Novel duality-invariant theories of electrodynamics
Abstract
We identify new families of duality-invariant theories of electrodynamics. We achieve this in two different ways. On the one hand, we present an algorithm to construct a one-parameter family of exactly duality-invariant theories from a single seed duality-invariant theory. If the seed theory is causal, the theories constructed from this method will also be causal when the parameter is non-negative. On the other hand, we find two additional novel families of duality-invariant theories which include a nonzero term independent of the electromagnetic field. The first of them generalizes Bialynicki-Birula electrodynamics, while the second family of theories features a well-defined Maxwell limit as the term independent of the gauge field strength is sent to zero.
Keywords
Cite
@article{arxiv.2507.16502,
title = {Novel duality-invariant theories of electrodynamics},
author = {Ángel J. Murcia},
journal= {arXiv preprint arXiv:2507.16502},
year = {2025}
}
Comments
5 pages + appendices. Some citations added. New section in appendix added. Matches published version