2021/11/02 by Erhard Seiler, Seiler, Erhard
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #Protein Structure and Dynamics #Quantum many-body systems #Theoretical and Computational Physics #hep-lat
paper · pdf · doi:10.48550/arxiv.2111.01609
7 pages, 2 figures. Contribution to Lattice 21
arxiv created 2021/11/02 · openalex publication_date 2021/11/02 · arxiv updated 2021/11/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The complex Langevin method is a general method to treat systems with complex action, such as QCD at nonzero density. The formal justification relies on the absence of certain boundary terms, both at infinity and at the unavoidable poles of the drift force. Here I focus on the boundary terms at these poles for simple models, which so far have not been discussed in detail. The main result is that those boundary terms (for the "un-evolved" observables) arise after running the Langevin process for a finite time and vanish again as the Langevin time goes to infinity. This is in contrast to the boundary terms at infinity, which can be found to occur in the long time limit (cf. the contribution by Dénes Sexty).