On the effective action of stable non-BPS branes

TL;DR

This paper investigates the effective world-volume action of stable non-BPS branes in Type II string theories compactified on K3, revealing their potential chiral nature and anomaly cancellation mechanisms similar to BPS branes.

Contribution

It demonstrates that stable non-BPS branes can have a chiral effective theory with anomaly inflow, aligning with their interpretation as BPS branes on non-supersymmetric cycles.

Findings

Effective action can be chiral for these branes.

Anomalies are canceled via inflow with couplings to twisted R-R fields.

Results support the BPS interpretation of non-BPS branes on K3.

Abstract

We study the world-volume effective action of stable non-BPS branes present in Type II theories compactified on K3. In particular, by exploiting the conformal description of these objects available in the orbifold limit, we argue that their world-volume effective theory can be chiral. The resulting anomalies are cancelled through the usual inflow mechanism provided there are anomalous couplings, similar to those of BPS branes, to the twisted R-R fields. We also show that this result is in agreement with the conjectured interpretation of these non-BPS configurations as BPS branes wrapped on non-supersymmetric cycles of the K3.