Global sampling of Feynman's diagrams through normalizing flow

Autor(en)

Luca Leoni, Cesare Franchini

Abstrakt

Normalizing flows (NF) are powerful generative models with increasing applications in augmenting Monte Carlo algorithms due to their high flexibility and expressiveness. In this work we explore the integration of NF in the diagrammatic Monte Carlo (DMC) method, presenting an architecture designed to sample the intricate multidimensional space of Feynman's diagrams through dimensionality reduction. By decoupling the sampling of diagram order and interaction times, the flow focuses on one interaction at a time. This enables one to construct a general diagram by employing the same unsupervised model iteratively, dressing a zero-order diagram with interactions determined by the previously sampled order. The resulting NF-augmented DMC method is tested on the widely used single-site Holstein polaron model in the entire electron-phonon coupling regime. The obtained data show that the model accurately reproduces the diagram distribution by reducing sample correlation and observables' statistical error, constituting the first example of global sampling strategy for connected Feynman's diagrams in the DMC method.

Organisation(en)

Computergestützte Materialphysik

Externe Organisation(en)

Università di Bologna

Journal

Physical Review Research

Band

6

Anzahl der Seiten

8

ISSN

2643-1564

DOI

https://doi.org/10.48550/arXiv.2402.00736

Publikationsdatum

07-2024

Peer-reviewed

Ja

ÖFOS 2012

103015 Kondensierte Materie, 102019 Machine Learning, 103043 Computational Physics

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/034957c4-bb5c-4979-8b5b-febdbb69957c