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Related papers: On Chern classes of almost representations

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We apply the machinery of relative tensor triangular Chow groups to the action of the derived category of quasi-coherent sheaves on a noetherian scheme $X$ on the derived category of quasi-coherent $\mathcal{A}$-modules, where $\mathcal{A}$…

Algebraic Geometry · Mathematics 2019-02-05 Pieter Belmans , Sebastian Klein

Let G be a simple linear algebraic group defined over the complex numbers. Fix a proper parabolic subgroup P of G and a nontrivial antidominant character \chi of P. We prove that a holomorphic principal G-bundle E over a connected complex…

Algebraic Geometry · Mathematics 2008-09-01 Indranil Biswas , Ugo Bruzzo

In the 80's, Quillen constructed a de Rham relative cohomology class associated to a smooth morphism between vector bundles, that we call the relative Quillen Chern character. In the first part of this paper we prove the multiplicativ…

Differential Geometry · Mathematics 2008-09-26 Paul-Emile Paradan , Michèle Vergne

The mod-p cohomology ring of the extraspecial p-group of exponent p is studied for odd p. We investigate the subquotient ch(G) generated by Chern classes modulo the nilradical. The subring of ch(G) generated by Chern classes of…

Group Theory · Mathematics 2015-02-23 David J Green , Ian J Leary

The Chern character of a complex vector bundle is most conveniently defined as the exponential of a curvature of a connection. It is well known that its cohomology class does not depend on the particular connection chosen. It has been shown…

Differential Geometry · Mathematics 2007-05-23 Dmitry Gerenrot

Given a smooth action of a Lie group on a manifold, we give two constructions of the Chern character of an equivariant vector bundle in the cyclic cohomology of the crossed product algebra. The first construction associates a cycle to the…

Differential Geometry · Mathematics 2023-04-10 Bjarne Kosmeijer , Hessel Posthuma

We show that the K-groups K_{n}(O) for O the integers or an order in a CM field and n>0 appear as direct summands of the homotopy groups of various localisations of Zakharevich's K-theory space. After rationalisation and going to the…

K-Theory and Homology · Mathematics 2021-09-03 Oliver Braunling , Michael Groechenig

Given a parabolic vector bundle, we construct for it a projectivization and tautological line bundle. These are analogs of the projectivization and tautological line bundle for an usual vector bundle. Using these we give a construction of…

Algebraic Geometry · Mathematics 2012-09-17 Indranil Biswas , Ajneet Dhillon

We describe the integral equivariant cohomology ring of a weighted projective space in terms of piecewise polynomials, and thence by generators and relations. We deduce that the ring is a perfect invariant, and prove a Chern class formula…

Algebraic Topology · Mathematics 2009-04-15 Anthony Bahri , Matthias Franz , Nigel Ray

We enumerate complex rank $n$ topological vector bundles on $\mathbb CP^{n+1}$ with prescribed Chern classes. This extends work of Atiyah and Rees in the case $n=2$ and work of Hu in the case that all Chern classes are zero.

Algebraic Topology · Mathematics 2026-03-03 Morgan P. Opie

We study the cohomological classification of vector bundles on smooth real affine surfaces and threefolds. We show that, as was observed in joint work in A. Asok and J. Fasel and in a coming joint paper with S. Banerjee and J. Fasel, under…

Algebraic Geometry · Mathematics 2026-05-22 Samuel Lerbet

We discuss conjectures following from the attractor mechanism in type II string theory about the possible Chern classes of stable holomorphic vector bundles on Calabi-Yau threefolds. In particular, we give sufficient conditions for Chern…

Algebraic Geometry · Mathematics 2007-05-23 Michael R. Douglas , Rene Reinbacher , Shing-Tung Yau

This paper is Part III of a series of three. We begin by introducing the notion of $h$-special varieties, which can be seen as varieties "chain-connected by the Zariski closures of entire curves." We prove that if $X$ is either a special…

Algebraic Geometry · Mathematics 2025-12-24 Benoit Cadorel , Ya Deng , Katsutoshi Yamanoi

We compute the Chern-Simons transgressed forms of some modularly invariant characteristic forms, which are related to the elliptic genera. We study the modularity properties of these secondary characteristic forms and the relations among…

Differential Geometry · Mathematics 2007-12-08 Qingtao Chen , Fei Han

We study singular hermitian metrics on holomorphic vector bundles, following Berndtsson-P{\u{a}}un. Previous work by Raufi has shown that for such metrics, it is in general not possible to define the curvature as a current with measure…

Complex Variables · Mathematics 2018-01-16 Richard Lärkäng , Hossein Raufi , Jean Ruppenthal , Martin Sera

We study the homotopy aspects of the twisted Chern classes of torsion bundle gerbe modules. Using Sullivan's rational homotopy theory, we realize the twisted Chern classes at the level of classifying spaces. The construction suggests a…

Algebraic Topology · Mathematics 2022-03-29 Fei Han , Ruizhi Huang , Varghese Mathai

Given a flexible $n$-gon with generic side lengths, the moduli space of its configurations in $\mathbb{R}^2$ as well as in $\mathbb{R}^3$ is a smooth manifold. It is equipped with $n$ \textit{tautological} line bundles whose definition is…

Geometric Topology · Mathematics 2017-12-06 Ilia Nekrasov , Gaiane Panina , Alena Zhukova

We show that every bad orbifold vector bundle can be realized as the restriction of a good orbifold vector bundle to a suborbifold of the base space. We give an explicit construction of this result in which the Chen-Ruan orbifold cohomology…

Differential Geometry · Mathematics 2008-06-09 Christopher Seaton

In this paper, we prove a generalization of Reznikov's theorem which says that the Chern-Simons classes and in particular the Deligne Chern classes (in degrees $>1$) are torsion, of a flat bundle on a smooth complex projective variety. We…

Algebraic Geometry · Mathematics 2007-07-04 Jaya N. Iyer , Carlos T. Simpson

We construct a model of differential K-theory, using the geometrically defined Chern forms, whose cocycles are certain equivalence classes of maps into the Grassmannians and unitary groups. In particular, we produce the circle-integration…

K-Theory and Homology · Mathematics 2015-07-08 Thomas Tradler , Scott O. Wilson , Mahmoud Zeinalian