A non-singular early-time viscous cosmological model
arXiv:2207.14244 · doi:10.1142/S0217732323500888
Abstract
In this paper, we study the thermodynamical and mathematical consistencies for a non-singular early-time viscous cosmological model known as soft-Big Bang, which was previously found in [N. Cruz, E. González, and J. Jovel, Phys. Rev. D \textbf{105}, 024047 (2022)]. This model represents a flat homogeneous and isotropic universe filled with a dissipative radiation fluid and a cosmological constant , which is small but not negligible, in the framework of Eckart's theory. In particular, we discuss the capability of the solution in the fulfillment of the three following conditions: (i) the near equilibrium condition, which is assumed in Eckart's theory of non-perfect fluids, (ii) the mathematical stability of the solution under small perturbations, and (iii) the positiveness of the entropy production. We have found that this viscous model can describe the radiation domination era of the CDM model and, at the same time, fulfill the three conditions mentioned by the fulfillment of a single constraint on the bulk viscous coefficient , finding also that this non-singular model has a positive energy density in the infinity past which is infinity hotter with a constant entropy.
arXiv comment12 pages, 5 figures. arXiv admin note: text overlap with arXiv:2202.02362, some typos corrected
References in corpus (34)
- Measurements of Omega and Lambda from 42 High-Redshift Supernovae
- 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
- Properties of singularities in (phantom) dark energy universe
- Inhomogeneous Equation of State of the Universe: Phantom Era, Future Singularity and Crossing the Phantom Barrier
- The Emergent Universe: inflationary cosmology with no singularity
- Observational constraints on dark energy with generalized equations of state
- The Emergent Universe: An Explicit Construction
- Dark Energy and Viscous Cosmology
- Viscous Cosmology for Early- and Late-Time Universe
- Does Bulk Viscosity Create a Viable Unified Dark Matter Model?
- Bulk viscosity driving the acceleration of the Universe
- Viscous dark energy and phantom evolution
- 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
- Bulk Viscosity, Decaying Dark Matter, and the Cosmic Acceleration
- Accelerated and decelerated expansion in a causal dissipative cosmology
- Phantom singularities and their quantum fate: general relativity and beyond
- Viscosity-Induced Crossing of the Phantom Barrier
- Constraints and cosmography of CDM in presence of viscosity
- Analysing dissipative effects in the CDM model
- Microphysical manifestations of viscosity and consequences for anisotropies in the very early universe
- Thermodynamically allowed phantom cosmology with viscous fluid
- Cosmology and thermodynamics of FRW universe with bulk viscous stiff fluid
- Phantom solution in a non-linear Israel-Stewart theory
- Cosmological test on viscous bulk models using Hubble Parameter measurements and type Ia Supernovae data
- Linking little rip cosmologies with regular early universes
- Viscous universe with cosmological constant
- Stability of inflationary solutions driven by a changing dissipative fluid
- Quasi-isotropic cycles and non-singular bounces in a Mixmaster cosmology
- Exact solutions of a Flat Full Causal Bulk viscous FRW cosmological model through factorization
- Study of a viscous WDM model: Near equilibrium condition, entropy production, and cosmological constraints
- Thermodynamic aspects of entropic cosmology with viscosity
- On the stabilization of the Friedmann Big Bang by the shear stresses