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arXiv · 2108.01103

Democratic Lagrangians for Nonlinear Electrodynamics

Zhirayr Avetisyan·Oleg Evnin·Karapet Mkrtchyan
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Abstract

We construct a Lagrangian for general nonlinear electrodynamics that features electric and magnetic potentials on equal footing. In the language of this Lagrangian, discrete and continuous electric-magnetic duality symmetries can be straightforwardly imposed, leading to a simple formulation for theories with the $SO(2)$ duality invariance. When specialized to the conformally invariant case, our construction provides a manifestly duality-symmetric formulation of the recently discovered ModMax theory. We briefly comment on a natural generalization of this approach to $p$-forms in $2p+2$ dimensions.

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Zhirayr Avetisyan, Oleg Evnin, Karapet Mkrtchyan. 2021-11-10. Democratic Lagrangians for Nonlinear Electrodynamics. https://doi.org/10.1103/physrevlett.127.271601

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