Gauge-Invariant Couplings of Noncommutative Branes to Ramond-Ramond Backgrounds

TL;DR

This paper develops gauge-invariant couplings of noncommutative D-branes to varying Ramond-Ramond fields, revealing identities and a Seiberg-Witten map, and extends these to include scalars and unstable branes.

Contribution

It introduces a new formulation of noncommutative D-brane couplings to RR fields, including a Seiberg-Witten map and extensions to scalars and unstable branes.

Findings

Derived couplings expressed via *n products with open Wilson lines.

Established equivalence between noncommutative and commutative couplings.

Proposed RR couplings for unstable non-BPS branes.

Abstract

We derive the couplings of noncommutative D-branes to spatially varying Ramond-Ramond fields, extending our earlier results in hep-th/0009101. These couplings are expressed in terms of *n products of operators involving open Wilson lines. Equivalence of the noncommutative to the commutative couplings implies interesting identities as well as an expression for the Seiberg-Witten map that was previously conjectured. We generalise our couplings to include transverse scalars, thereby obtaining a Seiberg-Witten map relating commutative and noncommutative descriptions of these scalars. RR couplings for unstable non-BPS branes are also proposed.