English

Dynamics of Robertson-Walker spacetimes with diffusion

General Relativity and Quantum Cosmology 2015-06-22 v2 Cosmology and Nongalactic Astrophysics

Abstract

We study the dynamics of spatially homogeneous and isotropic spacetimes containing a fluid undergoing microscopic velocity diffusion in a cosmological scalar field. After deriving a few exact solutions of the equations, we continue by analyzing the qualitative behavior of general solutions. To this purpose we recast the equations in the form of a two dimensional dynamical system and perform a global analysis of the flow. Among the admissible behaviors, we find solutions that are asymptotically de-Sitter both in the past and future time direction and which undergo accelerated expansion at all times.

Keywords

Cite

@article{arxiv.1409.4400,
  title  = {Dynamics of Robertson-Walker spacetimes with diffusion},
  author = {Artur Alho and Simone Calogero and Maria P. Machado Ramos and Ana J. Soares},
  journal= {arXiv preprint arXiv:1409.4400},
  year   = {2015}
}

Comments

19 pages, 4 figures. Matches final version

R2 v1 2026-06-22T05:57:14.747Z