Bouncing cosmologies in geometries with positively curved spatial sections

TL;DR

This paper explores bouncing cosmologies within positively curved geometries, demonstrating their ability to produce nearly flat power spectra compatible with observations during a quasi-matter domination phase.

Contribution

It reconstructs bouncing cosmologies with positive spatial curvature in General Relativity, showing their compatibility with observational data and their potential to produce realistic power spectra.

Findings

Nearly flat power spectrum of curvature fluctuations

Spectral index and running compatible with data

Bouncing cosmologies with positive curvature are viable

Abstract

Background boucing cosmologies in the framework of General Relativity, driven by a single scalar field filling the Universe, and with a quasi-matter domination period, i.e., depicting the so-called Matter Bounce Scenario, are reconstructed for geometries with positive spatial curvature. These cosmologies lead to a nearly flat power spectrum of the curvature fluctuations in co-moving coordinates for modes that leave the Hubble radius during the quasi-matter domination period, and whose spectral index and its running, which are related with the effective Equation of State parameter given by the quotient of the pressure over the energy density, are compatible with observational data.