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arXiv · 0906.1432

Causal Propagation of a Charged Spin 3/2 Field in an External Electromagnetic Background

Massimo Porrati·Rakibur Rahman
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Abstract

We present a Lagrangian for a massive, charged spin 3/2 field in a constant external electromagnetic background, which correctly propagates only physical degrees of freedom inside the light cone. The Velo-Zwanziger acausality and other pathologies such as loss of hyperbolicity or the appearance of unphysical degrees of freedom are avoided by a judicious choice of non-minimal couplings. No additional fields or equations besides the spin 3/2 ones are needed to solve the problem.

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Massimo Porrati, Rakibur Rahman. 2009-07-07. Causal Propagation of a Charged Spin 3/2 Field in an External Electromagnetic Background. https://doi.org/10.1103/physrevd.80.025009

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