Dimensional Reduction for D3-brane Moduli

TL;DR

This paper derives the 4D effective theory for D3-branes in warped Calabi-Yau compactifications, including brane motion effects, extending previous results and relevant for string phenomenology and cosmology.

Contribution

It provides a first-principles derivation of the low-energy effective theory including brane dynamics beyond the probe approximation.

Findings

Derived the moduli space metric for D3-brane positions

Included effects of D3-brane motion in warped backgrounds

Extended previous results on D3-brane effective theories

Abstract

Warped string compactifications are central to many attempts to stabilize moduli and connect string theory with cosmology and particle phenomenology. We present a first-principles derivation of the low-energy 4D effective theory from dimensional reduction of a D3-brane in a warped Calabi-Yau compactification of type IIB string theory with imaginary self-dual 3-form flux, including effects of D3-brane motion beyond the probe approximation, and find the metric on the moduli space of brane positions, the universal volume modulus, and axions descending from the 4-form potential. As D3-branes may be considered as carrying either electric or magnetic charges for the self-dual 5-form field strength, we present calculations in both duality frames. Our results are consistent with, but extend significantly, earlier results on the low-energy effective theory arising from D3-branes in string compactifications.