Polyakov's spin factor and new algorithms for efficient perturbative computations in QCD

TL;DR

This paper explores Polyakov's spin factor within the path-integral framework of QCD, leading to new algorithms that simplify perturbative calculations by separating spin effects from interaction dynamics.

Contribution

It introduces novel algorithms for perturbative QCD computations by leveraging the separation of spin factors and interaction dynamics via Wilson lines.

Findings

Development of master expressions for perturbative series

Enhanced computational efficiency in QCD calculations

New insights into spin and interaction separation

Abstract

Polyakov's spin factor enters as a weight in the path-integral description of particle-like modes propagating in Euclidean space-times, accounting for particle spin. The Fock-Feynman-Schwinger path integral applied to QCD accomodates Polyakov's spin factor in a natural manner while, at the same time, it identifies Wilson line (loop) operators as sole agents of interaction dynamics among matter and gauge field quanta. A direct application of such a separation between spin content and dynamics is the emergence of master expressions for the perturbative series involving either open or closed fermionic lines which provide new, comprehensive approaches to perturbative QCD.