String production at the level of effective field theory

TL;DR

This paper investigates string pair creation in dynamic backgrounds using effective field theory, exploring potential cosmological implications such as the role of excited strings in preheating when string tension is sufficiently low.

Contribution

It introduces an effective field theory approach to analyze string pair creation and discusses its possible significance in early universe cosmology.

Findings

Excited strings could influence preheating if string tension is below the Planck scale.

Effective field theory provides a useful framework for studying string production in cosmological settings.

String pair creation may have observable consequences in the early universe.

Abstract

Pair creation of strings in time-dependent backgrounds is studied from an effective field theory viewpoint, and some possible cosmological applications are discussed. Simple estimates suggest that excited strings may have played a significant role in preheating, if the string tension as measured in four-dimensional Einstein frame falls a couple of orders of magnitude below the four-dimensional Planck scale.