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Related papers: On the 1-homotopy type of Lie groupoids

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An arbitrary Lie groupoid gives rise to a groupoid of germs of local diffeomorphisms over its base manifold, known as its effect. The effect of any bundle of Lie groups is trivial. All quotients of a given Lie groupoid determine the same…

Category Theory · Mathematics 2015-08-04 Giorgio Trentinaglia

We introduce multiplicative differential forms on Lie groupoids with values in VB-groupoids. Our main result gives a complete description of these objects in terms of infinitesimal data. By considering split VB-groupoids, we are able to…

Differential Geometry · Mathematics 2021-09-15 Thiago Drummond , Leandro Egea

In this article we develop a unified framework for proving Morita invariance of cohomology theories associated to Lie groupoids. Our approach is to view these cohomology theories as arising from sheaves of modules on the nerve of the…

Differential Geometry · Mathematics 2025-09-10 Xiang Tang , Joel Villatoro

In this paper we study the Lie groupoids which appear in foliation theory. A foliation groupoid is a Lie groupoid which integrates a foliation, or, equivalently, whose anchor map is injective. The first theorem shows that, for a Lie…

K-Theory and Homology · Mathematics 2007-05-23 M. Crainic , I. Moerdijk

Using Morita type stratifications, we establish a one-to-one correspondence between geometric vector fields on a separated differentiable stack and stratified vector fields on its orbit space. This correspondence enables us to derive a…

Differential Geometry · Mathematics 2026-05-06 Mateus de Melo , Juan Sebastian Herrera-Carmona , Fabricio Valencia

We study the behavior of the modular class of a Lie algebroid under general Lie algebroid morphisms by introducing the relative modular class. We investigate the modular classes of pull-back morphisms and of base-preserving morphisms…

Differential Geometry · Mathematics 2008-04-18 Yvette Kosmann-Schwarzbach , Camille Laurent-Gengoux , Alan Weinstein

As a higher dimensional version of the theory of Morse functions, there have been various studies of smooth manifolds using generic smooth maps. As fundamental results, in these studies, they have found that inverse images of such maps…

Algebraic Topology · Mathematics 2018-12-21 Naoki Kitazawa

In this paper, we show that there is a close relationship between generalized subtangent manifolds and Lie groupoids. We obtain equivalent assertions among the integrability conditions of generalized almost subtangent manifolds, the…

Geometric Topology · Mathematics 2012-11-02 Fulya Sahin

In this article we study the normal bundle and the deformation to the normal cone functors to get deformation Lie groupoids that allow us to construct pushforward maps in any suitable (co)homology theory for Lie groupoids (not only…

K-Theory and Homology · Mathematics 2026-05-06 Paulo Carrillo Rouse , Quentin Karegar Baneh Kohal

We show that the complete bornological convolution algebras of Lie groupoids and convolution bimodules of groupoid bibundles define a monoidal functor from the 2-category of differentiable stacks to the Morita 2-category of complete…

Differential Geometry · Mathematics 2026-05-29 David Aretz , Christian Blohmann

We introduce Morita equivalence for Nijenhuis groupoids and for their infinitesimal counterparts, establishing a global-to-infinitesimal correspondence under the Lie functor. A special case is that of holomorphic Lie groupoids and…

Differential Geometry · Mathematics 2026-04-10 Andrés I. Rodríguez

For any topological groupoid G and any homomorphism from a locally compact Hausdorff topological group K to G, we construct an associated monodromy group. We prove that Morita equivalent topological groupoids have the same monodromy groups.…

Differential Geometry · Mathematics 2018-03-22 Janez Mrcun

We generalize the van Est map and isomorphism theorem in three ways, and we discuss conjectured connections with homotopy theory, including a proposal of a category which unifies differentiable stacks, Lie algebroids and homotopy theory. In…

Differential Geometry · Mathematics 2022-05-13 Joshua Lackman

We present a way of constructing and deforming diffeomorphisms of manifolds endowed with a Lie group action. This is applied to the study of exotic diffeomorphisms and involutions of spheres and to the equivariant homotopy of Lie groups.

Differential Geometry · Mathematics 2007-08-14 C. E. Durán , A. Rigas

We develop a theory of $\times$-homotopy, fundamental groupoids and covering spaces that apply to non-simple graphs, generalizing existing results for simple graphs. We prove that $\times$-homotopies from finite graphs can be decomposed…

Combinatorics · Mathematics 2026-03-17 Tien Chih , Laura Scull

A topological groupoid G is K-pointed, if it is equipped with a homomorphism from a topological group K to G. We describe the homotopy groups of such K-pointed topological groupoids and relate these groups to the ordinary homotopy groups in…

Differential Geometry · Mathematics 2017-03-17 B. Jelenc , J. Mrcun

This paper identifies the homotopy theories of topological stacks and orbispaces with unstable global homotopy theory. At the same time, we provide a new perspective by interpreting it as the homotopy theory of `spaces with an action of the…

Algebraic Topology · Mathematics 2020-01-13 Stefan Schwede

Some sorts of generalized morphisms are defined from very basic mathematical objects such as sets, functions, and partial functions. A wide range of mathematical notions such as continuous functions between topological spaces, ring…

Rings and Algebras · Mathematics 2024-07-24 Gang Hu

The notion of local equivalence relation on a topological space is generalised to that of local subgroupoid. The main result is the construction of the holonomy and monodromy groupoids of certain Lie local subgroupoids, and the formulation…

Differential Geometry · Mathematics 2007-05-23 Ronald Brown , Ilhan Içen

We describe the relation of $r$-similarity and finite-order invariants on the homotopy set $[S^1,Y]=\pi_1(Y)$.

Algebraic Topology · Mathematics 2026-02-16 S. S. Podkorytov