On new gravitational instantons describing creation of brane-worlds

TL;DR

This paper introduces a new class of regular 5-dimensional gravitational instantons with negative cosmological constant, describing wormholes and brane-world scenarios that can lead to inflating or multitemporal branes.

Contribution

It presents a novel regular instantonic solution in 5D cosmological models with scalar fields and negative cosmological constant, enabling new brane-world constructions.

Findings

Found regular instantonic solutions free from singularities.

Constructed compactified brane-world instantons with various topologies.

Demonstrated analytical continuation leads to inflating or multitemporal branes.

Abstract

By considering 5--dimensional cosmological models with a bulk filled with a pressureless scalar field; equivalently dust matter, and a negative cosmological constant, we have found a regular instantonic solution which is free from any singularity at the origin of the extra--coordinate. This instanton describes 5--dimensional asymptotically anti de Sitter wormhole, when the bulk has a topology R times S^4. Compactified brane-world instantons which are built up from such instantonic solution describe either a single brane or a string of branes. Their analytical continuation to the pseudo--Riemannian metric can give rise to either 4-dimensional inflating branes or solutions with the same dynamical behaviour for extra--dimension and branes, in addition to multitemporal solutions. Dust brane-world models with arbitrary dimensions (D >= 5) as well as other spatial topologies are also briefly discussed.