All Universes Great and Small

TL;DR

This paper explores how a compact universe topology impacts the naturalness and likelihood of observed cosmic features like isotropy and flatness, providing a broader understanding of cosmological models.

Contribution

It identifies the most general cosmological models with compact space and analyzes their implications for universe naturalness and initial conditions.

Findings

Compact topology significantly alters universe naturalness assessments

Most general models with compact space are characterized

Implications for initial conditions and observed universe features

Abstract

If the topology of the universe is compact we show how it significantly changes our assessment of the naturalness of the observed structure of the universe and the likelihood of its present state of high isotropy and near flatness arising from generic initial conditions. We also identify the most general cosmological models with compact space.