Casimir force induced on a plane by an impenetrable flux tube of finite radius

TL;DR

This paper investigates the Casimir force induced on a plane by an impenetrable magnetic flux tube of finite radius, showing that vacuum polarization causes a macroscopic force as the tube radius increases.

Contribution

It introduces a model with a finite-radius magnetic flux tube and analyzes the resulting vacuum polarization effects on a charged scalar field.

Findings

Vacuum polarization induces a force on the flux tube.

The force depends on the tube radius and magnetic flux.

Macroscopic forces can arise from quantum vacuum effects.

Abstract

A perfectly reflecting (Dirichlet) boundary condition at the edge of an impenetrable magnetic-flux-carrying tube of nonzero transverse size is imposed on the charged massive scalar matter field which is quantized outside the tube on a plane which is transverse to the tube. We show that the vacuum polarization effects outside the tube give rise to a macroscopic force acting at the increase of the tube radius (if the magnetic flux is held steady).