Alberto Tonero (Trieste):
First steps toward an asymptotically safe model of electroweak interactions
In a minimal realization of the standard
model that contains no Higgs boson the breaking of SU(2)xU(1) symmetry is provided by
the coupling of gauge bosons and fermions to a nonlinear sigma model. Normally this is
regarded only as an approximate description valid below some cutoff energy scale.
However, if there is a UV fixed point, the higgsless theory in which the
Nambu-Goldstone bosons are thought of as fundamental degrees of freedom could hold up
to higher energies, becoming asymptotically safe. In this talk I will present the RG
analysis of the pure bosonic model and the predictions about the contributions to the
oblique S and T parameters. Moreover, I will also discuss the inclusion of fermions
and the (possible) modification they introduce to the asymptotic safety picture.
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