On the possibility of classical vacuum polarization and magnetization

TL;DR

This paper explores the theoretical possibility that gravity can induce classical polarization and magnetization in vacuum, challenging standard assumptions and suggesting new ways to detect spacetime geometries through electromagnetic effects.

Contribution

It introduces a formalism using differential forms to describe how gravity may cause vacuum polarization and magnetization, offering novel perspectives on spacetime and electromagnetic interactions.

Findings

Gravity may induce dielectric and magnetic responses in vacuum.

Differential forms provide a clear framework for this analysis.

Potential for new detection methods of spacetime geometries.

Abstract

It is common practice to take for granted the equality (up to the constant $\varepsilon_0$) of the electric displacement ($\bf{D}$) and electric ($\bf{E}$) field vectors in vacuum. The same happens with the magnetic field ($\bf{H}$) and the magnetic flux density ($\bf{B}$) vectors (up to the constant $\mu_0^{-1}$). The fact that gravity may change this by effectively inducing dielectric or magnetic responses to the primary fields is commonly overlooked. It is the purpose of this communication to call attention to classical polarization or magnetization of the vacuum due to the concomitant presence of gravitational and electromagnetic sources. The formalism of differential forms (exterior calculus) is used since it provides a clear-cut way to achieve this. This work offers new routes for possible detection of various spacetime geometries via their electromagnetic manifestations and the way they influence light propagation.