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Related papers: Retraction of the bivariant Chern character

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We construct a groupoid equivariant Kasparov class for transversely oriented foliations in all codimensions. In codimension 1 we show that the Chern character of an associated semifinite spectral triple recovers the Connes-Moscovici cyclic…

K-Theory and Homology · Mathematics 2020-06-24 Lachlan MacDonald , Adam Rennie

We apply the concepts of superanalysis to present an intrinsically supersymmetric formulation of the Chern character in entire cyclic cohomology. We show that the cocycle condition is closely related to the invariance under…

High Energy Physics - Theory · Physics 2009-10-28 A. Lesniewski , K. Osterwalder

Following Bloch-Esnault-Kerz and Green-Griffiths' recent works on deformation of algebraic cycle classes, we use Chern character from K-theory to negative cyclic homology to show how to eliminate obstructions to deforming cycles.

Algebraic Geometry · Mathematics 2021-09-23 Sen Yang

This paper is the second part of a series of papers on noncommutative geometry and conformal geometry. In this paper, we compute explicitly the Connes-Chern character of an equivariant Dirac spectral triple. The formula that we obtain for…

Differential Geometry · Mathematics 2017-03-17 Raphael Ponge , Hang Wang

Products, multiplicative Chern characters, and finite coefficients, are unarguably among the most important tools in algebraic K-theory. Although they admit numerous different constructions, they are not yet fully understood at the…

K-Theory and Homology · Mathematics 2011-01-12 Goncalo Tabuada

We show a quantum version of Chern character homomorphism from the small quantum K-theory to the small quantum cohomology in the cases of projective spaces and incidence varieties, whose classical limit gives the classical Chern character…

Algebraic Geometry · Mathematics 2025-07-17 Hua-Zhong Ke , Changzheng Li , Jiayu Song

To each algebra over the complex numbers we associate a sequence of abelian groups in a contravariant functorial way. In degree (m-1) we have the m-summable Fredholm modules over the algebra modulo stable m-summable perturbations. These new…

K-Theory and Homology · Mathematics 2010-02-02 Jens Kaad

These notes form the next episode in a series of articles dedicated to a detailed proof of a cohomological index formula for transversally elliptic pseudo-differential operators and applications. The first two chapters are already available…

Differential Geometry · Mathematics 2008-01-21 Paul-Emile Paradan , Michèle Vergne

We analyze the relationship between Bott periodicity in topological $K$-theory and the natural periodicity of cyclic homology. This is a basis for understanding the multiplicativity, in odd dimensions, of a bivariant Chern-Connes character…

K-Theory and Homology · Mathematics 2022-07-29 Joachim Cuntz

There is a Chern character from K-theory to negative cyclic homology. We show that it preserves the decomposition coming from Adams operations, at least in characteristic 0. This is done by using infinitesimal cohomology to reduce to the…

K-Theory and Homology · Mathematics 2011-08-03 G. Cortiñas , C. Haesemeyer , C. A. Weibel

We show that the Chern-Connes character from Kasparov's bivariant K-theory to bivariant local cyclic cohomology is not always rationally injective. Counterexamples are provided by the reduced group $C^*$-algebras of word-hyperbolic groups…

K-Theory and Homology · Mathematics 2011-04-13 Michael Puschnigg

We prove the multiplicative property of localized Chern characters. As a direct consequence, a localized Chern character gives rise to a ring homomorphism from the K-group of periodic complexes to the bivariant Chow cohomology group. As an…

Algebraic Geometry · Mathematics 2025-04-22 Jeongseok Oh

In this paper, we construct for higher twists that arise from cohomotopy classes, the Chern character in higher twisted K-theory, that maps into higher twisted cohomology. We show that it gives rise to an isomorphism between higher twisted…

Differential Geometry · Mathematics 2021-06-23 Lachlan Macdonald , Varghese Mathai , Hemanth Saratchandran

We provide a formula for the Chern character of a holomorphic vector bundle in the hyper-cohomology of the de Rham complex of holomorphic sheaves on a complex manifold. This Chern character can be thought of as a completion of the Chern…

Algebraic Geometry · Mathematics 2025-04-11 Cheyne Glass , Thomas Tradler , Mahmoud Zeinalian

In this article we construct explicit cocycles in the Alexander-Spanier cohomological complex, representing the Chern character of an element in K-theory.

K-Theory and Homology · Mathematics 2007-05-23 Alexander Gorokhovsky

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

For an ample groupoid with torsion-free stabilizers, we construct a Chern character map going from the domain of the Baum-Connes assembly map of G to the groupoid homology groups of G with rational coefficients. As a main application,…

K-Theory and Homology · Mathematics 2025-09-10 Valerio Proietti , Makoto Yamashita

We study the "quantized calculus" corresponding to the algebraic ideas related to "twisted cyclic cohomology" introduced in [KMT]. With very similar definitions and techniques as those used in [jlo], we define and study "twisted entire…

Mathematical Physics · Physics 2007-05-23 Debashish Goswami

A generalization of Connes-Thom isomorphism is given for stable, homotopy invariant, and split exact functors on separable $C^*$-algebras. As examples of these functors, we concentrate on asymptotic and local cyclic cohomology and the…

K-Theory and Homology · Mathematics 2007-05-23 Vahid Shirbisheh

In this note we give a simple, model-independent construction of Chern classes as natural transformations from differential complex K-theory to differential integral cohomology. We verify the expected behaviour of these Chern classes with…

K-Theory and Homology · Mathematics 2009-07-16 Ulrich Bunke