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arXiv · hep-ph/0701013

A spinorial perspective on massless photons

Giampiero Esposito
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Abstract

We exploit the fact that, in Minkowski space-time, gamma matrices are possibly more fundamental than the metric to describe how gauge invariance at perturbative level enforces a Lagrangian for spinor electrodynamics with massless photons. The term quadratic in the potential arises naturally in the gauge-fixed Lagrangian but has vanishing coefficient.

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Giampiero Esposito. 2007-01-02. A spinorial perspective on massless photons. https://doi.org/10.1007/s10701-007-9191-z

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