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arXiv · hep-lat/9804027

Instantons and Monopoles in the Nonperturbative QCD

Hideo Suganuma·Hiroko Ichie·Atsunori Tanaka·Kazuhisa Amemiya
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Abstract

We study the confinement physics in QCD in the maximally abelian (MA) gauge using the SU(2) lattice QCD. To clarify the origin of abelian dominance for the long-range physics, we study the charged-gluon propagator in the lattice QCD, and find that the effective mass $m_{ch} \simeq 0.9 {\rm GeV}$ of the charged gluon is induced by the MA gauge fixing. In the MA gauge, there appears the global network of the monopole world-line covering the whole system, which would be identified as monopole condensation at a large scale. To prove monopole condensation, we apply the dual gauge formalism to the monopole part, and derive the inter-monopole potential from the dual Wilson loop in the MA gauge. In the monopole part, which carries the nonperturbative aspects of QCD, the dual gluon mass is evaluated as $m_B \simeq $0.5GeV, which is the evidence of the dual Higgs mechanism by monopole condensation. As for the monopole structure, the large fluctuation of off-diagonal gluons remains around the monopole in the MA gauge, and large cancellation occurs between the diagonal and off-diagonal action densities to keep the total QCD action finite. The charged-gluon rich region around the QCD-monopole would provide the effective monopole size as the critical scale of the abelian projected QCD. Instantons are expected to appear in the charged-gluon rich region around the monopole world-line in the MA gauge, which leads to the local correlation between monopoles and instantons.

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BibTeXRIS

Hideo Suganuma, Hiroko Ichie, Atsunori Tanaka, Kazuhisa Amemiya. 1998-05-13. Instantons and Monopoles in the Nonperturbative QCD. https://doi.org/10.1143/ptps.131.559

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