Complex Langevin dynamics and zeroes of the fermion determinant

• Verfasst von: Aarts, Gert [VerfasserIn]
• Verfasst von: Stamatescu, Ion-Olimpiu [VerfasserIn]
• Verfasst von: Sexty, Dénes [VerfasserIn]
• Titel: Complex Langevin dynamics and zeroes of the fermion determinant
• Verf.angabe: Gert Aarts, Erhard Seiler, Dénes Sexty and Ion-Olimpiu Stamatescu
• E-Jahr: 2017
• Jahr: May 9, 2017
• Umfang: 62 S.
• Teil: year:2017
• Teil: number:20
• Teil: extent:62
• Fussnoten: Gesehen am 20.09.2018
• Titel Quelle: Enthalten in: Journal of high energy physics
• Ort Quelle: Berlin : Springer, 1997
• Jahr Quelle: 2017
• Band/Heft Quelle: (2017,20) Artikel-Nummer 44, 62 Seiten
• ISSN Quelle: 1029-8479
• DOI: doi:10.1007/JHEP05(2017)044
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Lattice Quantum Field Theory
• Sach-SW: Phase Diagram of QCD
• K10plus-PPN: 1581135637

Abstract

QCD at nonzero baryon chemical potential suffers from the sign problem, due to the complex quark determinant. Complex Langevin dynamics can provide a solution, provided certain conditions are met. One of these conditions, holomorphicity of the Langevin drift, is absent in QCD since zeroes of the determinant result in a meromorphic drift. We first derive how poles in the drift affect the formal justification of the approach and then explore the various possibilities in simple models. The lessons from these are subsequently applied to both heavy dense QCD and full QCD, and we find that the results obtained show a consistent picture. We conclude that with careful monitoring, the method can be justified a posteriori, even in the presence of meromorphicity.