Actions for Curved Branes

TL;DR

This paper generalizes brane actions by making metrics dynamical, leading to models where gauge fields are confined to the brane while gravity propagates in the bulk, including nonsymmetric and conformal gravity scenarios.

Contribution

It introduces a new class of brane actions with dynamical metrics, enabling the study of brane world and cosmological models with various gravity theories on the brane.

Findings

Nonsymmetric gravity propagates on the brane with a nonsymmetric metric.

Conformal (Weyl) gravity propagates on the brane with symmetric metrics.

Gauge fields are confined to the brane while gravity extends into the bulk.

Abstract

The nondeterminantal forms of the Born-Infeld and related brane actions in which the gauge fields couple to both an induced metric and an intrinsic metric are generalised by letting either or both metrics be dynamical. The resulting actions describe ` brane world' and cosmological scenarios in which the gauge fields are confined to the brane, while gravity propagates in both the world-volume and the bulk. In particular, for actions involving a nonsymmetric ` metric', nonsymmetric gravity propagates on the worldvolume. For 3-branes with a symmetric metric, conformal (Weyl) gravity propagates on the worldvolume and has conformally invariant couplings to the gauge fields.