Towards traversable wormholes from force-free plasmas

TL;DR

This paper explores the theoretical possibility of creating traversable wormholes using negative Casimir energy from Alfven wave modes in force-free plasmas near magnetically charged black holes, but finds size restrictions limit their practicality.

Contribution

It introduces a novel approach to constructing traversable wormholes using force-free plasma physics and analyzes the limitations imposed by scalar field behavior near black holes.

Findings

Wormhole size is strongly restricted by scalar field behavior.

Negative Casimir energy from Alfven modes can theoretically support wormholes.

Practical large-scale wormholes are unlikely due to size constraints.

Abstract

The near-horizon region of magnetically charged black holes can have very strong magnetic fields. A useful low-energy effective theory for fluctuations of the fields, coupled to electrically charged particles, is force-free electrodynamics. The low energy collective excitations include a large number of Alfven wave modes, which have a massless dispersion relation along the field worldlines. We attempt to construct traversable wormhole solutions using the negative Casimir energy of the Alfven wave modes, analogously to the recent construction using charged massless fermions. The behaviour of massless scalars in the near-horizon region implies that the size of the wormholes is strongly restricted and cannot be made large, even though the force free description is valid in a larger regime.