravitational action contains a general function $f(R,T)$, where $R$ and $T$ denote the curvature scalar and the trace of the…

General Relativity and Quantum Cosmology · Physics 2015-03-02 C. P. Singh , Pankaj Kumar

We use Monte Carlo and molecular dynamics simulations to study phase behavior and transport properties in a symmetric binary fluid where particles interact via Lennard-Jones potential. Our results for the critical behavior of collective…

Statistical Mechanics · Physics 2018-03-09 Sutapa Roy , Subir K. Das

The ratio of bulk to shear viscosity is expected to exhibit a different behaviour in weakly and in strongly coupled systems. This can be expressed by its dependence on the squared sound velocity. In the high temperature QCD plasma at small…

High Energy Physics - Phenomenology · Physics 2015-05-27 M. Bluhm , B. Kampfer , K. Redlich

In the hadronic phase, the dominant configuration of QCD with two flavors of massless quarks is a gas of massless pions. We calculate the bulk viscosity (zeta) using the Boltzmann equation with the kinetic theory generalized to incorporate…

High Energy Physics - Phenomenology · Physics 2014-05-19 Jiunn-Wei Chen , Juven Wang

This work explores the influence of viscous fluids on cosmological dynamics within the framework of General Relativity. We introduce a novel time-dependent parametrization for the bulk viscosity coefficient, given by \(\zeta = \zeta_0 (t -…

General Relativity and Quantum Cosmology · Physics 2025-04-30 Rajdeep Mazumdar , Mrinnoy M. Gohain , Kalyan Bhuyan

We study the bulk viscosity of a pion gas in unitarized Chiral Perturbation Theory at low and moderate temperatures, below any phase transition to a quark-gluon plasma phase. We argue that inelastic processes are irrelevant and…

High Energy Physics - Phenomenology · Physics 2015-05-27 Antonio Dobado , Felipe J. Llanes-Estrada , Juan M. Torres-Rincon

We study the shear and bulk viscosities of partonic and hadronic matter as functions of temperature T within the parton-hadron-string dynamics (PHSD) off-shell transport approach. Dynamical hadronic and partonic systems in equilibrium are…

High Energy Physics - Phenomenology · Physics 2015-06-12 V. Ozvenchuk , O. Linnyk , M. I. Gorenstein , E. L. Bratkovskaya , W. Cassing

Assuming that the Hagedorn fluid composed of known particles and resonances with masses $m<2\,$GeV obeys the {\it first-order} theory (Eckart) of relativistic fluid, we discuss the transport properties of QCD confined phase. Based on the…

High Energy Physics - Phenomenology · Physics 2010-11-24 A. Tawfik , M. Wahba