12,065,457 research outputs found
Mosses new to Hong Kong (3)
Ten moss species - Philonotis turneriana (Schwaegr.) Mitt., Fissidens javanicus Dozy & Molk., Lopidium nazeense (Ther.) Broth., Himatocladium cyclophyllum (C. Muell.) Fleisch., Homaliodendron exigiuum (Bosch & Lac.) Fleisch., Homaliodendron microdendron (Mont.) Fleisch., Homaliodendron scapellifolium (Mitt.) Fleisch., Pinnatella anacamptolepis (C.Muell.) Broth., Calyptothecium wrightii (Mitt.) Fleisch. and Haplocladium angustifolium (Hampe & C. Muell.) Broth. are reported new to Hong Kong. Among them, four are new to Guangdong Province of China. An updated checklist of Hong Kong mosses is provided
SO(3)-Structures on 8-manifolds
We study Riemannian 8-manifolds with an infinitesimal action of SO(3) by
which each tangent space breaks into irreducible spaces of dimensions 3 and 5.
The relationship with quaternionic, almost product- and PSU-geometry is
thoroughly explained using representation-theoretical arguments.Comment: 19 pages, 2 figure
D-brane charges on SO(3)
In this letter we discuss charges of D-branes on the group manifold SO(3).
Our discussion will be based on a conformal field theory analysis of boundary
states in a Z_2-orbifold of SU(2). This orbifold differs from the one recently
discussed by Gaberdiel and Gannon in its action on the fermions and leads to a
drastically different charge group. We shall consider maximally symmetric
branes as well as branes with less symmetry, and find perfect agreement with a
recent computation of the corresponding K-theory groups.Comment: 11 pages, 1 figure. Some comments adde
SO(3) family symmetry and axions
Motivated by the idea of Comprehensive Unification, we consider a gauged
flavor extension of the Standard Model, including right-handed
neutrinos and a Peccei-Quinn symmetry. The model accommodates the observed
fermion masses and mixings and yields a characteristic, successful relation
among them. The Peccei-Quinn symmetry is an essential ingredient.Comment: Contribution to the 2019 EW session of the 54th Rencontres de Morion
Surface Spline Approximation on SO(3)
The purpose of this article is to introduce a new class of kernels on SO(3)
for approximation and interpolation, and to estimate the approximation power of
the associated spaces. The kernels we consider arise as linear combinations of
Green's functions of certain differential operators on the rotation group. They
are conditionally positive definite and have a simple closed-form expression,
lending themselves to direct implementation via, e.g., interpolation, or
least-squares approximation. To gauge the approximation power of the underlying
spaces, we introduce an approximation scheme providing precise L_p error
estimates for linear schemes, namely with L_p approximation order conforming to
the L_p smoothness of the target function.Comment: 22 pages, to appear in Appl. Comput. Harmon. Ana
Electron Scattering on 3He - a Playground to Test Nuclear Dynamics
The big spectrum of electron induced processes on 3He is illustrated by
several examples based on Faddeev calculations with modern nucleon-nucleon and
three-nucleon forces as well as exchange currents. The kinematical region is
restricted to a mostly nonrelativistic one where the three-nucleon c.m. energy
is below the pion production threshold and the three-momentum of the virtual
photon is sufficiently below the nucleon mass. Comparisons with available data
are shown and cases of agreement and disagreement are found. It is argued that
new and precise data are needed to systematically check the present day
dynamical ingredients.Comment: 27 pages, 24 figure
Ground State Properties of an Asymmetric Hubbard Model for Unbalanced Ultracold Fermionic Quantum Gases
In order to describe unbalanced ultracold fermionic quantum gases on optical
lattices in a harmonic trap, we investigate an attractive () asymmetric
() Hubbard model with a Zeeman-like magnetic
field. In view of the model's spatial inhomogeneity, we focus in this paper on
the solution at Hartree-Fock level. The Hartree-Fock Hamiltonian is
diagonalized with particular emphasis on superfluid phases. For the special
case of spin-independent hopping we analytically determine the number of
solutions of the resulting self-consistency equations and the nature of the
possible ground states at weak coupling. Numerical results for unbalanced
Fermi-mixtures are presented within the local density approximation. In
particular, we find a fascinating shell structure, involving normal and
superfluid phases. For the general case of spin-dependent hopping we calculate
the density of states and the possible superfluid phases in the ground state.
In particular, we find a new magnetized superfluid phase.Comment: 9 pages, 5 figure
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