Cosmic String Nucleation near the Inflationary Phase Boundary

TL;DR

This paper studies the conditions under which circular cosmic strings can nucleate during inflationary phases, showing that expansion alone is not enough for their quantum nucleation.

Contribution

It demonstrates that an inflationary expanding phase is necessary but not sufficient for quantum nucleation of circular cosmic strings.

Findings

Inflationary expansion is necessary for string nucleation.

Quantum nucleation requires more than just expansion.

Nucleation occurs during specific transition phases.

Abstract

We investigate the nucleation of circular cosmic strings in models of generalized inflationary universes with an accelerating scale factor. We consider toy cosmological models of a smooth inflationary exit and transition into a flat Minkowski spacetime. Our results establish that an inflationary expanding phase is necessary but not sufficient for quantum nucleation of circular cosmic strings to occur.