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Revealing Topological Structure in the SU(2) Vacuum

Thomas DeGrand·Anna Hasenfratz·Tamas G. Kovacs
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Abstract

In this paper we derive a simple parametrization of the cycling method developed by us in our earlier work. The new method, called renormalization group (RG) mapping, consists of a series of carefully tuned APE-smearing steps. We study the relation between cycling and RG mapping. We also investigate in detail how smooth instantons and instanton-anti-instanton pairs behave under the RG mapping transformation. We use the RG mapping technique to study the topological susceptibility and instanton size distribution of SU(2) gauge theory. We find scaling in both quantities in a wide range of coupling values. Our result for the topological susceptibility, chi^1/4=220(6) MeV, agrees with our earlier results.

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Thomas DeGrand, Anna Hasenfratz, Tamas G. Kovacs. 1997-11-17. Revealing Topological Structure in the SU(2) Vacuum. https://doi.org/10.1016/s0550-3213(98)00181-3

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