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On a motion equation for two particles in relativistic quantum mechanics

Wilhelm I. Fushchych
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Abstract

The purpose of the present note is to propose, in the framework of relativistic quantum mechanics, a new Poincare-invariant equation for two particles with masses m_1, m_2 and spin s_1=s_2=1/2. It is a first-order linear differential equation for the eight-component wave function. With the help of this equation the description of the motion of two-particle systems is reduced to the description of one-particle systems in the (1+6)-dimensional Minkowski space which can be in two spin states (s=0 or s=1).

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Wilhelm I. Fushchych. 2002-06-21. On a motion equation for two particles in relativistic quantum mechanics. https://arxiv.org/abs/quant-ph/0206154

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