544 research outputs found
Large Gauge Hierarchy in Gauge-Higgs Unification
We study a five dimensional SU(3) nonsupersymmetric gauge theory compactified
on and discuss the gauge hierarchy in the scenario of the
gauge-Higgs unification. Making use of calculability of the Higgs potential and
a curious feature that coefficients in the potential are given by discrete
values, we find two models, in which the large gauge hierarchy is realized,
that is, the weak scale is naturally obtained from an unique large scale such
as a grand unified theory scale or the Planck scale. The size of the Higgs mass
is also discussed in each model. One of the models we find realizes both large
gauge hierarchy and consistent Higgs mass, and shows that the Higgs mass
becomes heavier as the compactified scale becomes smaller.Comment: 21 pages, no figures, version to appear in PR
Two loop finiteness of Higgs mass and potential in the gauge-Higgs unification
The zero mode of an extra-dimensional component of gauge potentials serves as
a 4D Higgs field in the gauge-Higgs unification. We examine QED on and determine the mass and potential of a 4D Higgs field (the
component) at the two loop level with gauge invariant reguralization. It is
seen that the mass is free from divergences and independent of the
renormalization scheme.Comment: 18 pages, 1 figur
On Gauge Symmetry Breaking via Euclidean Time Component of Gauge Fields
We study gauge theories with/without an extra dimension at finite
temperature, in which there are two kinds of order parameters of gauge symmetry
breaking. The one is the zero mode of the gauge field for the Euclidean time
direction and the other is that for the direction of the extra dimension. We
evaluate the effective potential for the zero modes in one-loop approximation
and investigate the vacuum configuration in detail. Our analyses show that
gauge symmetry can be broken only through the zero mode for the direction of
the extra dimension and no nontrivial vacuum configuration of the zero mode for
the Euclidean time direction is found.Comment: 22 pages, 6 figures, references and typos corrected, version to
appear in PR
Gauge Symmetry Breaking through the Hosotani Mechanism in Softly Broken Supersymmetric QCD
Gauge symmetry breaking through the Hosotani mechanism (the dynamics of
nonintegrable phases) in softly broken supersymmetric QCD with
flavors is studied. For even, there is a single SU(N) symmetric vacuum
state, while for odd, there is a doubly degenerate SU(N) symmetric vacuum
state in the model. We also study generalized supersymmetric QCD by adding
numbers of massless adjoint matter. The gauge symmetry breaking
pattern such as is possible for appropriate choices
of the matter content and values of the supersymmetry breaking parameter. The
massless state of the adjoint Higgs scalar is also discussed in the models.Comment: 19 pages, no figure, final version to appear in Phys. Rev.
Bulk Mass Effects in Gauge-Higgs Unification at Finite Temperature
We study the bulk mass effects on the electroweak phase transition at finite
temperature in a five dimensional SU(3) gauge-Higgs unification model on an
orbifold. We investigate whether the Higgs mass satisfying the experimental
lower bound can be compatible with the strong first order phase transition
necessary for a successful electroweak baryogenesis. Our numerical results show
that the above statement can be realized by matter with bulk mass yielding a
viable Higgs mass. We also find an interesting case where the heavier Higgs
gives the stronger first order phase transition.Comment: 17 pages, 1 figur
Dynamics of Nonintegrable Phases in Softly Broken Supersymmetric Gauge Theory with Massless Adjoint Matter
We study SU(N) supersymmetric Yang-Mills theory with massless adjoint matter
defined on . The SU(N) gauge symmetry is broken maximally to
, independent of the number of flavor and the boundary conditions
of the fields associated with the Scherk-Schwarz mechanism of supersymmetry
breaking. The mass of the Higgs scalar is generated through quantum corrections
in the extra dimensions. The quantum correction can become manifest by a finite
Higgs boson mass at low energies even in the limit of small extra dimensions
thanks to the supersymmetry breaking parameter of the Scherk-Schwarz mechanism.Comment: 19 pages, 2 figures, corrected some typo
Multi-Higgs Mass Spectrum in Gauge-Higgs Unification
We study an SU(2) supersymmetric gauge model in a framework of gauge-Higgs
unification. Multi-Higgs spectrum appears in the model at low energy. We
develop a useful perturbative approximation scheme for evaluating effective
potential to study the multi-Higgs mass spectrum. We find that both
tree-massless and massive Higgs scalars obtain mass corrections of similar size
from finite parts of the loop effects. The corrections modify multi-Higgs mass
spectrum, and hence, the loop effects are significant in view of future
verifications of the gauge-Higgs unification scenario in high-energy
experiments.Comment: 32 pages; typos corrected and a few comments added, published versio
Aspects of Phase Transition in Gauge-Higgs Unification at Finite Temperature
We study the phase transition in gauge-Higgs unification at finite
temperature. In particular, we obtain the strong first order electroweak phase
transition for a simple matter content yielding the correct order of Higgs mass
at zero temperature. Two stage phase transition is found for a particular
matter content, which is the strong first order at each stage. We further study
supersymmetric gauge models with the Scherk-Schwarz supersymmetry breaking. We
again observe the first order electroweak phase transition and multi stage
phase transition.Comment: 18 pages, 7 figures, references corrected, minor correctio
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