String Supported Wormhole Spacetimes and Causality Violations

TL;DR

This paper constructs a static wormhole model using Schwarzschild particles connected by strings, demonstrating that causality violations can occur when the wormhole mouths have different masses.

Contribution

It introduces a new static wormhole solution based on Schwarzschild particles and analyzes conditions leading to causality violations.

Findings

Causality violations occur when wormhole mouths have different masses.

A method to approximate the wormhole spacetime with small matching errors.

Wormhole construction relies on matching timelike surfaces around particles.

Abstract

We construct a static axisymmetric wormhole from the gravitational field of two Schwarzschild particles which are kept in equilibrium by strings (ropes) extending to infinity. The wormhole is obtained by matching two three-dimensional timelike surfaces surrounding each of the particles and thus spacetime becomes non-simply connected. Although the matching will not be exact in general it is possible to make the error arbitrarily small by assuming that the distance between the particles is much larger than the radius of the wormhole mouths. Whenever the masses of the two wormhole mouths are different, causality violating effects will occur.