Perturbations in Bouncing Cosmological Models

TL;DR

This paper reviews bouncing cosmological models, their perturbation evolution, and potential observational signatures, comparing them with standard inflationary scenarios to explore alternative early universe theories.

Contribution

It provides a comprehensive overview of bouncing models, detailing their perturbation dynamics and observational implications, highlighting differences from inflationary models.

Findings

Bouncing models can produce distinct perturbation spectra.

Potential observational signatures differentiate bouncing models from inflation.

Comparison suggests some bouncing scenarios are compatible with current data.

Abstract

I describe the features and general properties of bouncing models and the evolution of cosmological perturbations on such backgrounds. I will outline possible observational consequences of the existence of a bounce in the primordial Universe and I will make a comparison of these models with standard long inflationary scenarios.