Threshold effects in open-string theory

TL;DR

This paper investigates the one-loop effective gauge-field action in Z2-orbifold compactifications of type-I string theory, revealing that for non-abelian groups, threshold effects are UV finite and described by a six-dimensional field theory.

Contribution

It demonstrates that non-abelian threshold effects in this context are UV finite and can be expressed through six-dimensional field theory calculations.

Findings

Threshold effects are ultraviolet finite.

Threshold effects are described by six-dimensional field theory.

Applicable to Z2-orbifold compactifications of type-I theory.

Abstract

We analyze the one-loop effective gauge-field action in $Z_2$-orbifold compactifications of type-I theory. We show how, for non-abelian group factors, the threshold effects are ultraviolet finite though given entirely by a six-dimensional field theory expression.