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arXiv · hep-ph/0201173

Vacuum replicas in QCD

P. J. A. Bicudo·A. V. Nefediev·J. E. F. T. Ribeiro
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Abstract

The properties of the vacuum are addressed in the two- and four-dimensional quark models for QCD. It is demonstrated that the two-dimensional QCD ('t Hooft model) possesses only one possible vacuum state - the solution to the mass-gap equation, which provides spontaneous breaking of the chiral symmetry (SBCS). On the contrary, the four-dimensional theory with confinement modeled by the linear potential supplied by the Coulomb OGE interaction, not only has the chirally-noninvariant ground vacuum state, but it possesses an excited vacuum replica, which also exhibits SBCS and can realize as a metastable intermediate state of hadronic systems. We discuss the influence of the latter on physical observables as well as on the possibility to probe the vacuum background fields in QCD.

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P. J. A. Bicudo, A. V. Nefediev, J. E. F. T. Ribeiro. 2002-01-21. Vacuum replicas in QCD. https://doi.org/10.1103/physrevd.65.085026

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