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Abelian Projection without Ambiguities

A. J. van der Sijs
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Abstract

Laplacian Abelian Projection is discussed. This term refers to the use of a new (``Laplacian'') gauge fixing prescription for implementing the Abelian Projection of QCD. The gauge condition is based on the lowest-lying eigenvector of the covariant Laplacian operator in the adjoint representation. This Laplacian gauge fixing procedure is free of the ambiguities which plague lattice simulations which work with the popular Maximally Abelian Gauge. Furthermore, Laplacian gauge fixed configurations enjoy a natural kind of smoothness. These two properties are crucial for a reliable determination of physical quantities using the Abelian Projection. We also examine a new, Higgs-field-like observable which emerges as a by-product of the method. This quantity can be used to identify magnetic monopoles in a way independent of the traditional prescription. It is argued that physically relevant magnetic monopoles are accomodated well by the Laplacian method, while they are suppressed (too) strongly in Maximally Abelian Gauge. Finally, first evidence of abelian dominance in the Laplacian Abelian Projection is presented.

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A. J. van der Sijs. 1998-03-02. Abelian Projection without Ambiguities. https://doi.org/10.1143/ptps.131.149

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