Rotating traversable wormholes

TL;DR

This paper explores rotating traversable wormholes, generalizing static models, analyzing their energy conditions, geodesic properties, and the potential for ergoregions, contributing to theoretical understanding of such exotic spacetime structures.

Contribution

It introduces explicit classes of rotating wormholes extending static models and examines their energy conditions, geodesic behavior, and ergoregion presence.

Findings

Rotating wormholes generally violate the null energy condition at the throat.

Certain geodesics can pass through the wormhole without encountering energy-condition-violating matter.

An ergoregion may exist surrounding the wormhole throat.

Abstract

The general form of a stationary, axially symmetric traversable wormhole is discussed. This provides an explicit class of rotating wormholes that generalize the static, spherically symmetric ones first considered by Morris and Thorne. In agreement with general analyses, it is verified that such a wormhole generically violates the null energy condition at the throat. However, for suitable model wormholes, there can be classes of geodesics falling through it which do not encounter any energy-condition-violating matter. The possible presence of an ergoregion surrounding the throat is also noted.