English

Primordial perturbations in a non singular bouncing universe model

High Energy Physics - Theory 2009-11-07 v1 Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

Abstract

We construct a simple non singular cosmological model in which the currently observed expansion phase was preceded by a contraction. This is achieved, in the framework of pure general relativity, by means of a radiation fluid and a free scalar field having negative energy. We calculate the power spectrum of the scalar perturbations that are produced in such a bouncing model and find that, under the assumption of initial vacuum state for the quantum field associated with the hydrodynamical perturbation, this leads to a spectral index n=-1. The matching conditions applying to this bouncing model are derived and shown to be different from those in the case of a sharp transition. We find that if our bounce transition can be smoothly connected to a slowly contracting phase, then the resulting power spectrum will be scale invariant.

Keywords

Cite

@article{arxiv.hep-th/0203013,
  title  = {Primordial perturbations in a non singular bouncing universe model},
  author = {Patrick Peter and Nelson Pinto-Neto},
  journal= {arXiv preprint arXiv:hep-th/0203013},
  year   = {2009}
}

Comments

11 pages, RevTeX 4, 8 figures, submitted to Phys. Rev. D

R2 v1 2026-07-22T15:09:25.985Z