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Related papers: Pro-Chern-Schwartz-MacPherson class for DM stacks

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We give a new formula for the Chern-Schwartz-MacPherson class of a hypersurface in a nonsigular compact complex analytic variety. In particular this formula generalizes our previous result on the Euler characteristic of such a hypersurface.…

Algebraic Geometry · Mathematics 2007-05-23 Adam Parusinski , Piotr Pragacz

Paolo Aluffi showed that the Chern--Schwartz--MacPherson class of the complement of a free arrangement agrees with the total Chern class of the sheaf of logarithmic derivations along the arrangement. We describe the defect of equality of…

Algebraic Geometry · Mathematics 2014-09-18 Ngoc Anh Pham

Let $V$ be a possibly singular scheme-theoretic complete intersection subscheme of $\mathbb{P}^n$ over an algebraically closed field of characteristic zero. Using a recent result of Fullwood ("On Milnor classes via invariants of singular…

Algebraic Geometry · Mathematics 2017-11-15 Martin Helmer

For a large class of possibly singular complete intersections we prove a formula for their Chern-Schwartz-MacPherson classes in terms of a single blowup along a scheme supported on the singular loci of such varieties. In the hypersurface…

Algebraic Geometry · Mathematics 2016-04-28 James Fullwood , Dongxu Wang

We define the notion of a trace kernel on a manifold M. Roughly speaking, it is a sheaf on M x M for which the formalism of Hochschild homology applies. We associate a microlocal Euler class to such a kernel, a cohomology class with values…

Algebraic Geometry · Mathematics 2014-06-04 Masaki Kashiwara , Pierre Schapira

We construct a functor, from the category of schemes to the category of graded rings, that is an initial object for having a theory of Chern classes with an additive first Chern class. For any scheme $X$, the graded ring that our functor…

Algebraic Geometry · Mathematics 2020-06-29 Eoin Mackall

Let $V$ be a closed subscheme of a projective space $\mathbb{P}^n$. We give an algorithm to compute the Chern-Schwartz-MacPherson class, Euler characteristic and Segre class of $ V$. The algorithm can be implemented using either symbolic or…

Algebraic Geometry · Mathematics 2016-03-24 Martin Helmer

We compute the equivariant cohomology of complex projective spaces associated to finite-dimensional representations of $C_2$, using ordinary cohomology graded on representations of the fundamental groupoid, with coefficients in the Burnside…

Algebraic Topology · Mathematics 2022-05-17 Steven R. Costenoble , Thomas Hudson , Sean Tilson

The Chern-Schwartz-MacPherson (CSM) and motivic Chern (mC) classes of Schubert cells in a Grassmannian are one parameter deformations of the fundamental classes of the Schubert varieties in cohomology and K-theory respectively. Like the…

Algebraic Geometry · Mathematics 2020-11-03 Yiyan Shou

We prove that one may approximate parametric suprema of constructible and power-constructible functions using functions within the same class. This resolves a conjecture by Adiceam and Cluckers, which was posited after studying a question…

Algebraic Geometry · Mathematics 2026-05-05 Tijs Buggenhout , Mathias Stout , Lisa Vandebrouck

For a possibly singular complex variety $X$, generating functions of total "orbifold Chern homology classes" of symmetric products $S^nX$ are given. Those are very natural "Chern class versions" (in the sense of Schwartz-MacPherson) of…

Algebraic Geometry · Mathematics 2010-04-01 Toru Ohmoto

A formula for the structure constants of the multiplication of Schubert classes is obtained in arXiv:1909.05283. In this note, we prove analogous formulae for the Chern--Schwartz--MacPherson (CSM) classes and Segre--Schwartz--MacPherson…

Algebraic Geometry · Mathematics 2019-10-01 Changjian Su

By resolving an arbitrary perfect derived object over a Deligne-Mumford stack, we define its Euler class. We then apply it to define the Euler numbers for a smooth Calabi-Yau threefold in the 4-dimensional projective space. These numbers…

Algebraic Geometry · Mathematics 2010-10-07 Yi Hu , Jun Li

We introduce the notion of Chern-Simons classes for curved DG-pairs and we prove that a particular case of this general construction provides canonical $L_\infty$ liftings of Buchweitz-Flenner semiregularity maps for coherent sheaves on…

Algebraic Geometry · Mathematics 2023-09-07 Ruggero Bandiera , Emma Lepri , Marco Manetti

We give an explicit description of toric sheaves on the weighted projective plane $\mathbb{P}(a,b,c)$ viewed as a toric Deligne-Mumford stack. The integers $(a,b,c)$ are not necessarily chosen coprime or mutually coprime allowing for gerbe…

Algebraic Geometry · Mathematics 2019-02-07 Amin Gholampour , Yunfeng Jiang , Martijn Kool

The goal of this work is to construct integral Chern classes and higher cycle classes for a smooth variety over a perfect field of characteristic p>0 that are compatible with the rigid Chern classes defined by Petrequin. The Chern classes…

Number Theory · Mathematics 2014-06-17 Veronika Ertl

Given a collection of test functions, one defines the associated Schur-Agler class as the intersection of the contractive multipliers over the collection of all positive kernels for which each test function is a contractive multiplier. We…

Functional Analysis · Mathematics 2011-09-20 Joseph A. Ball , Moisés Guerra Huamán

In this paper, we construct proper pushforwards and flat pullbacks in Chow groups of coherent sheaf stacks over a Deligne-Mumford(DM) stack. When there is a relative semi-perfect obstruction theory for a DM-type morphism $X \to Y$, $X$ is a…

Algebraic Geometry · Mathematics 2019-09-12 Sanghyeon Lee

We give a general formula for the defect appearing in the Verdier-type Riemann-Roch formula for Chern-Schwartz-MacPherson classes in the case of a regular embedding. Our proof of this formula uses the constructible function version of…

Algebraic Geometry · Mathematics 2007-05-23 Joerg Schuermann

Donaldson-Thomas invariant is expressed as the weighted Euler characteristic of the so-called Behrend (constructible) function. In \cite{Behrend} Behrend introduced a DT-type invariant for a morphism. Motivated by this invariant, we extend…

Algebraic Geometry · Mathematics 2015-12-21 Vittoria Bussi , Shoji Yokura