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arXiv · 2506.20784

Lorentz invariant materials and metamaterials

Jon Lasa-Alonso·Gabriel Molina-Terriza
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Abstract

We show that electromagnetic constitutive relations of materials, defined by a scalar permittivity, $\varepsilon$, and permeability, $\mu$, are the same for all inertial observers provided that $\varepsilon\mu = 1$ is satisfied. To highlight the practical power of our general result, we discuss schemes in which this property plays a significant role, such as Fresnel-Fizeau optical drag or modified Snell's law for moving dielectrics. We also proof that such a particular behavior can be extended to systems like uniaxial anisotropic media or negative refractive index metamaterials.

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Jon Lasa-Alonso, Gabriel Molina-Terriza. 2025-06-25. Lorentz invariant materials and metamaterials. https://arxiv.org/abs/2506.20784

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