Front form QED(3+1): The spin-multiplet structure of the positronium spectrum at strong coupling

TL;DR

This paper investigates the positronium spectrum in the front form of QED at strong coupling, focusing on deriving an effective interaction and its rotational invariance, with numerical results supporting the analysis.

Contribution

It provides numerical analysis of the positronium spectrum in strong coupling QED and examines the rotational invariance of the effective interaction in the front form.

Findings

Numerical results on the positronium spectrum at large coupling.

Analysis of the rotational invariance of the effective interaction.

Insights into deriving effective interactions in strong coupling regimes.

Abstract

Numerical results on the positronium spectrum in the front form of QED at large coupling constant are presented. Emphasis is put on the question whether one can derive an effective interaction at all, and whether this effective interaction is rotationally invariant. (Proceedings of Les Houches 1997)