The quantum effective potential in fermionic theories from constrained path integrals

by Laurin Pannullo (Bielefeld)

Thursday 6 Jun 2024, 14:15 → 15:30 Europe/Berlin

Abbeanum/Ground floor-HS 2 - Hörsaal 2 (TPI, FSU Jena)

I will discuss methods to constrain fermionic condensates on the level of the path integral, which grants access to the quantum effective potential in the infinite volume limit. In the case of a spontaneously broken symmetry, this potential possesses a manifestly flat region, which is inaccessible to the standard approach on the lattice. However, by constraining the appropriate order parameters such as the chiral condensate, one is then able to probe the flat region and determine the value of the order parameter precisely. Lattice QCD simulations investigating the breaking of chiral symmetry could immensely benefit from this technique.  I demonstrate one method of constraining fermionic condensates in the 2-dimensional (chiral) Gross-Neveu model, which exhibits a spontaneously broken chiral symmetry and discuss the structure of dominant configurations within the flat region.