The connection between electromagnetic stress tensors and the dielectric constant in a medium
Classical Physics
2026-01-14 v1
Abstract
We perform explicit calculations for microscopic models to confirm that a single, unique electromagnetic stress tensor exists in a dielectric medium: the microscopic tensor \sigma^{#}. We demonstrate that the conventional macroscopic stress tensor of continuum electrodynamics, which contains the derivative of the dielectric coefficient, is merely a representation of \sigma^{#}'s spatial average. This result establishes that, contrary to claims in the literature, both this averaged electromagnetic stress and the hydrodynamic pressure always possess a unique physical meaning.
Keywords
Cite
@article{arxiv.2601.08635,
title = {The connection between electromagnetic stress tensors and the dielectric constant in a medium},
author = {R. Dengler},
journal= {arXiv preprint arXiv:2601.08635},
year = {2026}
}