Localization of Gauge Fields and Monopole Tunnelling

TL;DR

This paper investigates how gauge fields can be localized on a brane via confinement mechanisms, revealing that monopole tunnelling induces weak confinement at large distances, with implications for higher-dimensional theories and cosmology.

Contribution

It demonstrates that monopole tunnelling causes weak confinement of localized gauge fields on a brane, clarifying the large-distance physics and potential phenomenological consequences.

Findings

Localized gauge fields require bulk confinement.

Monopole tunnelling induces weak confinement at large distances.

Implications for higher-dimensional models and cosmology.

Abstract

We study the dynamical localization of a massless gauge field on a lower-dimensional surface (2-brane). In flat space, the necessary and sufficient condition for this phenomenon is the existence of confinement in the bulk. The resulting configuration is equivalent to a dual Josephson junction. This duality leads to an interesting puzzle, as it implies that a localized massless theory, even in the Abelian case, must become confining at exponentially large distances. Through the use of topological arguments we clarify the physics behind this large-distance confinement and identify the instantons of the brane world-volume theory that are responsible for its appearance. We show that they correspond to the (condensed) bulk magnetic charges (monopoles), that occasionally tunnel through the brane and induce weak confinement of the brane theory. We consider the possible generalization of this effect to higher dimensions and discuss phenomenological bounds on the confinement of electric charges at exponentially large distances within our Universe.