Birth of de Sitter Universe from time crystal

TL;DR

This paper demonstrates that a specific Horndeski theory extension can model a time crystal Universe, which can nucleate a de Sitter Universe via tunneling, providing a potential past completion of inflation.

Contribution

It introduces a novel connection between time crystal universes and de Sitter space within a Horndeski framework, extending instanton concepts to cosmology.

Findings

Time crystal Universe can nucleate from flat space.

De Sitter Universe can emerge via tunneling from the time crystal.

Provides a new perspective on the origin of inflationary universes.

Abstract

We show that a simple sub-class of Horndeski theory can describe a time crystal Universe. The time crystal Universe can be regarded as a baby Universe nucleated from a flat space, which is mediated by an extension of Giddings-Strominger instanton in a 2-form theory dual to the Horndeski theory. Remarkably, when a cosmological constant is included, de Sitter Universe can be created by tunneling from the time crystal Universe. It gives rise to a past completion of an inflationary Universe.