Dirac actions for D-branes on backgrounds with fluxes

TL;DR

This paper derives a simplified Dirac-like fermionic action for D-branes in flux backgrounds, generalizing the standard form and revealing how fluxes deform the fermionic dynamics in supergravity settings.

Contribution

It introduces a new, simplified Dirac-like fermionic action for D-branes in flux backgrounds, extending previous models to more general supergravity environments.

Findings

Derived a new Dirac-like fermionic action for D-branes with fluxes.

Showed how fluxes deform the Dirac operator in the fermionic action.

Revealed a geometric redefinition to restore the canonical form.

Abstract

The understanding of the fermionic sector of the worldvolume D-brane dynamics on a general background with fluxes is crucial in several branches of string theory, like for example the study of nonperturbative effects or the construction of realistic models living on D-branes. In this paper we derive a new simple Dirac-like form for the bilinear fermionic action for any Dp-brane in any supergravity background, which generalizes the usual Dirac action valid in absence of fluxes. A nonzero world-volume field strength deforms the usual Dirac operator in the action to a generalized non-canonical one. We show how the canonical form can be re-established by a redefinition of the world-volume geometry.