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Exact two-particle eigenstates in partially reduced QED

Jurij W. Darewych·Askold Duviryak
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Abstract

We consider a reformulation of QED in which covariant Green functions are used to solve for the electromagnetic field in terms of the fermion fields. It is shown that exact few-fermion eigenstates of the resulting Hamiltonian can be obtained in the canonical equal-time formalism for the case where there are no free photons. These eigenstates lead to two- and three-body Dirac-like equations with electromagnetic interactions. Perturbative and some numerical solutions of the two-body equations are presented for positronium and muonium-like systems, for various strengths of the coupling.

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Jurij W. Darewych, Askold Duviryak. 2010-11-18. Exact two-particle eigenstates in partially reduced QED. https://doi.org/10.1103/physreva.66.032102

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