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Related papers: Chern classes of splayed intersections

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In this work we study characteristic classes of possibly singular varieties embedded as a closed subvariety of a nonsingular variety. In special, we express the Schwartz-MacPherson class in terms of the $\mu$-class and Chern class of the…

Algebraic Geometry · Mathematics 2024-10-04 Antonio M. Ferreira , Fernando Lourenco

In this article, we investigate an axiomatic approach introduced by Grivaux for the study of rational Bott-Chern cohomology, and use it in that context to define Chern classes of coherent sheaves. This method also allows us to derive a…

Complex Variables · Mathematics 2022-10-13 Xiaojun Wu

We obtain a precise relation between the Chern-Schwartz-MacPherson class of a subvariety of projective space and the Euler characteristics of its general linear sections. In the case of a hypersurface, this leads to simple proofs of…

Algebraic Geometry · Mathematics 2013-07-04 Paolo Aluffi

We first construct closed spherical CR manifolds of dimension at least five having non-trivial first Chern class with real coefficients. We next prove a constraint on Chern classes with real coefficients of (not necessarily closed)…

Differential Geometry · Mathematics 2022-10-13 Yuya Takeuchi

In this paper, I construct noncompact analogs of the Chern classes of equivariant vector bundles over complex reductive groups. For the tangent bundle, these Chern classes yield an adjunction formula for the Euler characteristic of complete…

Algebraic Geometry · Mathematics 2007-05-23 Valentina Kiritchenko

We derive a formula for the Milnor class of scheme-theoretic global complete intersections (with arbitrary singularities) in a smooth variety in terms of the Segre class of its singular scheme. In codimension one the formula recovers a…

Algebraic Geometry · Mathematics 2013-11-19 James Fullwood

Let $X \subset Y$ be closed (possibly singular) subschemes of a smooth projective toric variety $T$. We show how to compute the Segre class $s(X,Y)$ as a class in the Chow group of $T$. Building on this, we give effective methods to compute…

Algebraic Geometry · Mathematics 2019-05-31 Corey Harris , Martin Helmer

I will present an explicit formula for the intersection indices of the Chern classes of an arbitrary reductive group with hypersurfaces. This formula has the following applications. First, it allows to compute explicitly the Euler…

Algebraic Geometry · Mathematics 2009-03-26 Valentina Kiritchenko

Since Chern and Grothendieck, Chern's characteristic class theory has made significant progress. In particular with regard to the classes of singular varieties. Conjectured by Grothendieck and Deligne and demonstrated by MacPherson, Chern…

Algebraic Geometry · Mathematics 2025-02-12 Jean-Paul Brasselet , Tadeusz Mostowski , Thuy Nguyen Thi Bich

The purpose of this short note is to prove a formula for the Chern-Mather classes of a toric variety in terms of its orbits and the local Euler obstructions at general points of each orbit (Theorem 2). We use the general definition of the…

Algebraic Geometry · Mathematics 2016-04-12 Ragni Piene

We prove a new formula for the Hirzebruch-Milnor classes of global complete intersections with arbitrary singularities describing the difference between the Hirzebruch classes and the virtual ones. This generalizes a formula for the…

Algebraic Geometry · Mathematics 2013-03-07 Laurentiu Maxim , Morihiko Saito , Joerg Schuermann

On a smooth variety, Serre's intersection formula computes intersection multiplicities via an alternating sum of the lengths of Tor groups. When the variety is singular, the corresponding sum can be a divergent series. But there are…

Commutative Algebra · Mathematics 2015-08-03 Daniel Erman

Let $K$ be an algebraically closed field of characteristic $0$. For $m\geq n$, we define $\tau_{m,n,k}$ to be the set of $m\times n$ matrices over $K$ with kernel dimension $\geq k$. This is a projective subvariety of $\bbP^{mn-1}$, and is…

Algebraic Geometry · Mathematics 2017-10-24 Xiping Zhang

The goal of the paper is two-fold. At first, we attempt to give a survey of some recent applications of symmetric polynomials and divided differences to intersection theory. We discuss: polynomials universally supported on degeneracy loci;…

alg-geom · Mathematics 2008-02-03 Piotr Pragacz

The goal of this paper is to study the Chern classes of coherent sheaves (and more generally perfect complexes) that admit crystal structures in the setting of crystalline cohomology and more generally relative prismatic cohomology. In the…

Algebraic Geometry · Mathematics 2023-10-03 Bhargav Bhatt

We introduce a notion of `proChow group' of varieties, agreeing with the notion of Chow group for complete varieties and covariantly functorial with respect to arbitrary morphisms. We construct a natural transformation from the functor of…

Algebraic Geometry · Mathematics 2012-04-11 Paolo Aluffi

Segre classes encode essential intersection-theoretic information concerning vector bundles and embeddings of schemes. In this paper we survey a range of applications of Segre classes to the definition and study of invariants of singular…

Algebraic Geometry · Mathematics 2025-04-02 Paolo Aluffi

We present two formulas for Chern classes of the tensor product of two vector bundles. In the first formula we consider a matrix containing Chern classes of the first bundle and we take a polynomial of this matrix with Chern classes of the…

Algebraic Topology · Mathematics 2019-10-01 Zsolt Szilágyi

We define the equivariant Chern-Schwartz-MacPherson class of a possibly singular algebraic variety with a group action over the complex number field (or a field of characteristic 0). In fact, we construct a natural transformation from the…

Algebraic Geometry · Mathematics 2009-11-10 Toru Ohmoto

General expressions are given for Chern forms up to the 13th order in curvature in terms of simple polynomial concomitants of the curvature 2-form for n-dimensional differentiable manifolds having a general linear connection.

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. C. Briggs