Non-Supersymmetric String Theory

TL;DR

This paper explores non-supersymmetric string backgrounds created through space-time fermion parity twists, proposing a gauge theory-based non-perturbative framework, revealing a novel inflation mechanism and complex tachyon condensation outcomes.

Contribution

It introduces a gauge theory approach to define non-supersymmetric string theories non-perturbatively, including new insights into inflation and tachyon dynamics.

Findings

Reproduces perturbative string spectrum

Proposes a gauge theory non-perturbative formulation

Identifies a new inflation mechanism

Abstract

A class of non-supersymmetric string backgrounds can be constructed using twists that involve space-time fermion parity. We propose a non-perturbative definition of string theory in these backgrounds via gauge theories with supersymmetry softly broken by twisted boundary conditions. The perturbative string spectrum is reproduced, and qualitative effects of the interactions are discussed. Along the way, we find an interesting mechanism for inflation. The end state of closed string tachyon condensation is a highly excited state in the gauge theory which, in all likelihood, does not have a geometric interpretation.