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Bound states in Yukawa theory

Axel Weber·Norbert E. Ligterink
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Abstract

A generalization of the Gell-Mann-Low Theorem is applied to bound state calculations in Yukawa theory. The resulting effective Schroedinger equation is solved numerically for two-fermion bound states with the exchange of a massless boson. The complete low-lying bound state spectrum is obtained for different ratios of the constituent masses. No abnormal solutions are found. We show the consistency of the non-relativistic and one-body limits and discuss the special cases of identical fermions and fermion-antifermion states. To our knowledge, this is the first consistent calculation of bound states in pure Yukawa theory (without UV cutoff).

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Axel Weber, Norbert E. Ligterink. 2005-06-13. Bound states in Yukawa theory. https://doi.org/10.1007/s00601-009-0056-1

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