Yang-Mills at Strong vs. Weak Coupling: Renormalons, OPE And All That

TL;DR

This paper explores the limitations of perturbative expansions in Yang-Mills theories with asymptotic freedom, focusing on the roles of renormalons and the operator product expansion (OPE).

Contribution

It analyzes the applicability of perturbative methods in different regimes of Yang-Mills theories, highlighting the impact of strong and weak coupling.

Findings

Perturbative expansions have limited validity at strong coupling.

Renormalons influence the divergence of perturbative series.

OPE provides insights into non-perturbative effects.

Abstract

I discuss various situations in which perturbative expansions are used in Yang-Mills theories with asymptotic freedom and establish the limits of its applicability.