Braneworlds in six dimensions: new models with bulk scalars

TL;DR

This paper constructs six-dimensional brane-world models with bulk scalars, including phantom and Brans-Dicke types, exploring their geometries, compactifications, and matter field localization.

Contribution

It introduces new six-dimensional brane models with non-conventional bulk scalars, analyzing their geometries and matter localization properties.

Findings

Found geometries with 4-branes and compact on-brane dimensions.

Constructed models with 3-branes at conical singularities.

Analyzed localization of scalar, fermion, graviton, and vector fields.

Abstract

Six dimensional bulk spacetimes with 3-- and 4--branes are constructed using certain non--conventional bulk scalars as sources. In particular, we investigate the consequences of having the phantom (negative kinetic energy) and the Brans--Dicke scalar in the bulk while obtaining such solutions. We find geometries with 4--branes with a compact on--brane dimension (hybrid compactification) which may be assumed to be small in order to realize a 3--brane world. On the other hand, we also construct, with similar sources, bulk spacetimes where a 3--brane is located at a conical singularity. Furthermore, we investigate the issue of localization of matter fields (scalar, fermion, graviton, vector) on these 3-- and 4--branes and conclude with comments on our six dimensional models.