The Feynman chessboard model in 3+1 dimensions

The chessboard model was Feynman's adaptation of his path integral method to a two-dimensional relativistic domain. It is shown that chessboard paths encode information about the contiguous pairs of paths in a spacetime plane, as required by discrete worldlines in Minkowski space. The application of coding by pairs in a four-dimensional spacetime is then restricted by the requirements of the Lorentz transformation, and the implementation of these restrictions provides an extension of the model to 4D, illuminating the relationship between relativity and quantum propagation.

Automated summary

The chessboard model is Feynman's adaptation of his path integral method to a two-dimensional relativistic domain. It encodes information about contiguous path pairs in a spacetime plane, as required by discrete worldlines in Minkowski space. The extension of this model to 4D is restricted by the requirements of Lorentz transformation, but it provides an illumination of the relationship between relativity and quantum propagation.