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Related papers: Local Index Theory over Etale Groupoids

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We pursue the study of local index theory for operators of Fourier-integral type associated to non-proper and non-isometric actions of Lie groupoids, initiated in a previous work. We introduce the notion of geometric cocycles for Lie…

K-Theory and Homology · Mathematics 2016-12-14 Denis Perrot

We present an index theorem for certain hypoelliptic differential operators on foliated manifolds. Our proof is a development of Alain Connes tangent groupoid proof of the Atiyah-Singer index theorem. The paper is largely self-contained.

Differential Geometry · Mathematics 2010-02-24 Erik van Erp

Given a gerbe $L$, on the holonomy groupoid $\mathcal G$ of the foliation $(M, \mathcal F)$, whose pull-back to $M$ is torsion, we construct a Connes $\Phi$-map from the twisted Dupont-Sullivan bicomplex of $\mathcal G$ to the cyclic…

K-Theory and Homology · Mathematics 2017-03-03 Moulay-Tahar Benameur , Alexander Gorokhovsky , Eric Leichtnam

We give applications of the higher Lefschetz theorems for foliations of [BH10], primarily involving Haefliger cohomology. These results show that the transverse structures of foliations carry important topological and geometric information.…

Differential Geometry · Mathematics 2024-03-01 Moulay Tahar Benameur , James L. Heitsch

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

Many index theorems (both classical and in noncommutative geometry) can be interpreted in terms of a Lie groupoid acting properly on a manifold and leaving an elliptic family of pseudodifferential operators invariant. Alain Connes in his…

Operator Algebras · Mathematics 2007-05-23 Alan L. T. Paterson

Many index theorems (both classical and in noncommutative geometry) can be interpreted in terms of a Lie groupoid acting properly on a manifold and leaving an elliptic family of pseudodifferential operators invariant. Alain Connes in his…

Operator Algebras · Mathematics 2007-05-23 Alan L. T. Paterson

In this note, we explain how to prove several basic results about finite index extensions of irreducible local M\"obius covariant nets in the setting of Connes fusion.

Operator Algebras · Mathematics 2025-07-21 Bin Gui

Given a proper, cocompact action of a Lie groupoid, we define a higher index pairing between invariant elliptic differential operators and smooth groupoid cohomology classes. We prove a cohomological index formula for this pairing by…

Differential Geometry · Mathematics 2014-06-06 M. J. Pflaum , H. Posthuma , X. Tang

We study index theory on homogeneous spaces associated to an almost connected Lie group in terms of the topological aspect and the analytic aspect. On the topological aspect, we obtain a topological formula as a result of the Riemann-Roch…

Differential Geometry · Mathematics 2024-01-17 Hang Wang , Zijing Wang

Let $M$ be a $n$-dimensional complex manifold and $f,g:M\to M$ two distinct holomorphic self-maps. Suppose that $f$ and $g$ coincide on a globally irreducible compact hypersurface $S\subset M$. We show that if one of the two maps is a local…

Complex Variables · Mathematics 2016-04-11 Paolo Arcangeli

In this paper we consider a family of Dirac-type operators on fibration $P \to B$ equivariant with respect to an action of an etale groupoid. Such a family defines an element in the bivariant $K$ theory. We compute the action of the…

Differential Geometry · Mathematics 2007-05-23 Alexander Gorokhovsky

The notion of local subgroupoid as a generalisation of a local equivalence relation was defined in a previous paper by the first two authors. Here we use the notion of star path connectivity for a Lie groupoid to give an important new class…

Differential Geometry · Mathematics 2007-05-23 R. Brown , I. Icen , O. Mucuk

We consider singular foliations whose holonomy groupoid may be nicely decomposed using Lie groupoids (of unequal dimension). We show that the Baum-Connes conjecture can be formulated in this setting. This conjecture is shown to hold under…

K-Theory and Homology · Mathematics 2020-01-15 Iakovos Androulidakis , Georges Skandalis

We construct the holonomy groupoid of any singular foliation. In the regular case this groupoid coincides with the usual holonomy groupoid of Winkelnkemper (1983); the same holds in the singular cases of Bigonnet and Pradines (1985) and…

Differential Geometry · Mathematics 2009-09-23 Iakovos Androulidakis , Georges Skandalis

Main theorem of this paper states that Floer cohomology groups in a Hilbert space are isomorphic to the cohomological Conley Index. It is also shown that calculating cohomological Conley Index does not require finite dimensional…

Differential Geometry · Mathematics 2014-08-05 Maciej Starostka

We develop a local index theory for Fourier-integral operators associated to non-proper and non-isometric actions of Lie groupoids on smooth submersions. To such action is associated a short exact sequence of algebras, relating genuine…

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

Etale groupoids arise naturally as models for leaf spaces of foliations, for orbifolds, and for orbit spaces of discrete group actions. In this paper we introduce a sheaf homology theory for etale groupoids. We prove its invariance under…

K-Theory and Homology · Mathematics 2007-05-23 Marius Crainic , Ieke Moerdijk

For a proper, cocompact action by a locally compact group of the form $H \times G$, with $H$ compact, we define an $H \times G$-equivariant index of $H$-transversally elliptic operators, which takes values in $KK_*(C^*H, C^*G)$. This…

K-Theory and Homology · Mathematics 2020-06-24 Peter Hochs , Hang Wang

We give a "conceptual" approach to Kourganoff's results about foliations with a transverse similarity structure. In particular, we give a proof, understandable by the targeted community, of the very important result classifying the holonomy…

Differential Geometry · Mathematics 2025-06-24 Brice Flamencourt , Abdelghani Zeghib
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