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arXiv · 0705.0133

Effective Lagrangian at Cubic Order in Electromagnetic Fields and Vacuum Birefringence

S. I. Kruglov
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Abstract

The effective Lagrangian of electromagnetic fields at the cubic order in field strength has been considered. This generalized Lagrangian is motivated by electrodynamics on non-commutative spaces. We find the canonical and symmetrical energy-momentum tensors and show that they possess non-zero traces. The propagation of a linearly polarized laser beam in the external transverse magnetic field is investigated. We evaluate the induced ellipticity which allows us to obtain a constraint on parameters introduced from the PVLAS experimental data.

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S. I. Kruglov. 2007-08-09. Effective Lagrangian at Cubic Order in Electromagnetic Fields and Vacuum Birefringence. https://doi.org/10.1016/j.physletb.2007.06.069

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