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arXiv · 2507.16502

Novel duality-invariant theories of electrodynamics

Ángel J. Murcia
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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.

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Ángel J. Murcia. 2025-07-22. Novel duality-invariant theories of electrodynamics. https://arxiv.org/abs/2507.16502

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