Analytic continuation and physical content of the gluon propagator
Abstract
The analytic continuation of the gluon propagator is revised in the light of recent findings on the possible existence of complex conjugated poles. The contribution of the anomalous pole must be added when Wick rotating, leading to an effective Minkowskian propagator which is not given by the trivial analytic continuation of the Euclidean function. The effective propagator has an integral representation in terms of a spectral function which is naturally related to a set of elementary (complex) eigenvalues of the Hamiltonian, thus generalizing the usual K\"allen-Lehmann description. A simple toy model shows how the elementary eigenvalues might be related to actual physical quasiparticles of the non-perturbative vacuum.
Keywords
Cite
@article{arxiv.2210.11541,
title = {Analytic continuation and physical content of the gluon propagator},
author = {Fabio Siringo and Giorgio Comitini},
journal= {arXiv preprint arXiv:2210.11541},
year = {2023}
}
Comments
Editorially accepted version, with an entirely new introduction, a figure on Wick rotation and many more references