Related papers: Bulk viscosity in strong and electroweak matter
The article communicates an alternative route to suffice the late-time acceleration considering a bulk viscous fluid with viscosity coefficient $\zeta =\zeta _{0}+ \zeta _{1} H + \zeta _{2} H^{2}$, where $\zeta _{0}, \zeta _{1}, \zeta _{2}$…
We have gone through a comparative study on two different kind of bulk viscosity expressions by using a common dynamical model. The Polyakov-Nambu-Jona-Lasinio (PNJL) model in the realm of mean-field approximation, including up to eight…
A new method is proposed to compute the bulk viscosity in strange quark matter at high densities. Using the method it is straightforward to prove that the bulk viscosity is positive definite, which is not so easy to accomplish in other…
The bulk viscosity determines dissipation during hydrodynamic expansion. It vanishes in scale invariant fluids, while a nonzero value quantifies the deviation from scale invariance. For the dilute Fermi gas the bulk viscosity is given…
State-of-the-art fluid dynamical simulations of relativistic heavy-ion collisions employ initial state models which result in a rather strong radial flow. In order to fit the experimental observables, a non-negligible bulk viscosity of the…
A general formalism for calculating the bulk viscosity of strange quark matter is developed. Contrary to the common belief that the non-leptonic processes alone give the dominant contribution to the bulk viscosity, the inclusion of the Urca…
In this paper, bulk viscosity is introduced in new holographic dark energy (HDE) to describe the effects of cosmic non-perfect fluid on the evolution of the universe in modified $f(R,T)$ gravity. Assuming $f(R,T)=R+\lambda T$, where $R$ is…
This article explores the impact of bulk viscosity on understanding the universe's accelerated expansion within the context of modified $f(T,\mathcal{T})$ gravity, which is an extension of the $f(T)$ gravitational theory, allowing a broad…
In this work, we have studied how incorporating viscous fluids leads to exact bounce cosmological solutions in general relativity (GR) framework. Specifically, we propose a novel parameterization of bulk viscosity coefficient of the form…
We investigate the influence of bulk viscosity on late-time cosmic acceleration within an extended $f(Q, L_m)$ gravity framework, where the non-metricity $Q$ is non-minimally coupled with the matter Lagrangian $L_m$. Analyzing the function…
Hydro-kinetic theory of thermal fluctuations is applied to a non-conformal relativistic fluid. Solving the hydro-kinetic equations for an isotropically expanding background we find that hydrodynamic fluctuations give ultraviolet divergent…
We study the bulk viscosity of moderately hot and dense, neutrino-transparent relativistic $npe\mu$ matter arising from weak-interaction direct Urca processes. This work parallels our recent study of the bulk viscosity of $npe\mu$ matter…
We study the bulk viscosity of dense matter, taking into account non-linear effects which arise in the large amplitude "supra-thermal" region where the deviation $\mu_\Delta$ of the chemical potentials from chemical equilibrium fulfills…
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…
This work investigates the bulk viscosity of warm, dense, neutrino-transparent, color-superconducting quark matter, where damping of density oscillations in the kHz frequency range arises from weak-interaction-driven direct Urca processes…
We present results on bulk thermodynamic quantities as well as net baryon number, strangeness and electric charge fluctuations in QCD at non-zero density and temperature obtained from lattice calculations with almost physical quark masses…
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…
Intrinsic bulk viscosity of the one-component plasma (OCP) is computed and analyzed using equilibrium molecular dynamics simulations and the Green-Kubo formalism. It is found that bulk viscosity exhibits a maximum at $\Gamma \approx 1$,…
The bulk viscosity of thermalized QCD matter at temperatures above a few hundred MeV could be significantly influenced by charm quarks because their contribution arises four perturbative orders before purely gluonic effects. In an attempt…
We compute the bulk viscosity of a gas of pions at temperatures below the QCD crossover temperature, for the physical value of pion mass, to lowest order in chiral perturbation theory. Bulk viscosity is controlled by number-changing…