Gauge Unification via Stable Brane Recombination

TL;DR

This paper explores how transitions between parallel and intersecting branes on a torus can lead to gauge symmetry breaking and unification, emphasizing supersymmetry preservation and brane dynamics.

Contribution

It introduces a framework for understanding brane recombination transitions that preserve supersymmetry and unify gauge couplings in string theory models.

Findings

Existence of supersymmetry-preserving brane transition

Gauge unification achieved through brane dynamics

Intersecting brane models as broken phases of Type I theory

Abstract

We study the transition between parallel and intersecting branes on a torus. Spontaneous symmetry breaking of nonabelian gauge symmetry is understood as brane separation, and a more general intermediate deformation is discussed. We argue that there exists supersymmetry preserving transition and we can always have parallel branes as a final state. The transition is interpreted due to dynamics of the F- and D-string junctions and their generalization to (F, D$p$) bound states. The gauge group and coupling unification is achieved, also as a result of supersymmetry. From the tadpole cancelation condition, we naturally have some class of intersecting brane models as broken phases of Type I theory with SO(32) gauge group.