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Related papers: Basic sections of LA-groupoids

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Motivated by the computations done in \cite{C1}, where I introduced and discussed what I called the groupoid of generalized gauge transformations, viewed as a groupoid over the objects of the category $\mathsf{Bun}_{G,M}$ of principal…

Differential Geometry · Mathematics 2007-05-23 C. A. Rossi

By a ring groupoid we mean an animated ring whose i-th homotopy groups are zero for all i>1. In this expository note we give an elementary treatment of the (2,1)-category of ring groupoids (i.e., without referring to general animated rings…

Category Theory · Mathematics 2021-04-16 Vladimir Drinfeld

We show that the leaves of an LA-groupoid which pass through the unit manifold are, modulo a connectedness issue, Lie groupoids. We illustrate this phenomenon by considering the cotangent Lie algebroids of Poisson groupoids thus obtaining…

Symplectic Geometry · Mathematics 2020-06-18 Daniel Álvarez

We consider actions of non-compact simple Lie groups preserving an analytic rigid geometric structure of algebraic type on a compact manifold. The structure is not assumed to be unimodular, so an invariant measure may not exist. Ergodic…

Dynamical Systems · Mathematics 2009-01-06 Amos Nevo , Robert J. Zimmer

We extend some fundamental definitions and constructions in the established generalisation of Lie theory involving Lie groupoids by reformulating them in terms of groupoids internal to a well-adapted model of synthetic differential…

Category Theory · Mathematics 2017-04-17 Matthew Burke

We introduce the basic notions and present examples and results on Lie categories -- categories internal to the category of smooth manifolds. Demonstrating how the units of a Lie category $\mathcal C$ dictate the behavior of its invertible…

Differential Geometry · Mathematics 2025-02-14 Žan Grad

In this paper, we give an accessible introduction to the theory of orbispaces via groupoids. We define a certain class of topological groupoids, which we call orbigroupoids. Each orbigroupoid represents an orbispace, but just as with…

Category Theory · Mathematics 2014-01-21 Vesta Coufal , Dorette Pronk , Carmen Rovi , Laura Scull , Courtney Thatcher

In this note, we prove that intrinsic characteristic classes of Lie algebroids - which in degree one recover the modular class - behave functorially with respect to arbitrary transverse maps, and in particular are weak Morita invariants. In…

Symplectic Geometry · Mathematics 2018-11-16 Pedro Frejlich

In this work, we show that extending the standard description of space-time symmetries from groups of isometries to the more flexible framework of kinematical groupoids allows for the extension of Wigner's program to curved space-times. We…

Mathematical Physics · Physics 2026-04-08 Alberto Ibort , Giuseppe Marmo , Arnau Mas , Luca Schiavone

Let $L$ be a quantum semigroupoid, more precisely a $\times_R$-bialgebra in the sense of Takeuchi. We describe a procedure replacing the algebra $R$ by any Morita equivalent, or in fact more generally any $\sqrt{\text{Morita}}$ equivalent…

Quantum Algebra · Mathematics 2007-05-23 Peter Schauenburg

Jacobi groupoids are introduced as a generalization of Poisson and contact groupoids and it is proved that generalized Lie bialgebroids are the infinitesimal invariants of Jacobi groupoids. Several examples are discussed.

Differential Geometry · Mathematics 2007-05-23 D. Iglesias , J. C. Marrero

This thesis deals with deformations of VB-algebroids and VB-groupoids. They can be considered as vector bundles in the categories of Lie algebroids and groupoids and encompass several classical objects, including Lie algebra and Lie group…

Differential Geometry · Mathematics 2020-01-22 Pier Paolo La Pastina

Presentations of smooth symmetry groups of differentiable stacks are studied within the framework of the weak 2-category of Lie groupoids, smooth principal bibundles, and smooth biequivariant maps. It is shown that principality of bibundles…

Differential Geometry · Mathematics 2008-07-28 Christian Blohmann

We introduce a new notion of Morita equivalence for diffeological groupoids, generalising the original notion for Lie groupoids. For this we develop a theory of diffeological groupoid actions, -bundles and -bibundles. We define a notion of…

Differential Geometry · Mathematics 2023-03-08 Nesta van der Schaaf

Cartan-Lie algebroids, i.e. Lie algebroids equipped with a compatible connection, permit the definition of an adjoint representation, on the fiber as well as on the tangent of the base. We call (positive) quadratic Lie algebroids,…

Differential Geometry · Mathematics 2018-02-14 Alexei Kotov , Thomas Strobl

We present some features of the smooth structure, and of the canonical stratification on the orbit space of a proper Lie groupoid. One of the main features is that of Morita invariance of these structures - it allows us to talk about the…

Differential Geometry · Mathematics 2017-11-03 Marius Crainic , João Nuno Mestre

We discuss a concept of loopoid as a non-associative generalization of (Brandt) groupoid. We introduce and study also an interesting class of more general objects which we call semiloopoids. A differential version of loopoids is intended as…

Group Theory · Mathematics 2017-01-17 Janusz Grabowski

The f-invariant is a higher version of the e-invariant that takes values in the divided congruences between modular forms; it can be formulated as an elliptic genus of manifolds with corners of codimension two. In this thesis, we develop a…

Differential Geometry · Mathematics 2009-09-22 Hanno von Bodecker

Morita equivalence classes of Lie groupoids serve as models for differentiable stacks, which are higher spaces in differential geometry, generalizing manifolds and orbifolds. Representations up to homotopy of Lie groupoids provide a higher…

Differential Geometry · Mathematics 2024-10-04 Matias del Hoyo , Cristian Ortiz , Fernando Studzinski

Symplectic structures on higher objects like Lie groupoids have been studied for some time now, but not all of the proposed definitions are preserved under Morita equivalence of Lie groupoids, in turn giving rise to a consistent notion of…

Differential Geometry · Mathematics 2026-04-30 Milena Weiershausen