2008/10/31 by Gert Aarts · 6 citations
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #High-Energy Particle Collisions Research #Quantum Chromodynamics and Particle Interactions #cond-mat.other #hep-lat #hep-ph #nucl-th
paper · pdf · doi:10.1103/physrevlett.102.131601
published as Phys.Rev.Lett.102:131601,2009 · 4 pages, 4 eps figures, v2: minor changes, outlook expanded, references added, to appear in PRL
arxiv created 2009/03/12 · openalex publication_date 2009/04/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A nonperturbative study of field theories with a complex action, such as QCD at finite baryon density, is difficult due to the sign problem. We show that the relativistic Bose gas at finite chemical potential has a sign and "silver blaze" problem, similar to QCD. We then apply stochastic quantization and complex Langevin dynamics to study this theory with nonperturbative lattice simulations. Independence of chemical potential at small and a transition to a condensed phase at large chemical potential are found. Lattices of size N4, with N=4, 6, 8, 10, are used. We show that the sign problem is severe, however, we find that it has no negative effect using this approach. This improves the prospects of applying stochastic quantization to QCD at nonzero density.