A new source of structured singular value decomposition problems.
A Noether-Lefschetz theorem for vector bundles.
A nonlinearizable action of on
The main purpose of this article is to give an explicit algebraic action of the group of permutations of 3 elements on affine four-dimensional complex space which is not conjugate to a linear action.
A normal form for curves in Grassmannians.
A note about the isotropy groups of 2-plane bundles over closed surfaces.
A note of the Torelli spaces of non-orientable compact Klein surfaces.
A note on 2-dimensional arithmetic symbols on Gl(n, ΣS).
The aim of this note is to offer a summary of the definitions and properties of arithmetic symbols on the linear group Gl(n, F) -F being an arbitrary discrete valuation field- and to show that the natural generalizations of the Parshin symbol on an algebraic surface S to the linear group Gl(n, ΣS) do not allow us to define new 2-dimensional symbols on S.[Proceedings of the Primeras Jornadas de Teoría de Números (Vilanova i la Geltrú (Barcelona), 30 June - 2 July 2005)].
A note on a Brill-Noether locus over a non-hyperelliptic curve of genus 4
We prove that a certain Brill-Noether locus over a non-hyperelliptic curve C of genus 4, is isomorphic to the Donagi-Izadi cubic threefold in the case when the pencils of the two trigonal line bundles of C coincide.
A note on a quartic with a tacnode and a flexnode
A note on a theorem of Griffiths on the Abel-Jacobi map.
A note on a theorem of Horikawa.
In this paper we classify the algebraic surfaces on C with KS2=4, pg=3 and canonical map of degree d=3. By our result and the previous one of Horikawa (1979) we obtain the complete determination of surfaces with K2=4 and pg=3.
A Note on a Theorem of Lion
In this note we bind together Wilkie's complement theorem with Lion's theorem on geometric, regular and 0-regular families of functions.
A note on a theorem of Xiao Gang.
In 1985 Xiao Gang proved that the bicanonical surface of a complex surface S of general type with p2(S) > 2 is not composed of a pencil. In this note a new proof of this theorem is presented.
A note on abelian varieties embedded in quadrics
A note on Bézout's theorem
We present a version of Bézout's theorem basing on the intersection theory in complex analytic geometry. Some applications for products of surfaces and curves are also given.
A note on Bierstone-Milman-Pawłucki's paper "Composite differentiable functions"
We demonstrate that the composite function theorems of Bierstone-Milman-Pawłucki and of Glaeser carry over to any polynomially bounded, o-minimal structure which admits smooth cell decomposition. Moreover, the assumptions of the o-minimal versions can be considerably relaxed compared with the classical analytic ones.
A note on boundaries of open polynomial images of .
A note on certain Tannakian group schemes
In this note, we prove that the -fundamental group scheme is a birational invariant for smooth projective varieties. We prove that the -fundamental group scheme is naturally a quotient of the Nori fundamental group scheme. For elliptic curves, it turns out that the -fundamental group scheme and the Nori fundamental group scheme coincide. We also consider an extension of the Nori fundamental group scheme in positive characteristic using semi-essentially finite vector bundles, and prove that in...
A Note on compact Kähler manifolds with Nef Tangent Bundles.
A note on complex projective threefolds admitting holomorphic contact structures.