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Riemannian light cone from vanishing birefringence in premetric vacuum electrodynamics

Claus Lämmerzahl·Friedrich W. Hehl
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Abstract

We consider premetric electrodynamics with a local and linear constitutive law for the vacuum. Within this framework, we find quartic Fresnel wave surfaces for the propagation of light. If we require vanishing birefringence in vacuum, then a Riemannian light cone is implied. No proper Finslerian structure can occur. This is generalized to dynamical equations of any order.

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Claus Lämmerzahl, Friedrich W. Hehl. 2004-11-22. Riemannian light cone from vanishing birefringence in premetric vacuum electrodynamics. https://doi.org/10.1103/physrevd.70.105022

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