English

Matter creation in a nonsingular bouncing cosmology

General Relativity and Quantum Cosmology 2014-09-10 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

Abstract

We examine reheating in the two-field matter bounce cosmology. In this model, the universe evolves from a matter-dominated phase of contraction to an Ekpyrotic phase of contraction before the nonsingular bounce. The Ekpyrotic phase frees the model from unwanted anisotropies, but leaves the universe cold and empty of particles after the bounce. For this reason, we explore two particle production mechanisms which take place during the course of the cosmological evolution: Parker particle production where the matter field couples only to gravity and particle creation via interactions between the matter field and the bounce field. Although we show that both mechanisms can produce particles in this model, we find that Parker particle production is sufficient to reheat the universe to high temperatures. Thus there is {\it{a priori}} no need to add an interaction term to the Lagrangian of the model. Still, particle creation via interactions can contribute to the formation of matter and radiation, but only if the coupling between the fields is tuned to be large.

Keywords

Cite

@article{arxiv.1406.6049,
  title  = {Matter creation in a nonsingular bouncing cosmology},
  author = {Jerome Quintin and Yi-Fu Cai and Robert H. Brandenberger},
  journal= {arXiv preprint arXiv:1406.6049},
  year   = {2014}
}

Comments

14 pages, 2 figures. Replaced to match published version

R2 v1 2026-06-22T04:45:12.972Z