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Some exact solutions of reduced scalar Yukawa theory

Jurij W. Darewych
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Abstract

The scalar Yukawa model, in which a complex scalar field interact via a real scalar field, is reduced by using covariant Green functions. It is shown that exact few-particle eigenstates of the truncated QFT Hamiltonian can be obtained in the Feshbach-Villars formulation if an unorthodox "empty" vacuum state is used. Analytic solutions for the two-body case are obtained for massless chion exchange in 3+1 dimensions and for massive chion exchange in 1+1 dimensions. Comparison is made to ladder Bethe-Salpeter, Feynman-Schwinger and quasipotential results for massive chion exchange in 3+1. Equations for the three-body case are also obtained.

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Jurij W. Darewych. 1998-07-02. Some exact solutions of reduced scalar Yukawa theory. https://doi.org/10.1139/cjp-76-7-523

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