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arXiv · 1404.6234

Basis Light-Front Quantization Approach to Positronium

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

We present the first application of the recently developed Basis Light-Front Quantization (BLFQ) method to self-bound systems in quantum field theory, using the positronium system as a test case. Within the BLFQ framework, we develop a two-body effective interaction, operating only in the lowest Fock sector, that implements photon exchange, neglecting fermion self-energy effects. We then solve for the mass spectrum of this interaction at the unphysical coupling $α=0.3$. The resulting spectrum is in good agreement with the expected Bohr spectrum of non-relativistic quantum mechanics. We examine in detail the dependence of the results on the regulators of the theory.

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Paul Wiecki, Yang Li, Xingbo Zhao, Pieter Maris, James P. Vary. 2015-06-25. Basis Light-Front Quantization Approach to Positronium. https://doi.org/10.1103/physrevd.91.105009

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