Ring Wormholes in D-Dimensional Einstein and Dilaton Gravity

TL;DR

This paper explores static, traversible wormhole solutions in D-dimensional Einstein and dilaton gravity, analyzing their properties, regularity conditions, and physical characteristics like mass and length scale.

Contribution

It presents new exact solutions of Einstein-Abelian gauge-dilaton equations describing regular, symmetric wormholes with specific mass and length scale properties.

Findings

Regular, symmetric wormholes have positive masses from both sides.

In the large charge limit, the wormhole length scale is about Q^2/M.

Some wormholes are globally regular with no curvature singularities.

Abstract

On the basis of exact solutions to the Einstein-Abelian gauge-dilaton equations in $D$-dimensional gravity, the properties of static axial configurations are discussed. Solutions free of curvature singularities are selected; they can be attributed to traversible wormholes with cosmic string-like singularities at their necks. In the presence of an electromagnetic field some of these wormholes are globally regular, the string-like singularity being replaced by a set of twofold branching points. Consequences of wormhole regularity and symmetry conditions are discussed. In particular, it is shown that (i) regular, symmetric wormholes have necessarily positive masses as viewed from both asymptotics and (ii) their characteristic length scale in the big charge limit ($GM^2 \ll Q^2$) is of the order of the ``classical radius" $Q^2/M$.