Beyond basis invariants

Abstract Physical observables cannot depend on the basis one chooses to describe fields. Therefore, all physically relevant properties of a model are, in principle, expressible in terms of basis-invariant combinations of the parameters. However, in many cases it becomes prohibitively difficult to es...

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Bibliographic Details
Main Authors: Igor P. Ivanov, Celso C. Nishi, Andreas Trautner
Format: Article
Language:English
Published: SpringerOpen 2019-04-01
Series:European Physical Journal C: Particles and Fields
Online Access:http://link.springer.com/article/10.1140/epjc/s10052-019-6845-x
Description
Summary:Abstract Physical observables cannot depend on the basis one chooses to describe fields. Therefore, all physically relevant properties of a model are, in principle, expressible in terms of basis-invariant combinations of the parameters. However, in many cases it becomes prohibitively difficult to establish key physical features exclusively in terms of basis invariants. Here, we advocate an alternative route in such cases: the formulation of basis-invariant statements in terms of basis-covariant objects. We review several examples where the basis-covariant path is superior to the traditional approach in terms of basis invariants. In particular, this includes the formulation of necessary and sufficient basis-invariant conditions for various physically distinct forms of $$\textit{CP}$$ CP conservation in two- and three-Higgs-doublet models.
ISSN:1434-6044
1434-6052