During the past decades, the functional renormalization group (fRG) has been established as a powerful tool for the computation of correlation functions in quantum many-body systems. In particular, it is widely used to tackle the many-electron problem or the field of quantum magnetism. Through the recent multi-loop extension, it has become a quantitative method, producing fully self-consistent solutions up to the two-particle level.

Even though the structure of the flow equations to be solved allows massive parallelization, their numerical solution is a very demanding task. This is mainly due to the sheer complexity of the functions involved, particularly the four-point vertex. The setup of an fRG code thus requires a lot of numerical know-how and experience in software development.

Many of these numerical challenges in the fRG context are very similar, regardless of the concrete physical application in mind. Nevertheless, over the years, many groups have developed their very own fRG codes, often without collaboration with others. This means that many technical struggles are solved independently many times by different people.

This workshop addresses that issue by bringing together the actual practitioners of the fRG method in condensed matter physics, namely the Ph.D. students and Post-Docs working on the numerical codes.

The participants will learn about the work and struggles of other groups from presentations about the different codes that already exist and the physical problems they are meant to address. Open discussion rounds shall enable brainstorming about possible solutions to ubiquitous numerical challenges in the fRG context and a poster session will allow more detailed and personal conversations.