共查询到20条相似文献,搜索用时 31 毫秒
1.
In this paper, we completely determine the trivial factors for L-functions of symmetric products of Kloosterman sheaves. 相似文献
2.
Noriyuki Suwa 《K-Theory》1995,9(3):245-271
We prove a purity theorem for logarithmic Hodge-Witt sheaves and construct a complex, which gives thep-part of the reciprocity sequence for a function field over a finite field of characteristicp. 相似文献
3.
Poornapushkala Narayanan 《代数通讯》2018,46(4):1698-1708
Consider an ample and globally generated line bundle L on a smooth projective variety X of dimension N≥2 over ?. Let D be a smooth divisor in the complete linear system of L. We construct reflexive sheaves on X by an elementary transformation of a trivial bundle on X along certain globally generated torsion-free sheaves on D. The dual reflexive sheaves are called the Lazarsfeld-Mukai reflexive sheaves. We prove the μL-(semi)stability of such reflexive sheaves under certain conditions. 相似文献
4.
5.
Usha N. Bhosle 《代数通讯》2013,41(3):821-841
We give a construction of torsionfree sheaves on a seminormal variety Y using torsionfree sheaves on the normalization X and the non-normal locus W. We use it to find a relation between Picard groups of X, Y, and W. We apply it to determine the Picard groups of the generalized Jacobian, the compactified Jacobian and some subschemes associated to the moduli spaces of torsionfree sheaves of rank 2 and odd degree on a nodal curve. 相似文献
6.
Lothar Göttsche 《manuscripta mathematica》1996,89(1):193-201
In this paper we show that for rational ruled surfaces many moduli spaces of torsion free sheaves with given Chern classes
are rational. We deal with the case that the first Chern classc
1 satisfiesc
1.F=0 for a fibreF of the ruling. The main tool are priority sheaves introduced by Hirschowitz-Laszlo and Walter, which enable us to reduce
the problem to the construction of a family of sheaves over a big enough rational base. 相似文献
7.
Anastasios Mallios Patrice P. Ntumba 《Rendiconti del Circolo Matematico di Palermo》2009,58(1):155-168
The approach to a counterpart, in Abstract Geometric Algebra, that is, Geometric Algebra via sheaves of modules, of the classical
Witt’s decomposition theoremis based on the axiomatization of the classical context, which however leads to the formulation
of a specific subcategory of the category of sheaves of modules: the full subcategory of convenient sheaves of modules. Convenient sheaves of modules turn out, by the very essence of the matter at hand, to be of further importance as far as
the setting of results leading to the sheaf-theoretic aspect of several forms of the Witt’s theorem is concerned. Further versions of the Witt’s theorem are still to be treated elsewhere.
相似文献
8.
Jean–Marc Drézet 《Mathematische Nachrichten》2009,282(7):919-952
This paper is devoted to the study of some coherent sheaves on non reduced curves that can be locally embedded in smooth surfaces. If Y is such a curve and n is its multiplicity, then there is a filtration C1 = C ? C2 ? … ? Cn = Y such that C is the reduced curve associated to Y, and for every P ∈ C, if z ∈ OY,P is an equation of C then (zi) is the ideal of Ci in OY,P. A coherent sheaf on Y is called torsion free if it does not have any non zero subsheaf with finite support. We prove that torsion free sheaves are reflexive. We study then the quasi locally free sheaves, i.e., sheaves which are locally isomorphic to direct sums of the OCi.We define an invariant for these sheaves, the complete type, and prove the irreducibility of the set of sheaves of given complete type. We study the generic quasi locally free sheaves, with applications to the moduli spaces of stable sheaves on Y (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
9.
10.
We classify all isomorphism classes of stable torsionfree sheaves on an irreducible nodal curve of arithmetic genus one defined
over ℂ. Let X be a nodal curve of arithmetic genus one defined over ℝ, with exactly one node, such that X does not have any real points apart from the node. We classify all isomorphism classes of stable real algebraic torsionfree
sheaves over X of even rank. We also classify all isomorphism classes of real algebraic torsionfree sheaves over X of rank one. 相似文献
11.
Under certain assumptions, we prove that the Deligne tensor product of the categories of constructible perverse sheaves on pseudomanifolds X and Y is the category of constructible perverse sheaves on X×Y. The functor of the exterior Deligne tensor product is identified with the exterior geometric tensor product. 相似文献
12.
A new irreducible component of the Gieseker–Maruyama moduli scheme M(3) of semistable coherent sheaves of rank 2 with Chern classes c1 = 0, c2 = 3, and c3 = 0 on P3 such that its general point corresponds to a sheaf whose singular locus contains components of dimensions 0 and 1 is described. These sheaves are obtained by elementary transformations of stable reflexive sheaves of rank 2 with Chern classes c1 = 0, c2 = 2, and c3 = 2 along the projective line. The constructed family of sheaves is the first example of an irreducible component of a Gieseker–Maruyama scheme whose general point corresponds to a sheaf with singularities of mixed dimension.
