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arXiv · hep-ph/0610426

Improved superposition schemes for approximate multi-caloron configurations

Abstract

Two improved superposition schemes for the construction of approximate multi-caloron-anticaloron configurations, using exact single (anti)caloron gauge fields as underlying building blocks, are introduced in this paper. The first improvement deals with possible monopole-Dirac string interactions between different calorons with non-trivial holonomy. The second one, based on the ADHM formalism, improves the (anti-)selfduality in the case of small caloron separations. It conforms with Shuryak's well-known ratio-ansatz when applied to instantons. Both superposition techniques provide a higher degree of (anti-)selfduality than the widely used sum-ansatz, which simply adds the (anti)caloron vector potentials in an appropriate gauge. Furthermore, the improved configurations (when discretized onto a lattice) are characterized by a higher stability when they are exposed to lattice cooling techniques.

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Philipp Gerhold, Ernst-Michael Ilgenfritz, Michael Müller-Preussker. 2007-04-16. Improved superposition schemes for approximate multi-caloron configurations. https://doi.org/10.1016/j.nuclphysb.2007.04.003

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