Four-Dimensional Supergravities from Five-Dimensional Brane Worlds

TL;DR

This paper derives the explicit four-dimensional supergravity action from a five-dimensional brane world model, elucidating the role of bulk scalars and supersymmetry breaking in stabilizing the interbrane distance.

Contribution

It provides a detailed derivation of the 4D effective supergravity from 5D models with branes, including the effects of odd parity scalars and supersymmetry breaking mechanisms.

Findings

Explicit 4D supergravity action derived from 5D model.

Bulk scalars induce effective potential for radion.

Supersymmetry breaking stabilizes interbrane distance.

Abstract

We give the explicit form of the four dimensional effective supergravity action, which describes low energy physics of the Randall-Sundrum model with moduli fields in the bulk and charged chiral matter living on the branes. The relation between 5d and 4d physics is explicit: the low energy action is derived from the compactification of a locally supersymmetric model in five dimension. The presence of odd $Z_2$ parity scalars in the bulk gives rise to effective potential for the radion in four dimensions. We describe the mechanism of supersymmetry breaking mediation, which relies on non-trivial configuration of these $Z_2$-odd bulk fields. Broken supersymmetry leads to stabilization of the interbrane distance.