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arXiv · 1405.3928

The positronium in a mean-field approximation of quantum electrodynamics

Jérémy Sok
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Abstract

The Bogoliubov-Dirac-Fock (BDF) model is a no-photon, mean-field approxi- mation of quantum electrodynamics. It describes relativistic electrons in the Dirac sea. In this model, a state is fully characterized by its one-body density matrix, an infinite rank nonnegative operator. We prove the existence of the positronium, the bound state of an electron and a positron, represented by a critical point of the energy functional in the absence of external field. This state is interpreted as the ortho-positronium, where the two particles have parallel spins.

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Jérémy Sok. 2014-05-15. The positronium in a mean-field approximation of quantum electrodynamics. https://arxiv.org/abs/1405.3928

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