Non-BPS D-branes and M-theory

TL;DR

This paper explores non-BPS D-branes in a dual pair of string theories, showing they carry K-theory charges and can be understood via M-theory, with dual states consistent with M-theory descriptions.

Contribution

It demonstrates that non-BPS D-branes in an asymmetric orbifold and orientifold setting carry K-theory charges and can be interpreted through M-theory homology classes.

Findings

Non-BPS D-branes carry non-trivial K-theory charges.

Dual partners of these D-branes are consistent with M-theory predictions.

The relations between dual states align with M-theory descriptions.

Abstract

A dual pair of supersymmetric string theories that involves an asymmetric orbifold and an orientifold of Type II is considered. The D-branes of the orbifold theory (that were recently determined by Gutperle) are all non-BPS and do not carry any conserved gauge charges. It is shown that they carry non-trivial K-theory charges, and that they can be understood in terms of branes wrapping certain homology classes of the M-theory compactification. Using the adiabatic argument, dual partners of some of these non-BPS D-branes are proposed. The relations between these dual states are found to be in agreement with the M-theory description of the D-branes.