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arXiv · 1502.02993

Non-perturbative Calculation of the Positronium Mass Spectrum in Basis Light-Front Quantization

Paul Wiecki·Yang Li·Xingbo Zhao·Pieter Maris·James P. Vary
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Abstract

We report on recent improvements to our non-perturbative calculation of the positronium spectrum. Our Hamiltonian is a two-body effective interaction which incorporates one-photon exchange terms, but neglects fermion self-energy effects. This effective Hamiltonian is diagonalized numerically in a harmonic oscillator basis at strong coupling ($\alpha=0.3$) to obtain the mass eigenvalues. We find that the mass spectrum compares favorably to the Bohr spectrum of non-relativistic quantum mechanics evaluated at this unphysical coupling.

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Paul Wiecki, Yang Li, Xingbo Zhao, Pieter Maris, James P. Vary. 2015-02-10. Non-perturbative Calculation of the Positronium Mass Spectrum in Basis Light-Front Quantization. https://doi.org/10.1007/s00601-015-0962-3

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