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arXiv · 2311.04278

Hamiltonian birefringence and Born-Infeld limits

Luca Mezincescu·Jorge G. Russo·Paul K. Townsend
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Abstract

Using Hamiltonian methods, we find six relativistic theories of nonlinear electrodynamics for which plane wave perturbations about a constant uniform background are not birefringent. All have the same conformal strong-field limit to Bialynicki-Birula (BB) electrodynamics, but only four avoid superluminal propagation: Born-Infeld (BI), its non-conformal ``extreme'' limits (electric and magnetic) and the conformal BB limit. The quadratic dispersion relation of BI is shown to degenerate in the extreme limits to a pair of linear relations, which become identical in the BB limit.

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Luca Mezincescu, Jorge G. Russo, Paul K. Townsend. 2023-11-07. Hamiltonian birefringence and Born-Infeld limits. https://arxiv.org/abs/2311.04278

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