A new Parametrization for Bulk Viscosity Cosmology as Extension of the $\Lambda$CDM Model

Abstract

Bulk viscosity in cold dark matter is an appealing feature that introduces distinctive phenomenological effects in the cosmological setting as compared to the $\Lambda$CDM model. Under this view, we propose a general parametrization of the bulk viscosity of the form $\xi \sim H^{1-2s}{\rho }_m^s$, that covers intriguingly some well-known cases in the Eckart's theory. Some advantages of this novel parametrization are: first, it allows to write the resulting equations of cosmological evolution in the form of an autonomous system for any value of $s$, so a general treatment of the fixed points and stability can be done, and second, the bulk viscosity effect is consistently handled so that it naturally turns off when matter density vanishes. As a main result we find, based on detailed dynamical system analysis, one-parameter family of de-Sitter-like asymptotic solutions with non-vanishing bulk viscosity coefficient during different cosmological periods. Numerical computations are performed jointly along with analytical phase space analysis in order to assess more quantitatively the bulk viscosity effect on the cosmological background evolution. Finally, as a first contact with observation we derive constraints on the free parameters of some bulk viscosity models with specific $s$-exponents from Supernovae Ia and observations of the Hubble parameter, by performing a Bayesian statistical analysis thought the Markov Chain Monte Carlo method.

arXiv comment26 pages, 6 figures. Typos fixed, phase space diagrams included (figure 1). Accepted for publication in the European Physical Journal Plus

References in corpus (63)

• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• emcee: The MCMC Hammer
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample
• The Complete Light-curve Sample of Spectroscopically Confirmed Type Ia Supernovae from Pan-STARRS1 and Cosmological Constraints from The Combined Pantheon Sample
• Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics Beyond LambdaCDM
• An absorption profile centred at 78 megahertz in the sky-averaged spectrum
• A 6% measurement of the Hubble parameter at $z\sim 0.45$: direct evidence of the epoch of cosmic re-acceleration
• Inhomogeneous Equation of State of the Universe: Phantom Era, Future Singularity and Crossing the Phantom Barrier
• Cosmic anti-friction and accelerated expansion
• Dissipative hidden sector dark matter
• Damping scales of neutralino cold dark matter
• Dark Energy and Viscous Cosmology
• Correcting Type Ia Supernova Distances for Selection Biases and Contamination in Photometrically Identified Samples
• Does Bulk Viscosity Create a Viable Unified Dark Matter Model?
• Cosmological model with viscosity media (dark fluid) described by an effective equation of state
• Bulk viscosity driving the acceleration of the Universe
• The Cardassian expansion revisited: constraints from updated Hubble parameter measurements and Type Ia Supernovae data
• Exploring Cosmological Expansion Parametrizations with the Gold SnIa Dataset
• Structure Formation with Mirror Dark Matter: CMB and LSS
• Solving the small-scale structure puzzles with dissipative dark matter
• Dark goo: Bulk viscosity as an alternative to dark energy
• Viscous dark fluid universe
• Using Pantheon and DES supernova, baryon acoustic oscillation, and Hubble parameter data to constrain the Hubble constant, dark energy dynamics, and spatial curvature
• Can a matter-dominated model with constant bulk viscosity drive the accelerated expansion of the universe?
• Exploring a matter-dominated model with bulk viscosity to drive the accelerated expansion of the Universe
• Bulk Viscosity, Decaying Dark Matter, and the Cosmic Acceleration
• Friedmann cosmology with bulk viscosity: a concrete model for dark energy
• "Understanding" cosmological bulk viscosity
• Constraints on dissipative unified dark matter
• Inflation in a viscous fluid model
• Is there concordance within the concordance $\Lambda$CDM model?
• Qualitative Viscous Cosmology
• Bulk viscous matter and recent acceleration of the Universe
• Qualitative Analysis of Viscous Fluid Cosmological Models satisfying the Israel-Stewart theory of Irreversible Thermodynamics
• Cosmic viscosity as a remedy for tension between PLANCK and LSS data
• Large scale structure from viscous dark matter
• Constraints on dark-matter properties from large-scale structure
• Accelerated and decelerated expansion in a causal dissipative cosmology
• An analysis of the $H_0$ tension problem in a universe with a viscous dark fluid
• Characteristic Properties of Two Different Viscous Cosmology Models for the Future Universe
• General Bulk-Viscous Solutions and Estimates of Bulk Viscosity in the Cosmic Fluid
• Late Decaying Dark Matter, Bulk Viscosity and the Cosmic Acceleration
• Structure formation in a $\Lambda$ $viscous$ CDM universe
• Dark sector interactions and the curvature of the Universe in light of Planck's 2018 data
• Viscous dark matter and 21 cm cosmology
• Constraints and cosmography of $\Lambda$CDM in presence of viscosity
• Analysing dissipative effects in the $\Lambda$CDM model
• Phase space analysis of bulk viscous matter dominated universe
• Viscous Self Interacting Dark Matter and Cosmic Acceleration
• Assessing the impact of bulk and shear viscosities on large scale structure formation
• Causal Bulk Viscous Dissipative Isotropic Cosmologies with Variable Gravitational and Cosmological Constants
• Renormalization-group flow of the effective action of cosmological large-scale structures
• Stability analysis and constraints on interacting viscous cosmology
• Cosmological test on viscous bulk models using Hubble Parameter measurements and type Ia Supernovae data
• Viscosity in cosmic fluids
• A hybrid model of viscous and Chaplygin gas to tackle the Universe acceleration
• Can the Hubble tension be resolved by bulk viscosity?
• Dynamics of viscous cosmologies in the full Israel-Stewart formalism
• A Non-minimally Coupled Potential for Inflation and Dark Energy after Planck 2015: A Comprehensive Study
• Observational constraints on unified dark matter including Hubble parameter data
• Study of a viscous $\Lambda$WDM model: Near equilibrium condition, entropy production, and cosmological constraints
• Inclusive Constraints on Unified Dark Matter Models from Future Large-Scale Surveys

Cited by in corpus (7)

• Dynamical Vacuum Compressibility of Space
• WIMP dark matter in bulk viscous non-standard cosmologies
• Cosmic Evolution of the Kantowski-Sachs Universe in the Context of a Bulk Viscous String in Teleparallel Gravity
• Cosmological constraints in symmetric teleparallel gravity with bulk viscosity
• FIMP Dark Matter in bulk viscous non-standard cosmologies
• Testing a nonlinear solution of the Israel-Stewart theory
• Role of viscous fluid in FLRW model with observational constraints