497 research outputs found
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
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
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
Correct Effective Potential of Supersymmetric Yang-Mills Theory on M^4\times S^1
We study an supersymmetric Yang-Mills theory defined on
. The vacuum expectation values for adjoint scalar field in
vector multiplet, though important, has been overlooked in evaluating one-loop
effective potential of the theory. We correctly take the vacuum expectation
values into account in addition to the Wilson line phases to give an expression
for the effective potential, and gauge symmetry breaking is discussed. In
evaluating the potential, we employ the Scherk-Schwarz mechanism and introduce
bare mass for gaugino in order to break supersymmetry. We also obtain masses
for the scalars, the adjoint scalar, and the component gauge field for the
direction in case of the SU(2) gauge group. We observe that large
supersymmetry breaking gives larger mass for the scalar. This analysis is
easily applied to the case.Comment: 12 pages, 1 figur
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
Comparison of Confinement Degradation in High Density and Particle Transport between Tokamak and Helical
Suppression of metastasis-associated S100A4 gene expression by gamma-interferon in human colon adenocarcinoma cells
Development of a Chisel Digger for Harvesting Groundnut
A chisel digger was designed and developed at ICRlSAT Asia Center for harvesting virginia bunch type groundnut crops. It consists of a digger-bottom and a standard. The digger-bottom has two shares that are inclined at 120" to each other and contain chisel points for inc~eased penetration into the soil. A single digger-bottom attached to a draw pole can be pulled by a pair of oxen and two or more digger-bottoms attached to a tool bar can be pulled by a tractor. The bullock-drawn chisel digger can harvest a 60-cm wide strip or two rows of the crop sown at a 30-cm row
spacing. It can harvest about 0.7 ha per day (8 h) with less than 5% losses. It undercuts the tap roots of groundnut plants and leaves the plants upright without any dragging. The chisel digger performed satisfactorily even under soil conditions where blade type diggers could not penetrate up-to the desired depth
- …