Starting week 45 (02.11.2026) – every Thursday from 10am - 12pm in room B1 – ending week 51, (18.12.2026)
Description of the course:
This graduate-level course provides an introduction to nonperturbative phenomena in quantum field theory
(QFT), with a particular focus on instantons and renormalons. We will develop semiclassical methods for
studying nonperturbative effects, emphasizing the role of topology and the structure of the quantum vacuum.
The course will also cover the relation between instantons and quantum anomalies, as well as their relevance for
spontaneous symmetry breaking in gauge theories. Finally, we will introduce renormalons and explore their
connection with the large-order behavior of perturbation theory and nonperturbative power corrections. Several
applications to strongly coupled theories will be discussed, with quantum chromodynamics (QCD) serving as the
main case study.
Learning results of the course:
The course is aimed at Ph.D. students and early-stage researchers interested in nonperturbative aspects of QFT
that are typically beyond the scope of standard courses. By the end of the course, students will have acquired
an understanding of the main nonperturbative effects, including instantons, solitons, and renormalons.
Additionally, they will become familiar with semiclassical methods and their applications to realistic quantum
field theories.
Lecturer:
Dr. Jahmall Bersini
