8,310 research outputs found
Smooth Solutions and Discrete Imaginary Mass of the Klein-Gordon Equation in the de Sitter Background
Using methods in the theory of semisimple Lie algebras, we can obtain all
smooth solutions of the Klein-Gordon equation on the 4-dimensional de Sitter
spacetime (dS^4). The mass of a Klein-Gordon scalar on dS^4 is related to an
eigenvalue of the Casimir operator of so(1,4). Thus it is discrete, or
quantized. Furthermore, the mass m of a Klein-Gordon scalar on dS^4 is
imaginary: m^2 being proportional to -N(N+3), with N >= 0 an integer.Comment: 23 pages, 4 figure
Understanding for flavor physics in the lepton sector
In this paper, we give a model for understanding flavor physics in the lepton
sector--mass hierarchy among different generations and neutrino mixing pattern.
The model is constructed in the framework of supersymmetry, with a family
symmetry . There are two right-handed neutrinos introduced for seesaw
mechanism, while some standard model(SM) gauge group singlet fields are
included which transforms non-trivially under family symmetry. In the model,
each order of contributions are suppressed by compared to the
previous one. In order to reproduce the mass hierarchy, and
, and are obtained
at leading-order(LO) and next-to-leading-order(NLO) respectively, while
electron can only get its mass through
next-to-next-to-next-to-leading-order(NNNLO) contributions. For neutrino mixing
angels, are
i.e. Bi-maximal mixing pattern as first approximation, while higher order
contributions can make them consistent with experimental results. As
corrections for and originate from the same
contribution, there is a relation predicted for them
. Besides, deviation from
for should have been as large as
deviation from 0 for if it were not the former is suppressed by a
factor 4 compared to the latter.Comment: version to appear in Phys. Rev.
On the four-zero texture of quark mass matrices and its stability
We carry out a new study of quark mass matrices (up-type) and
(down-type) which are Hermitian and have four zero entries, and
find a new part of the parameter space which was missed in the previous works.
We identify two more specific four-zero patterns of and
with fewer free parameters, and present two toy flavor-symmetry
models which can help realize such special and interesting quark flavor
structures. We also show that the texture zeros of and
are essentially stable against the evolution of energy scales in
an analytical way by using the one-loop renormalization-group equations.Comment: 33 pages, 4 figures, minor comments added, version to appear in Nucl.
Phys.
Localization of gauge vector field on flat branes with five-dimension (asymptotic) AdS spacetime
In order to localize gauge vector field on Randall-Sundrum-like
braneworld model with infinite extra dimension, we propose a new kind of
non-minimal coupling between the gauge field and the gravity. We propose
three kinds of coupling methods and they all support the localization of zero
mode. In addition, one of them can support the localization of massive modes.
Moreover, the massive tachyonic modes can be excluded. And our method can be
used not only in the thin braneword models but also in the thick ones.Comment: Added acknowledgments to the refree. Appeared on JHE
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