1,271 research outputs found
Large rescaling of the Higgs condensate: theoretical motivations and lattice results
In the Standard Model the Fermi constant is associated with the vacuum
expectation value of the Higgs field, `the condensate', usually believed to be
a cutoff-independent quantity. General arguments related to the `triviality' of
theory in 4 space-time dimensions suggest, however, a dramatic
renormalization effect in the continuum limit that is clearly visible on the
relatively large lattices available today. The result can be crucial for the
Higgs phenomenology and in any context where spontaneous symmetry breaking is
induced through scalar fields.Comment: LATTICE99(Higgs) 3 pages, 3 figure
Indications on the Higgs boson mass from lattice simulations
The `triviality' of has been traditionally interpreted within
perturbation theory where the prediction for the Higgs boson mass depends on
the magnitude of the ultraviolet cutoff . This approach crucially
assumes that the vacuum field and its quantum fluctuations rescale in the same
way. The results of the present lattice simulation, confirming previous
numerical indications, show that this assumption is not true. As a consequence,
large values of the Higgs mass can coexist with the limit . As an example, by extrapolating to the Standard Model our results
obtained in the Ising limit of the one-component theory, one can obtain a value
as large as GeV, independently of .Comment: 3 pages, 2 figures, Lattice2003(higgs
An alternative heavy Higgs mass limit
After commenting on the present value of the Higgs particle mass from
radiative corrections, we explore the phenomenological implications of an
alternative, non-perturbative renormalization of the scalar sector where the
mass of the Higgs particle does not represent a measure of observable
interactions at the Higgs mass scale. In this approach the Higgs particle could
be very heavy, even heavier than 1 TeV, and remain nevertheless a relatively
narrow resonance.Comment: 17 pages. Version accepted for publication in Journal of Physics
First lattice evidence for a non-trivial renormalization of the Higgs condensate
General arguments related to ``triviality'' predict that, in the broken phase
of theory, the condensate re-scales by a factor
$Z_{\phi}$ different from the conventional wavefunction-renormalization factor,
$Z_{prop}$. Using a lattice simulation in the Ising limit we measure
$Z_{\phi}=m^2 \chi$ from the physical mass and susceptibility and $Z_{prop}$
from the residue of the shifted-field propagator. We find that the two $Z$'s
differ, with the difference increasing rapidly as the continuum limit is
approached. Since $Z_{\phi}$ affects the relation of to the Fermi
constant it can sizeably affect the present bounds on the Higgs mass.Comment: 10 pages, 3 figures, 1 table, Latex2
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