`Blowing up' D-branes on Non-supersymmetric Cycles

TL;DR

This paper investigates the stability and decay of D-branes on non-supersymmetric cycles in K3 surfaces, revealing phase transitions triggered by non-geometric blow-up modes within conformal field theory.

Contribution

It provides an exact CFT analysis of D-branes on non-supersymmetric cycles and characterizes their stability regions and decay processes under blow-up mode perturbations.

Findings

Identified stability regions for D-branes on non-supersymmetric cycles.

Described decay of non-supersymmetric D-branes into supersymmetric pairs.

Linked phase transitions to non-geometric fluxes in the moduli space.

Abstract

In the orbifold limit of K3, one can give exact conformal field theory description of D-branes wrapped on certain non-supersymmetric cycles of K3. We study the effect of switching on the `non-geometric blow up modes' corresponding to anti-symmetric tensor gauge field flux through the 2-cycles on these D-branes. Working to first order in the blow up parameter, we determine the region of the moduli space in which these D-branes are stable. Across the boundary of this region, the D-brane wrapped on the non-supersymmetric cycle decays to a pair of D-branes, each wrapped on a supersymmetric cycle, via a second order phase transition.