345 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
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
Implication of Omega_m through the Morphological Analysis of Weak Lensing Fields
We apply the morphological descriptions of two-dimensional contour map, the
so-called Minkowski functionals (the area fraction, circumference, and Euler
characteristics), to the convergence field of the
large-scale structure reconstructed from the shear map produced by the
ray-tracing simulations. The perturbation theory of structure formation has
suggested that the non-Gaussian features on the Minkowski functionals with
respect to the threshold in the weakly nonlinear regime are induced by the
three skewness parameters of that are sensitive to the density
parameter of matter, . We show that, in the absence of noise
due to the intrinsic ellipticities of source galaxies with which the
perturbation theory results can be recovered, the accuracy of
determination is improved by using the Minkowski functionals
compared to the conventional method of using the direct measure of skewness.Comment: 4 pages, 3 figures, to appear in ApJ Lette
Model building by coset space dimensional reduction in ten-dimensions with direct product gauge symmetry
We investigate ten-dimensional gauge theories whose extra six-dimensional
space is a compact coset space, , and gauge group is a direct product of
two Lie groups. We list up candidates of the gauge group and embeddings of
into them. After dimensional reduction of the coset space,we find fermion and
scalar representations of with
and which accomodate all of the standard
model particles. We also discuss possibilities to generate distinct Yukawa
couplings among the generations using representations with a different
dimension for and models.Comment: 14 pages; added local report number, added refferenc
Non-Gaussianity Consistency Relation for Multi-field Inflation
While detection of the "local form" bispectrum of primordial perturbations
would rule out all single-field inflation models, multi-field models would
still be allowed. We show that multi-field models described by the
formalism obey an inequality between and one of the local-form
{\it trispectrum} amplitudes, , such that with a possible logarithmic scale dependence,
provided that 2-loop terms are small. Detection of a violation of this
inequality would rule out most of multi-field models, challenging inflation as
a mechanism for generating the primoridal perturbations.Comment: 5 pages. Accepted for publication in Physical Review Letter
Dynamical symmetry breaking in Gauge-Higgs unification of 5D SUSY theory
We study the dynamical symmetry breaking in the gauge-Higgs unification of
the 5D SUSY theory, compactified on an orbifold, .
This theory identifies Wilson line degrees of freedoms as ``Higgs doublets''.
We consider and SU(6) models, in which the gauge
symmetries are reduced to and , respectively, through the
orbifolding boundary conditions. Quarks and leptons are bulk fields, so that
Yukawa interactions can be derived from the 5D gauge interactions. We estimate
the one loop effective potential of ``Higgs doublets'', and analyze the vacuum
structures in these two models. We find that the effects of bulk quarks and
leptons destabilize the suitable electro-weak vacuum. We show that the
introduction of suitable numbers of extra bulk fields possessing the suitable
representations can realize the appropriate electro-weak symmetry breaking.Comment: 15 pages, 4 figures;disscutions on Higgs quartic couplings adde
R-mode Instability of Slowly Rotating Non-isentropic Relativistic Stars
We investigate properties of -mode instability in slowly rotating
relativistic polytropes. Inside the star slow rotation and low frequency
formalism that was mainly developed by Kojima is employed to study axial
oscillations restored by Coriolis force. At the stellar surface, in order to
take account of gravitational radiation reaction effect, we use a near-zone
boundary condition instead of the usually imposed boundary condition for
asymptotically flat spacetime. Due to the boundary condition, complex
frequencies whose imaginary part represents secular instability are obtained
for discrete -mode oscillations in some polytropic models. It is found that
such discrete -mode solutions can be obtained only for some restricted
polytropic models. Basic properties of the solutions are similar to those
obtained by imposing the boundary condition for asymptotically flat spacetime.
Our results suggest that existence of a continuous part of spectrum cannot be
avoided even when its frequency becomes complex due to the emission of
gravitational radiation.Comment: 10 pages, 4 figures, accepted for publlication in PR
A general formula of the effective potential in 5D SU(N) gauge theory on orbifold
We show a general formula of the one loop effective potential of the 5D SU(N)
gauge theory compactified on an orbifold, . The formula shows the case
when there are fundamental, (anti-)symmetric tensor and adjoint
representational bulk fields. Our calculation method is also applicable when
there are bulk fields belonging to higher dimensional representations. The
supersymmetric version of the effective potential with Scherk-Schwarz breaking
can be obtained straightforwardly. We also show some examples of effective
potentials in SU(3), SU(5) and SU(6) models with various boundary conditions,
which are reproduced by our general formula.Comment: 22 pages;minor corrections;references added;typos correcte
Gauge Coupling Unification in GUT with Anomalous U(1) Symmetry
We show that in the framework of grand unified theory (GUT) with anomalous
gauge symmetry, the success of the gauge coupling unification in the
minimal SU(5) GUT is naturally explained, even if the mass spectrum of
superheavy fields does not respect SU(5) symmetry. Because the unification
scale for most realizations of the theory becomes smaller than the usual GUT
scale, it suggests that the present level of experiments is close to that
sufficient to observe proton decay via dimension 6 operators, .Comment: 4 pages, RevTeX, to appear in Phys.Rev.Let
Numerical evolution of multiple black holes with accurate initial data
We present numerical evolutions of three equal-mass black holes using the
moving puncture approach. We calculate puncture initial data for three black
holes solving the constraint equations by means of a high-order multigrid
elliptic solver. Using these initial data, we show the results for three black
hole evolutions with sixth-order waveform convergence. We compare results
obtained with the BAM and AMSS-NCKU codes with previous results. The
approximate analytic solution to the Hamiltonian constraint used in previous
simulations of three black holes leads to different dynamics and waveforms. We
present some numerical experiments showing the evolution of four black holes
and the resulting gravitational waveform.Comment: Published in PR
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