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On the possible types of equations for zero-mass particles

Wilhelm I. Fushchych·Anatoly G. Nikitin
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Abstract

There are a number of papers dedicated to the description of free particles and antiparticles with zero mass and spin 1/2. A great many equations with different C, P, T properties have been proposed and the impression could be formed that there are many nonequivalent theories for zero-mass particles. The purpose or this paper is to show that it is not the case and to describe all nonequivalent equations.

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Wilhelm I. Fushchych, Anatoly G. Nikitin. 2002-06-17. On the possible types of equations for zero-mass particles. https://arxiv.org/abs/quant-ph/0206109

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