相似文献13.
Let X be a complex space of pure dimension. We introduce fine sheaves of (0,q)-currents, which coincides with the sheaves of smooth forms on the regular part of X, so that the associated Dolbeault complex yields a resolution of the structure sheaf . Our construction is based on intrinsic and quite explicit semi-global Koppelman formulas. 相似文献
14.
S. A. Kuleshov 《Mathematical Notes》1997,62(6):707-725
We investigate the relation between stable representations of quivers and stable sheaves. A construction of thin smooth compact
moduli spaces for stable sheaves on quadrics based on this relation is presented.
Translated fromMatematicheskie Zametki, Vol 62, No. 6, pp. 843–864, December, 1997
Translated by S. K. Lando 相似文献
15.
Usha N. Bhosle 《Proceedings Mathematical Sciences》1992,102(1):13-22
We extend the notion of a parabolic vector bundle on a smooth curve to define generalized parabolic sheaves (GPS) on any integral
projective curve X. We construct the moduli spacesM(X) of GPS of certain type onX. IfX is obtained by blowing up finitely many nodes inY then we show that there is a surjective birational morphism from M(X) to M (Y). In particular, we get partial desingularisations of the moduli of torsion-free sheaves on a nodal curveY. 相似文献
16.
We establish a blow-up formula for Hodge cohomology of locally free sheaves on smooth proper varieties over an algebraically closed field of positive characteristic. For this, we introduce a notion of relative Hodge sheaves and study their behavior under blow-ups along smooth centers. In particular, as an application, we study the blow-up invariance of the E2-degeneracy of the Hochschild–Kostant–Rosenberg spectral sequence for smooth proper varieties. 相似文献
17.
In this article we introduce a new class of non-commutative projective curves and show that in certain cases the derived category
of coherent sheaves on them has a tilting complex. In particular, we prove that the right bounded derived category of coherent
sheaves on a reduced rational projective curve with only nodes and cusps as singularities, can be fully faithfully embedded
into the right bounded derived category of the finite dimensional representations of a certain finite dimensional algebra
of global dimension two. As an application of our approach we show that the dimension of the bounded derived category of coherent
sheaves on a rational projective curve with only nodal or cuspidal singularities is at most two. In the case of the Kodaira
cycles of projective lines, the corresponding tilted algebras belong to a well-known class of gentle algebras. We work out
in details the tilting equivalence in the case of the Weierstrass nodal curve zy
2 = x
3 + x
2
z. 相似文献
18.
Roman Bezrukavnikov 《Inventiones Mathematicae》2006,166(2):327-357
The paper is concerned with cohomology of the small quantum group at a root of unity, and of its upper triangular subalgebra,
with coefficients in a tilting module. It turns out to be related to irreducible objects in the heart of a certain t-structure on the derived category of equivariant coherent sheaves on the Springer resolution, and to equivariant coherent
IC sheaves on the nil-cone. The support of the cohomology is described in terms of cells in affine Weyl groups. The basis
in the Grothendieck group provided by the cohomology modules is shown to coincide with the Kazhdan-Lusztig basis, as predicted
by J. Humphreys and V. Ostrik.
The proof is based on the results of [ABG ], [AB] and [B], which allow us to reduce the question to purity of IC sheaves on
affine flag varieties.
To the memory of my father 相似文献
19.
In the present paper, we introduce the concepts of Prüfer sheaves and adic sheaves over a weighted projective line of genus one or an elliptic curve, show that Prüfer sheaves and adic sheaves can characterize the category of coherent sheaves. Moreover, we describe the relationship between Prüfer sheaves and generic sheaves, and provide two methods to construct generic sheaves by using coherent sheaves and Prüfer sheaves. 相似文献
20.
Usha N. Bhosle 《Proceedings Mathematical Sciences》2005,115(4):445-451
LetM be the moduli space of generalized parabolic bundles (GPBs) of rankr and degree dona smooth curveX. LetM
−L
be the closure of its subset consisting of GPBs with fixed determinant− L. We define a moduli functor for whichM
−L
is the coarse moduli scheme. Using the correspondence between GPBs onX and torsion-free sheaves on a nodal curveY of whichX is a desingularization, we show thatM
−L
can be regarded as the compactified moduli scheme of vector bundles onY with fixed determinant. We get a natural scheme structure on the closure of the subset consisting of torsion-free sheaves
with a fixed determinant in the moduli space of torsion-free sheaves onY. The relation to Seshadri-Nagaraj conjecture is studied. 相似文献