Speaker
Description
The resolution of strongly correlated systems is a computationally challenging task, which can be simplified enormously by choosing a formulation in terms of the appropriate degrees of freedom. Here, we distinguish between transformations of the fundamental degrees of freedom in the path integral, and transformations of mean fields.
Both are incorporated naturally in the renormalisation group approach and appear as dynamic, infinitesimal changes of the field representation with changing scales. A historically very prominent use case is dynamic rebosonisation, which implements the Hubbard-Stratonovich transformation throughout the RG flow, but recent investigations are studying a wider field of applications.
In my talk I will discuss the point of view of the physics-informed RG (PIRG) [1,2], which considers both the flow of a generating functional and the flow of the field on equal footing. This pair must fulfill a generalised flow equation and an additional constraint equation that can be chosen to suit a specific purpose.
Firstly, I we consider the PIRG for microscopic field-transformations [3]. Here, they bridge the gap to generative sampling architectures in lattice field theory. Specifically, the optimal transport nature of the RG allows to address long standing problems such as the sign-problem in real-time lattice simulations [4].
Secondly, I consider generalised flows of the effective action. Here the PIRG perspective allows to formulate novel optimisation procedures for expansion schemes [5,6], or the restoration of gauge symmetries which are explicitly broken by the RG flow [7,8].
[1] FI, J. M. Pawlowski, Annals Phys. 481 (2025) 170177
[2] FI, J. M. Pawlowski, Phys.Rev.D 113 (2026) 7, 076003
[3] FI, R. Kapust, J. M. Pawlowski, arXiv:2510.26678
[4] FI, R. Kapust, J. M. Pawlowski, arXiv:2603.03159
[5] FI, J. M. Pawlowski, arXiv:2305.00816
[6] A. Bonanno, FI, J. M. Pawlowski, SciPost Phys.Core 9 (2026) 005
[7] FI, J. M. Pawlowski, Phys.Rev.D 112 (2025) 10, 105005
[8] FI, B. Knorr, S. Mezger, J. M. Pawlowski, P. Sprenger, In preparation
| Affiliation | Ruhr-Universität Bochum |
|---|---|
| Career status | Postdoc |