66,566 research outputs found
Isotrivial VMRT-structures of complete intersection type
The family of varieties of minimal rational tangents on a quasi-homogeneous
projective manifold is isotrivial. Conversely, are projective manifolds with
isotrivial varieties of minimal rational tangents quasi-homogenous? We will
show that this is not true in general, even when the projective manifold has
Picard number 1. In fact, an isotrivial family of varieties of minimal rational
tangents needs not be locally flat in differential geometric sense. This leads
to the question for which projective variety Z, the Z-isotriviality of
varieties of minimal rational tangents implies local flatness. Our main result
verifies this for many cases of Z among complete intersections.Comment: Some errors in Section 8 and Lemma 8.1 corrected. To appear in The
Asian Journal of Mathematics (AJM) special issue dedicated to Ngaiming Mok's
60th birthda
Vortex Structures in Model p-Wave Superconducting Sr2RuO4 -- Single 2-Dimensional Band v.s. Quasi-1-Dimensional Band
There have been an interesting debate on the primary source of chiral p-wave
superconductivity in Sr2RuO4. We present a comparative study on the vortex
structure between a single 2-dimensional (2D) band and quasi-1D band model by
using Bogoliubov-de Gennes theory. The pattern of the iso-values of the local
density of state around a vortex has a diamond shape in the quasi-1D model and
is much more isotropic in the 2D model. The spin lattice relaxation rate well
below the superconducting transition temperature is greatly enhanced in the
vortex state in the 2D model but not in the quasi-1D model. These features can
be tested by using scanning tunneling microscope and NMR to distinguish the
models for the superconductivity in Sr2RuO4.Comment: 7 pages, 6 fig
On the structure of
Let be the infinitesimal quantum over , where
is a field containing an th primitive root of 1 with
{\it odd}. We will determine the basic algebra for , where is the natural module for
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