Kinetic gravity braiding wormhole geometries

TL;DR

This paper explores how kinetic gravity braiding (KGB) scalar-tensor models can support a variety of traversable wormhole geometries, including asymptotically flat and anti-de Sitter solutions, through analytical and numerical methods.

Contribution

It provides the full gravitational field equations for KGB-supported wormholes and demonstrates the existence of diverse solutions under specific conditions.

Findings

KGB models can sustain traversable wormholes.

Solutions include asymptotically flat and anti-de Sitter geometries.

The theory exhibits a rich structure of wormhole solutions.

Abstract

An interesting class of scalar-tensor models, denoted by kinetic gravity braiding (KGB), has recently been proposed. These models contain interactions of the second derivatives of the scalar field that do not lead to additional degrees of freedom and exhibit peculiar features, such as an essential mixing of the scalar $\phi$ and tensor kinetic $X$ terms. In this work, we consider the possibility that wormhole geometries are sustained by the KGB theory. More specifically, we present the full gravitational field equations in a static and spherically symmetric traversable wormhole background, and outline the general constraints at the wormhole throat, imposed by the flaring-out conditions. Furthermore, we present a plethora of analytical and numerical wormhole solutions by considering particular choices of the KGB factors. The analysis explicitly demonstrates that the KGB theory exhibits a rich structure of wormhole geometries, ranging from asymptotically flat solutions to asymptotically anti-de Sitter spacetimes.