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arXiv · 1410.2740

Observables in Higgsed Theories

Axel Maas
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Abstract

In gauge theories, observable quantities have to be gauge-invariant. In general, this requires composite operators, which usually have substantially different properties, e.g. masses, than the elementary particles. Theories with a Higgs field, in which the Brout-Englert-Higgs effect is active, provide an interesting exception to this rule. Due to an intricate mechanism, the Fröhlich-Morchio-Strocchi mechanism, the masses of the composite operators with the same $J^P$ quantum numbers, but modified internal quantum numbers, have the same masses. This mechanism is supported using lattice gauge theory for the standard-model Higgs sector, i.e. Yang-Mills-Higgs theory with gauge group SU(2) and custodial symmetry group SU(2). Furthermore, the extension to the 2-Higgs-doublet-model is briefly discussed, and some preliminary results are presented.

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Axel Maas. 2014-10-10. Observables in Higgsed Theories. https://arxiv.org/abs/1410.2740

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