English
Related papers

Related papers: Orbifold index and equivariant K-homology

200 papers

In this article, we start to recall the inversion formula for the convolution with the Box spline. The equivariant cohomology and the equivariant K-theory with respect to a compact torus G of various spaces associated to a linear action of…

Differential Geometry · Mathematics 2015-03-17 C. De Concini , C. Procesi , M. Vergne

This note surveys the well-known structure of G-manifolds and summarizes parts of two papers that have not yet appeared in print: one with joint with J. Bruning and F. W. Kamber, and another with I. Prokhorenkov. In particular, from a given…

Differential Geometry · Mathematics 2009-09-01 Ken Richardson

We construct a regularized index of a generalized Dirac operator on a complete Riemannian manifold endowed with a proper action of a unimodular Lie group. We show that the index is preserved by a certain class of non-compact cobordisms and…

Differential Geometry · Mathematics 2015-12-09 Maxim Braverman

Let $G$ be a connected, linear real reductive group. We give sufficient conditions ensuring the well-definedness of the delocalized eta invariant $\eta_g (D_X)$ associated to a Dirac operator $D_X$ on a cocompact $G$-proper manifold $X$ and…

Differential Geometry · Mathematics 2023-07-20 Paolo Piazza , Hessel Posthuma , Yanli Song , Xiang Tang

We prove a {\Gamma}-equivariant version of the algebraic index theorem, where {\Gamma} is a discrete group of automorphisms of a formal deformation of a symplectic manifold. The particular cases of this result are the algebraic version of…

K-Theory and Homology · Mathematics 2021-07-01 Alexander Gorokhovsky , Niek de Kleijn , Ryszard Nest

Given an elliptic action of a compact Lie group $G$ on a co-oriented contact manifold $(M,E)$ one obtains two naturally associated objects: A $G$-transversally elliptic operator $\dirac$, and an equivariant differential form with…

Differential Geometry · Mathematics 2008-06-23 Sean Fitzpatrick

We show that, for each symmetry class based on the tenfold way classification, the effective Dirac operator obtained by integrating out the additional bulk direction takes a value in the corresponding classifying space, from which we obtain…

High Energy Physics - Theory · Physics 2023-09-22 Taro Kimura , Masataka Watanabe

This paper computes the Dirac cohomology $H_D(\pi)$ of irreducible unitary Harish-Chandra modules $\pi$ of complex classical groups viewed as real reductive groups. More precisely, unitary representations with nonzero Dirac cohomology are…

Representation Theory · Mathematics 2022-03-31 Dan Barbasch , Chao-Ping Dong , Kayue Daniel Wong

We construct a Baum-Douglas type model for $K$-homology with coefficients in $\mathbb{Z}/k\mathbb{Z}$. The basic geometric object in a cycle is a $spin^c$ $\mathbb{Z}/k\mathbb{Z}$-manifold. The relationship between these cycles and the…

K-Theory and Homology · Mathematics 2011-10-20 Robin J. Deeley

We compute $K$-theory invariants of algebras of pseudodifferential operators on manifolds with corners and prove an equivariant index theorem for operators invariant with respect to an action of $\R^k.$ We discuss the relation between our…

funct-an · Mathematics 2008-02-03 Richard B. Melrose , Victor Nistor

Using the Arthur-Selberg trace formula we express the index of a Dirac operator on an arithmetic quotient over a totally real field with at least two real embeddings as the integral over the index form plus a sum of orbital integrals. For…

dg-ga · Mathematics 2008-02-03 Anton Deitmar

Consider a proper, isometric action by a unimodular locally compact group $G$ on a Riemannian manifold $M$ with boundary, such that $M/G$ is compact. For an equivariant, elliptic operator $D$ on $M$, and an element $g \in G$, we define a…

Differential Geometry · Mathematics 2021-10-26 Peter Hochs , Bai-Ling Wang , Hang Wang

The smooth hermitian representations of a split reductive p-adic group whose restriction to a maximal hyperspecial compact subgroup contain a single K-type with Iwahori fixed vectors have been studied in [D. Barbasch, A. Moy, Classification…

Representation Theory · Mathematics 2012-08-24 Dan Ciubotaru , Allen Moy

We give a construction of a Dirac operator on a quantum group based on any simple Lie algebra of classical type. The Dirac operator is an element in the vector space $U_q(\g) \otimes \mathrm{cl}_q(\g)$ where the second tensor factor is a…

Quantum Algebra · Mathematics 2015-05-20 Antti J. Harju

We calculate the equivariant index formula for an infinite dimensional Clifford module canonically associated to any Riemannian manifold. It encompasses the fractional index formula of the projective Dirac operator by…

K-Theory and Homology · Mathematics 2011-07-18 Makoto Yamashita

Let M be a foliated manifold and G a discrete group acting on M by diffeomorphisms mapping leaves to leaves. Then G naturally acts by automorphisms on the algebra of Heisenberg pseudodifferential operators on the foliation. Our main result…

K-Theory and Homology · Mathematics 2016-12-09 Denis Perrot , Rudy Rodsphon

We prove an index formula for the Dirac operator acting on two-valued spinors on a $3$-manifold $M$ which branch along a smoothly embedded graph $\Sigma \subset M$, and with respect to a boundary condition along $\Sigma$ inspired by an…

Differential Geometry · Mathematics 2025-12-04 Andriy Haydys , Rafe Mazzeo , Ryosuke Takahashi

Suppose that $(M,E)$ is a compact contact manifold, and that a compact Lie group $G$ acts on $M$ transverse to the contact distribution $E$. In an earlier paper, we defined a $G$-transversally elliptic Dirac operator $\dirac$, constructed…

Symplectic Geometry · Mathematics 2012-01-17 Sean Fitzpatrick

The Chern classes of a K-theory class which is represented by a vector bundle with connection admit refinements to Cheeger-Simons classes in Deligne cohomology. In the present paper we consider similar refinements in the case where the…

Differential Geometry · Mathematics 2007-05-23 U. Bunke

This is an expository paper which gives a proof of the Atiyah-Singer index theorem for Dirac operators, presenting the theorem as a computation of the K-homology of a point. This paper and its follow up ("K-homology and index theory II:…

Differential Geometry · Mathematics 2016-04-13 Paul Baum , Erik van Erp