Calculating propagators for relativistic wave equations

Mingjie Li; S. A. R. Horsley

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arXiv · 2504.06329

Calculating propagators for relativistic wave equations

Mingjie Li·S. A. R. Horsley

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Abstract

Here we examine the propagation of relativistic fields in spacetime using the viewpoint applied to derive the Rayleigh--Sommerfeld diffraction integral in three--dimensional space. We use this theory to find the propagators for both the Klein--Gordon equation and the Dirac equation. Based on these results, we highlight some apparently overlooked aspects of the Feynman checkerboard model as it is usually applied to the Dirac equation.

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Mingjie Li, S. A. R. Horsley. 2025-04-08. Calculating propagators for relativistic wave equations. https://arxiv.org/abs/2504.06329

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