A note on the torsion dependence of D-brane RR couplings

TL;DR

This paper investigates how torsion in the background affects the RR couplings of D-branes, revealing that torsion can modify these couplings even in simple configurations, by replacing curvature terms with torsion-inclusive generalizations.

Contribution

It demonstrates the torsion dependence of D-brane RR couplings and generalizes the curvature terms to include torsion effects in specific trivial bundle cases.

Findings

Torsion components can influence RR couplings even in simple D-brane setups.

Replacing standard curvature with torsion-inclusive curvature generalizes the couplings.

Torsion effects are significant when tangent or normal bundles are trivial.

Abstract

The dependence on the torsion H=db of the Wess-Zumino couplings of D-branes that are trivially embedded in space-time is studied. We show that even in this simple set-up some torsion components can be turned on, with a non-trivial effect on the RR couplings. In the special cases in which either the tangent or the normal bundle are trivial, the torsion dependence amounts to substitute the standard curvature with its generalization in the presence of torsion, in the usual couplings involving the roof genus A.