Bouncing alternatives to inflation

TL;DR

This paper explores bouncing cosmological models as alternatives to inflation, emphasizing the importance of ruling out these options through comparison with observational data to understand the early universe.

Contribution

It provides a focused analysis on bouncing models as viable alternatives to inflation and discusses their potential observational consequences.

Findings

Bouncing models can replicate some inflationary predictions.

Comparison with data can distinguish bouncing scenarios from inflation.

The paper highlights the need to test all early universe models against observations.

Abstract

Although the inflationary paradigm is the most widely accepted explanation for the current cosmological observations, it does not necessarily correspond to what actually happened in the early stages of our Universe. To decide on this issue, two paths can be followed: first, all the possible predictions it makes must be derived thoroughly and compared with available data, and second, all imaginable alternatives must be ruled out. Leaving the first task to all other contributors of this volume, we concentrate here on the second option, focusing on the bouncing alternatives and their consequences.