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On the three types of relativistic equations for particles with nonzero mass

Wilhelm I. Fushchych
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Abstract

In previous papers quant-ph/0206077, quant-ph/0206078, quant-ph/0206079 we have shown that there exist three types of the relativistic equations for the massless particles. Here we show that for the free particles and antiparticles with the mass m>0 and the arbitrary spin $s \geq 1/2$ there also exist three types of nonequivalent equations.

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Wilhelm I. Fushchych. 2002-06-17. On the three types of relativistic equations for particles with nonzero mass. https://arxiv.org/abs/quant-ph/0206104

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