Overlap of the Wilson loop with the broken-string state

F. Gliozzi; A. Rago

doi:10.1016/j.nuclphysb.2005.02.023

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arXiv · hep-lat/0411004

Overlap of the Wilson loop with the broken-string state

F. Gliozzi·A. Rago

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Abstract

Numerical experiments on most gauge theories coupled with matter failed to observe string-breaking effects while measuring Wilson loops only. We show that, under rather mild assumptions, the overlap of the Wilson loop operator with the broken-string state obeys a natural upper bound implying that the signal of string-breaking is in general too weak to be detected by the conventional updating algorithms. In order to reduce the variance of the Wilson loops in 3-D Z_2 gauge Higgs model we use a new algorithm based on the Lüscher-Weisz method combined with a non-local cluster algorithm which allows to follow the decay of rectangular Wilson loops up to values of the order of 10^{-24}. In this way a sharp signal of string breaking is found.

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BibTeX RIS

F. Gliozzi, A. Rago. 2004-11-02. Overlap of the Wilson loop with the broken-string state. https://doi.org/10.1016/j.nuclphysb.2005.02.023

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