Hubble Parameter in Bulk Viscous Cosmology
A. Tawfik (ECTP & Mti U), H. Mansour (Cairo U), M. Wahba (ECTP & Mti, U)
TL;DR
This paper investigates how bulk viscosity affects the early universe's evolution, using relativistic viscous matter models and approximate solutions to Einstein's equations, revealing significant modifications to cosmological models.
Contribution
It introduces a detailed analysis of bulk viscosity effects on early universe cosmology using advanced viscous fluid models and approximate solutions for the Hubble parameter.
Findings
Bulk viscosity significantly alters early universe dynamics.
Approximate solutions for the Hubble parameter are proposed.
Viscous effects differ between Eckart and Israel-Stewart fluid models.
Abstract
We discuss influences of bulk viscosity on the Early Universe, which is modeled by Friedmann-Robertson-Walker metric and Einstein field equations. We assume that the matter filling the isotropic and homogeneous background is relativistic viscous characterized by ultra-relativistic equations of state deduced from recent lattice QCD simulations. We obtain a set of complicated differential equations, for which we suggest approximate solutions for Hubble parameter . We find that finite viscosity in Eckart and Israel-Stewart fluids would significantly modify our picture about the Early Universe.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsCosmology and Gravitation Theories · Relativity and Gravitational Theory · Advanced Mathematical Theories and Applications