2002/01/21 by Pedro Bicudo, P. J. A. Bicudo, A. V. Nefediev +1 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.65.085026
published as Phys.Rev. D65 (2002) 085026 · RevTeX4, 26 pages, 8 EPS figures, extended references, corrected some typos, to appear in Phys.Rev.D
arxiv created 2002/01/21 · openalex publication_date 2002/04/08 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The properties of the vacuum are addressed in two- and four-dimensional quark models for QCD. It is demonstrated that two-dimensional QCD (the 't Hooft model) possesses only one possible vacuum state---the solution to the mass-gap equation, which provides spontaneous breaking of chiral symmetry (SBCS). On the contrary, the four-dimensional theory with confinement modeled by the linear potential with a Coulomb OGE interaction not only has a chirally noninvariant ground vacuum state, but possesses an excited vacuum replica, which also exhibits SBCS and can be realized as a metastable intermediate state of hadronic systems. We discuss the influence of this vacuum replica on physical observables as well as on the possibility of probing the vacuum background fields in QCD.