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Related papers: Cosmological Implications of QGP Bulk Viscosity

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The Generalized Uncertainty Principle (GUP), which has been predicted by various theories of quantum gravity near the Planck scale is implemented on deriving the thermodynamics of ideal Quark-Gluon Plasma (QGP) consisting of two massless…

High Energy Physics - Phenomenology · Physics 2014-10-24 I. Elmashad , A. Farag Ali , L. I. Abou-Salem , Jameel-Un Nabi , A. Tawfik

The bulk and shear viscosities ($\eta$ and $\zeta$) have been studied for quark-gluon-plasma produced in relativistic heavy ion collisions within semi-classical transport theory, in a recently proposed quasi-particle model of (2+1)-flavor…

Nuclear Theory · Physics 2012-12-06 Vinod Chandra

We discuss two important modifications of inflationary paradigm. Until very recently we believed that inflation automatically leads to flatness of the universe, Omega = 1. We also thought that post-inflationary phase transitions in GUTs may…

Astrophysics · Physics 2007-05-23 Andrei Linde

We discuss a new scenario for early cosmology, when inflationary de Sitter phase dynamically emergent. This genuine quantum effect occurs as a result of dynamics of the topologically nontrivial sectors in a (conjectured) strongly coupled…

High Energy Physics - Phenomenology · Physics 2014-08-13 Ariel R. Zhitnitsky

The sequence of phase transitions during the hot history of the universe is followed within a phenomenological framework. Particular emphasis is put on the QCD confinement transition, which is at reach under earth laboratory conditions. A…

Astrophysics · Physics 2017-09-27 B. Kampfer

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 explain how a $SU(N_c)$ gauge theory, decoupled from the standard model and with a high-lying strong coupling scale, can incorporate apparently unrelated cosmological features, such as Inflation and dark matter, using well-understood…

High Energy Physics - Phenomenology · Physics 2018-05-08 Melissa Mendes , Giorgio Torrieri

Based on the kinetic theory with relaxation time approximation, we investigate the bulk viscosity ($\zeta$) and its ratio to shear viscosity ($\zeta/\eta$) of quark matter at finite temperature and chemical potential with the in-medium…

High Energy Physics - Phenomenology · Physics 2026-01-16 Chong-long Xie , Guo-yun Shao , Ming-zheng-xuan Wu , Wei-bo He

We study the effects of a finite chemical potential on the occurrence of cavitation in a quark gluon plasma (QGP). We solve the evolution equations of second order viscous relativistic hydrodynamics using three different equations of state.…

High Energy Physics - Phenomenology · Physics 2015-08-17 S. M. Sanches , D. A. Fogaça , F. S. Navarra , H. Marrochio

Experimental studies of the Quark-Gluon Plasma (QGP) focus on two, in practice distinct, regimes: one in which the baryonic chemical potential $\mu_B$ is essentially zero, the other in which it is of the same order of magnitude as the…

High Energy Physics - Theory · Physics 2016-03-02 Brett McInnes

Kubo's formula relates bulk viscosity to the retarded Green's function of the trace of the energy-momentum tensor. Using low energy theorems of QCD for the latter we derive the formula which relates the bulk viscosity to the energy density…

High Energy Physics - Phenomenology · Physics 2008-11-26 D. Kharzeev , K. Tuchin

The effect of bulk viscisity on the evolution of the homogeneous and isotropic cosmological models is considered. Solutions are found, with a barotropic equation of state, and a viscosity coefficient that is proportional to a power of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pimentel L O , Diaz-Rivera L M

The collective behavior of hadrons and of electromagnetic radiation in heavy-ion collisions has been widely used to study the properties of the the Quark-Gluon Plasma (QGP). Indeed this collectivity, as measured by anisotropic flow…

For temperatures $T$ ranging from a few MeV up to TeV and energy density $\rho$ up to $10^{16}~$GeV/fm$^3$, the bulk viscosity $\zeta$ is calculated in non-perturbation (up, down, strange, charm, and bottom) and perturbation theories with…

High Energy Physics - Phenomenology · Physics 2021-10-06 Abdel Nasser Tawfik , Carsten Greiner

We consider a novel model of cosmic inflation. In our model one does not need any specific matter field to drive inflation, but inflation stems from the microscopic, Planck scale structure of spacetime, thus being of quantum gravitational…

General Relativity and Quantum Cosmology · Physics 2014-08-28 Jarmo Mäkelä

Warm inflation model with bulk viscous pressure in the context of "intermediate inflation" where the cosmological scale factor expands as $a(t)=a_0\exp(At^f)$, is studied. The characteristics of this model in slow-roll approximation and in…

General Relativity and Quantum Cosmology · Physics 2015-06-18 M. R. Setare , V. Kamali

Exact solutions for a model with variable $G$, $\Lambda$ and bulk viscosity are obtained. Inflationary solutions with constant (de Sitter-type) and variable energy density are found. An expanding anisotropic universe is found to isotropize…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Arbab I. Arbab

Currently there is intense interest in the properties of the Quark-Gluon Plasma produced in peripheral collisions of heavy ions at various facilities, such as the RHIC. In particular, it is essential to understand the difference between…

High Energy Physics - Theory · Physics 2018-08-03 Brett McInnes

Based on the first principle calculation, a Lagrangian for the system describing quarks, gluons, and their interactions, is constructed. Ascribed to the existence of dissipative behavior as a consequence of strong interaction within…

High Energy Physics - Phenomenology · Physics 2015-05-20 T. P. Djun , B. Soegijono , T. Mart , L. T. Handoko

In this study, we explore the accelerated expansion of the universe within the framework of modified $f(Q)$ gravity. The investigation focus on the role of bulk viscosity in understanding the universe's accelerated expansion. Specifically,…

General Relativity and Quantum Cosmology · Physics 2024-07-09 Dheeraj Singh Rana , P. K. Sahoo