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Related papers: Orbifold index and equivariant K-homology

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In this expository paper, we explain a formula for the multiplicities of the index of an equivariant transversally elliptic operator on a $G$-manifold. The formula is a sum of integrals over blowups of the strata of the group action and…

Differential Geometry · Mathematics 2021-01-28 Jochen Brüning , Franz W. Kamber , Ken Richardson

An integer valued topological index of a Dirac operator is introduced for a pair of a 4n+2 dimensional open Spin^c manifold and a section of the determinant line bundle satisfying some property. We show a relation between the index and an…

Differential Geometry · Mathematics 2014-01-22 Shin Hayashi

In this article, we survey the recent constructions of cyclic cocycles on the Harish-Chandra Schwartz algebra of a connected real reductive Lie group $G$ and their applications to higher index theory for proper cocompact $G$-actions.

K-Theory and Homology · Mathematics 2023-09-07 Paolo Piazza , Xiang Tang

Equivariant indices have previously been defined in cases where either the group or the orbit space in question is compact. In this paper, we develop an equivariant index without assuming the group or the orbit space to be compact. This…

K-Theory and Homology · Mathematics 2016-09-06 Peter Hochs , Yanli Song

Recently, two of the authors of this paper constructed cyclic cocycles on Harish-Chandra's Schwartz algebra of linear reductive Lie groups that detect all information in the $K$-theory of the corresponding group $C^*$-algebra. The main…

Differential Geometry · Mathematics 2021-06-30 Peter Hochs , Yanli Song , Xiang Tang

In this paper, we employ the framework of localization algebras to compute the equivariant K-homology class of the Euler characteristic operator, a central object in studying equivariant index theory on manifolds. This approach provides a…

Algebraic Topology · Mathematics 2024-10-22 Hongzhi Liu , Hang Wang , Zijing Wang , Shaocong Xiang

For a smooth manifold X of dimension <d we construct a homomorphism from the algebraic K-theory group in degree d of the algebra of smooth functions on X to the degree -d-1 topological K-theory of X with coefficients in C/Z. This map…

K-Theory and Homology · Mathematics 2014-12-09 Ulrich Bunke

Extending ideas of twisted equivariant $K$-theory, we construct twisted versions of the representation rings for Lie superalgebras and Lie supergroups, built from projective $\Z_{2}$-graded representations with a given cocycle. We then…

Representation Theory · Mathematics 2007-05-23 Gregory D. Landweber

We introduce and study the index morphism for G-invariant leafwise G-transversally elliptic operators on smooth closed foliated manifolds which are endowed with leafwise actions of the compact group G. We prove the usual axioms of excision,…

K-Theory and Homology · Mathematics 2021-03-17 Alexandre Baldare , Moulay-Tahar Benameur

We present an equivariant generalization of Boutet de Monvel's index theorem for Toeplitz operators on contact manifolds. We prove that the Dirac operator and the Szeg\"o projection determine the same class in equivariant $K$-homology,…

K-Theory and Homology · Mathematics 2026-04-20 Alexander Gorokhovsky , Erik van Erp

We generalize Roe's index theorem for graded generalized Dirac operators on amenable manifolds to multigraded elliptic uniform pseudodifferential operators. This generalization will follow as a corollary from a local index theorem that is…

Differential Geometry · Mathematics 2018-10-03 Alexander Engel

We first introduce an invariant index for G-equivariant elliptic differential operators on a locally compact manifold M admitting a proper cocompact action of a locally compact group G. It generalizes the Kawasaki index for orbifolds to the…

Differential Geometry · Mathematics 2014-11-18 Varghese Mathai , Weiping Zhang

For the q-deformation G_q, 0<q<1, of any simply connected simple compact Lie group G we construct an equivariant spectral triple which is an isospectral deformation of that defined by the Dirac operator D on G. Our quantum Dirac operator…

Operator Algebras · Mathematics 2007-05-23 Sergey Neshveyev , Lars Tuset

Real and complex Clifford bundles and Dirac operators defined on them are considered. By using the index theorems of Dirac operators, table of topological invariants is constructed from the Clifford chessboard. Through the relations between…

Mathematical Physics · Physics 2017-10-20 Ümit Ertem

Using the Witten deformation and localization algebra techniques, we compute the $G$-equivariant $K$-homology class of the de Rham operator on a proper cocompact $G$-spin manifold, where $G$ is an almost connected Lie group. By applying a…

Operator Algebras · Mathematics 2025-08-22 Hongzhi Liu , Hang Wang , Zijing Wang , Shaocong Xiang

We generalize Roe's Index Theorem for operators of Dirac type on open manifolds to elliptic pseudodifferential operators. To this end we introduce a class of pseudodifferential operators on manifolds of bounded geometry which is more…

Differential Geometry · Mathematics 2014-10-30 Alexander Engel

We develop elliptic theory of operators associated with a diffeomorphism of a closed smooth manifold. The aim of the present paper is to obtain an index formula for such operators in terms of topological invariants of the manifold and of…

Operator Algebras · Mathematics 2015-11-06 Anton Savin , Boris Sternin

Using the unbounded picture of analytical K-homology, we associate a well-defined K-homology class to an unbounded symmetric operator satisfying certain mild technical conditions. We also establish an ``addition formula'' for the Dirac…

K-Theory and Homology · Mathematics 2007-05-23 Hela Bettaieb , Michel Matthey , Alain Valette

In this paper, we give a geometric expression for the multiplicities of the equivariant index of a spin-c Dirac operator.

Differential Geometry · Mathematics 2015-12-23 Paul-Emile Paradan , Michele Vergne

We study boundary conditions for elliptic operators on non-compact manifolds with boundary via uniform K-homology, a version of K-homology sensitive to the large-scale geometry of the manifold. To that end, we develop the theory of relative…

K-Theory and Homology · Mathematics 2026-03-02 Matti Lyko