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arXiv · 1203.3122

Relativistic Lagrangian model of a nematic liquid crystal interacting with an electromagnetic field

Yuri N. Obukhov·Tomas Ramos·Guillermo F. Rubilar
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Abstract

We develop a relativistic variational model for a nematic liquid crystal interacting with an electro- magnetic field. The constitutive relation for a general anisotropic uniaxial diamagnetic and dielectric medium is analyzed. We discuss light wave propagation in this moving uniaxial medium, for which the corresponding optical metrics are identified explicitly. A Lagrangian for the coupled system of a nematic liquid crystal and the electromagnetic field is constructed, from which a complete set of equations of motion for the system is derived. The canonical energy-momentum and spin tensors are systematically obtained. We compare our results with those within the non-relativistic models. As an application of our general formalism, we discuss the so-called Abraham-Minkowski controversy on the momentum of light in a medium.

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Yuri N. Obukhov, Tomas Ramos, Guillermo F. Rubilar. 2012-09-13. Relativistic Lagrangian model of a nematic liquid crystal interacting with an electromagnetic field. https://doi.org/10.1103/physreve.86.031703

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