Renormalons, integrable QFTs and resurgence

Thursday 1 Feb 2024, 14:00 → 15:00 Europe/Berlin

HS3 (Physikdepartment)

Understanding the behavior of perturbative series in quantum field theory (QFT) is an old and venerable problem. In the 1970s-1980s it was found that this behavior is closely connected to non-perturbative physics, and ’t Hooft and Parisi argued that the most important non-perturbative corrections in asymptotically free theories are due to so-called renormalons. In this talk I will first summarize what is known about the physics and mathematics of renormalons. I will then argue that integrable, asymptotically free theories in two dimensions provide an excellent laboratory to obtain analytic results on the structure or renormalons. Some of these results provide information on renormalons beyond the large N limit, and turn out to challenge the standard orthodoxy on the subject. They also provide concrete realizations of the ideas of resurgence in QFT.