Probing the Boundary of the Non-Perturbative QCD by Small Size Instantons

E. V. Shuryak

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arXiv · hep-ph/9909458

Probing the Boundary of the Non-Perturbative QCD by Small Size Instantons

E. V. Shuryak

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Abstract

The lattice data on the instanton size distribution suggest an additional O($ρ^2)$ action. The small-$ρ$ effect O($ρ^4)$ predicted by the Operator Product Expansion (OPE) is not observed. Similar deviations are also found for non-perturbative response to a small static color dipoles: it is O(r) not O(r$^2$). We suggest that small instanton radii in the QCD vacuum and small radii of the QCD strings (to which this observation relates) are consequences of the same phenomenon: a very robust dual superconductivity in the QCD vacuum, with relatively large Higgs VEV and surprisingly large Higgs mass.

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E. V. Shuryak. 1999-09-21. Probing the Boundary of the Non-Perturbative QCD by Small Size Instantons. https://arxiv.org/abs/hep-ph/9909458

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