English
Related papers

Related papers: The modular class of a singular foliation

200 papers

In this article, we first describe codimension two regular foliations with numerically trivial canonical class on complex projective manifolds whose canonical class is not numerically effective. Building on a recent algebraicity criterion…

Algebraic Geometry · Mathematics 2023-06-22 Stéphane Druel

An orbit-like foliation is a singular foliation on a complete Riemannian manifold $M$ whose leaves are locally equidistant (i.e., a singular Riemannian foliation) and (transversely) infinitesimally homogenous. This class of singular…

Differential Geometry · Mathematics 2021-11-29 Marcos M. Alexandrino , Leonardo F. Cavenaghi

In the first part of this paper, we propose a uniform interpretation of characteristic classes as obstructions to the reduction of the structure group and to the existence of an equivariant extension of a certain homomorphism defined a…

Algebraic Topology · Mathematics 2018-10-16 Martina Rovelli

We extend the notion of connection in order to be able to study singular geometric structures, namely, we consider a notion of connection on a Lie algebroid which is a natural extension of the usual concept of connection. Using connections,…

Differential Geometry · Mathematics 2007-05-23 Rui Loja Fernandes

In order to understand the linearization problem around a leaf of a singular foliation, we extend the familiar holonomy map from the case of regular foliations to the case of singular foliations. To this aim we introduce the notion of…

Differential Geometry · Mathematics 2014-09-12 Iakovos Androulidakis , Marco Zambon

In this article, we introduce and study singular foliations of $b^k$-type. These singular foliations formalize the properties of vector fields that are tangent to order $k$ along a submanifold $W \subset M$. Our first result is a…

Differential Geometry · Mathematics 2023-11-29 Francis Bischoff , Álvaro del Pino , Aldo Witte

In this note we revisit the notions of transverse density bundle and of modular classes of Lie algebroids and Lie groupoids; in particular, we point out that one should use the transverse density bundle $\mathcal{D}_{A}^{\textrm{tr}}$…

Differential Geometry · Mathematics 2020-04-15 Marius Crainic , João Nuno Mestre

This work concerns the problem of relating characteristic numbers of one-dimensional holomorphic foliations of P^n to those of algebraic varieties invariant by them. More precisely: if M is a connected complex manifold, a one-dimensional…

Complex Variables · Mathematics 2016-09-07 Marcio G. Soares

We study the modular class of $Q$-manifolds, and in particular of negatively graded Lie $\infty$-algebroid. We show the equivalence of several descriptions of those classes, that it matches the classes introduced by various authors and that…

Differential Geometry · Mathematics 2022-03-31 Raquel Caseiro , Camille Laurent-Gengoux

For a Lie algebroid, divergences chosen in a classical way lead to a uniquely defined homology theory. They define also, in a natural way, modular classes of certain Lie algebroid morphisms. This approach, applied for the anchor map,…

Differential Geometry · Mathematics 2008-11-26 Janusz Grabowski , Giuseppe Marmo , Peter W. Michor

We describe a construction of the modular class associated to a representation up to homotopy of a Lie groupoid. In the case of the adjoint representation up to homotopy, this class is the obstruction to the existence of a volume form, in…

Differential Geometry · Mathematics 2015-07-28 Rajan Amit Mehta

Recently, a geometrical characterization of vector spaces served to generalize them into a new class of algebras. Instead of the algebraic properties of the underlying fields, we generalized the recently discovered property of such spaces…

Algebraic Geometry · Mathematics 2019-01-23 Gabriele Ricci

Using Quillen-Lurie deformation theory formalism we develop an obstruction theory for studying the stable $\infty$-category of modules over a given geometric $\infty$-stack. The obstruction theory studies the problem of lifting compact…

Algebraic Geometry · Mathematics 2012-12-11 Romie Banerjee

We study the moduli space of four dimensional ordinary Lie algebras, and their versal deformations. Their classification is well known; our focus in this paper is on the deformations, which yield a picture of how the moduli space is…

Representation Theory · Mathematics 2007-05-23 Alice Fialowski , Michael Penkava

We show that an everywhere regular foliation $\mathcal F$ with compact canonically polarized leaves on a quasi-projective manifold $X$ has isotrivial family of leaves when the orbifold base of this family is special. By a recent work of…

Algebraic Geometry · Mathematics 2017-09-22 Ekaterina Amerik , Frédéric Campana

This paper contributes to the solution of the Poincare problem, which is to bound the degree of a (generalized algebraic) leaf of a (singular algebraic) foliation of the complex projective plane. The first theorem gives a new sort of bound,…

Algebraic Geometry · Mathematics 2007-05-23 E. Esteves , S. Kleiman

In this article we apply ideas from homotopy theory to the study of singular foliations. We verify that a technical lemma remains valid for left semi-model categories. When applied to the category of $L_\infty$-algebroids thanks to the work…

Algebraic Topology · Mathematics 2019-09-04 Yael Fregier , Rigel A. Juarez-Ojeda

We introduce the concept of Loday algebroids, a generalization of Courant algebroids. We define the naive cohomology and modular class of a Loday algebroid, and we show that the modular class of the double of a Lie bialgebroid vanishes. For…

Differential Geometry · Mathematics 2008-03-17 Mathieu Stienon , Ping Xu

Let $\Lambda$ be a finite dimensional algebra over an algebraically closed field. Criteria are given which characterize existence of a fine or coarse moduli space classifying, up to isomorphism, the representations of $\Lambda$ with fixed…

Representation Theory · Mathematics 2014-07-11 Birge Huisgen-Zimmermann

This work deals with the topological classification of germs of singular foliations on $(\mathbb C^{2},0)$. Working in a suitable class of foliations we fix the topological invariants given by the separatrix set, the Camacho-Sad indices and…

Dynamical Systems · Mathematics 2017-09-19 David Marín , Jean-François Mattei , Éliane Salem