On a new approach for constructing wormholes in Einstein–Born–Infeld gravity

Jin Young Kim,Mu-In Park

doi:10.1140/epjc/s10052-016-4497-7

Abstract

We study a new approach for the wormhole construction in Einstein-Born-Infeld gravity, which does not require exotic matters in the Einstein equation. The Born-Infeld field equation is not modified from "coordinate independent" conditions of continuous metric tensor and its derivatives, even though the Born-Infeld fields have discontinuities in their derivatives at the throat in general. We study the relation of the newly introduced conditions with the usual continuity equation for the energy-momentum tensor and the gravitational Bianchi identity. We find that there is no violation of energy conditions for the Born-Infeld fields contrary to the usual approaches. The exoticity of energy-momentum tensor is not essential for sustaining wormholes. Some open problems are discussed.

Highlights

Wormholes are non-singular space-time structures connecting two different universes or parts of the same universe [1]
Even when we look for wormhole solutions without the explicit introduction of exotic matters, we need some effective matter terms in the Einstein equation which play the role of exotic matters
We have studied a new approach to construct a natural wormhole geometry in EBI gravity without introducing additional exotic matters at the throat

Summary

Introduction

Wormholes are non-singular space-time structures connecting two (or more) different universes or parts of the same universe [1]. We do not have a priori reason to choose only one of the two options so that we can consider both options This is in contrast to the Morris– Thorne-type traversable wormholes, which cannot co-exist with the solutions of black holes with the same conserved charges. For the Kerr black hole in GR, there are more metric functions and there is no solution for the throat where all the metric functions join smoothly simultaneously This implies that the wormhole throat in the spherically symmetric configurations could be destroyed by adding other conserved charges. 3, we study the natural wormhole geometry as the solution of the Einstein equation without introducing additional matters at the throat based on the construction sketched in Sect.

Black hole solutions in Einstein–Born–Infeld gravity

Construction of natural wormhole solutions

Energy conditions

Discussion