Brane solutions in strings with broken supersymmetry and dilaton tadpoles

TL;DR

This paper investigates non-supersymmetric string theories with dilaton tadpoles, finding static nine-dimensional solutions with finite Planck and gauge constants, indicating spontaneous compactification of ten-dimensional string models.

Contribution

It determines maximally symmetric backgrounds for specific non-supersymmetric string theories, revealing a spontaneous compactification mechanism despite dilaton tadpoles.

Findings

Static solutions with nine-dimensional Poincaré symmetry

Finite 9D Planck and Yang-Mills constants

Ten-dimensional manifold with two boundaries

Abstract

The tachyon-free nonsupersymmetric string theories in ten dimensions have dilaton tadpoles which forbid a Minkowski vacuum. We determine the maximally symmetric backgrounds for the $USp(32)$ Type I string and the $SO(16)\times SO(16)$ heterotic string. The static solutions exhibit nine dimensional Poincar\'e symmetry and have finite 9D Planck and Yang-Mills constants. The low energy geometry is given by a ten dimensional manifold with two boundaries separated by a finite distance which suggests a spontaneous compactification of the ten dimensional string theory.