Probing resonant spectra using functional integrals (Nils WAGNER, Technische Universität München)

13.02.2026 14:00

In the study of quantum-mechanical tunneling processes, numerous approaches have been developed to determine the decay rate of states initially confined within a metastable potential region. Virtually all analytical treatments, however, fall into one of two superficially unrelated conceptual frameworks: the resonant-state approach and the instanton method. Whereas the concept of resonant states and their associated decay widths is grounded in physical reasoning by capturing the regime of uniform probability decay, the instanton method lacks such a clear physical interpretation. In this talk, I will show that these two seemingly distinct approaches are directly connected, a link that emerges from constructing functional integrals associated to generalized eigenvalue problems with sectorial boundary conditions in the complex plane. Beyond describing decay processes, the resulting formulation offers a versatile tool for investigating the spectra of generalized eigenvalue problems, including those encountered in PT-symmetric quantum mechanics.

Lieu

Conseil Général 7-9, Room 8-02, Séminaire Physique Mathématique

entrée libre