On possible origin of an anisotropy in the speed of light in vacuum

TL;DR

This paper explores how a spacetime foam filled with virtual wormholes can cause anisotropy in the speed of light, potentially leading to superluminal light velocities and dispersion effects.

Contribution

It introduces a model linking virtual wormhole distributions to anisotropic light speed and anomalous dispersion in vacuum.

Findings

Speed of light becomes anisotropic due to wormhole distribution

Vacuum may exhibit anomalous dispersion with superluminal light velocities

External fields influence wormhole distribution and light propagation

Abstract

We assume the spacetime foam picture in which vacuum is filled with virtual wormholes. In the presence of an external field the distribution of wormholes changes. We consider an anisotropic distribution of wormholes and analyze its relation to the speed of light. We show that speed of light acquires an anisotropic character and save the normal dispersion a gas of virtual wormholes may possess also an anomalous dispersion, i.e., when the light velocity exceeds that in the vacuum.