Indications of causal set cosmology

TL;DR

This paper explores how a universe with large-scale homogeneity and isotropy can naturally emerge from causal set cosmology without fine-tuning, due to a renormalization group effect linked to cosmic cycles.

Contribution

It demonstrates that large, homogeneous universes can arise naturally in causal set cosmology through a renormalization process, reducing the need for fine-tuning of fundamental parameters.

Findings

Large homogeneous universes can emerge without fine-tuning.

A renormalization group effect drives the emergence of large-scale structure.

Cosmic cycles facilitate natural emergence of universe properties.

Abstract

Within the context of a recently proposed family of stochastic dynamical laws for causal sets, one can ask whether the universe might have emerged from the quantum-gravity era with a large enough size and with sufficient homogeneity to explain its present-day large-scale structure. In general, such a scenario would be expected to require the introduction of very large or very small fundamental parameters into the theory. However, there are indications that such ``fine tuning'' is not necessary, and a large homogeneous and isotropic cosmos can emerge naturally, thanks to the action of a kind of renormalization group associated with cosmic cycles of expansion and re-contraction.