Dirac actions for D-branes on backgrounds with fluxes

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.

Inflation and String Theory

“…The sufficient condition (3.112) is unmodified by the presence of flux, but in flux backgrounds the necessary condition (3.111) is modified and becomes less restrictive [334,[343][344][345][346][347][348]. Couplings to flux can give mass to (some of the) deformations of Euclidean D3-branes, and of D7-branes, counted by h 0,2 .…”

“…Couplings to flux can give mass to (some of the) deformations of Euclidean D3-branes, and of D7-branes, counted by h 0,2 . Generalizations of (3.111) to backgrounds with flux, and further consistency conditions, are described in [334,[343][344][345][346][347][348][349][350] and reviewed in [338,351].…”

D 3 ¯ $$ \overline{\mathrm{D}3} $$ and dS

“…In the gauge (2.14) θ 1 and θ 2 are not proportional, and our gauge therefore does not belong to that class of gauges. However, we will use below the construction of the classical (not gauge-fixed) action quadratic in θ for the D3 and D3 brane, based on the superspace of d = 11 supergravity for the M2 brane background and a T-duality as in [39,46,47].…”

A landscape of field theories

“…We describe the fixing of kappa symmetry and the emergence of a worldvolume field theory, the preserved world-volume supersymmetries, and we examine some aspects of the resulting equations of motion. Some of the early work on the coupling of fluxes to branes appears in [11,12] and for Euclidean M5-branes in [13]. See also the recent work [14] which also discusses some of the aspects for supersymmetric brane configurations in flux backgrounds.…”