Maximal Hamiltonian tori for polygon spaces
We study the poset of Hamiltonian tori for polygon spaces. We determine some maximal elements and give examples where maximal Hamiltonian tori are not all of the same dimension.
Metric with ergodic geodesic flow is completely determined by unparameterized geodesics.
Métriques à entropie topologique positive sur
Métriques kählériennes à courbure scalaire constante : unicité, stabilité
Un des problèmes les plus intéressants de la géométrie différentielle complexe consiste à comprendre les classes de Kähler de variétés complexes admettant des métriques à courbure scalaire constante. La question de l’unicité a été récemment résolue par Donaldson, Mabuchi, Chen–Tian. Des liens forts avec la stabilité algébrique des variétés ont été mis en évidence. L’exposé s’attachera à exposer les idées nouvelles qui ont mené à ces résultats.
Minimal Reeb vector fields on almost Kenmotsu manifolds
A necessary and sufficient condition for the Reeb vector field of a three dimensional non-Kenmotsu almost Kenmotsu manifold to be minimal is obtained. Using this result, we obtain some classifications of some types of -almost Kenmotsu manifolds. Also, we give some characterizations of the minimality of the Reeb vector fields of -almost Kenmotsu manifolds. In addition, we prove that the Reeb vector field of an almost Kenmotsu manifold with conformal Reeb foliation is minimal.
Modèles locaux de structures de Poisson singulières en dimension 3
Modular classes of Q-manifolds: a review and some applications
A Q-manifold is a supermanifold equipped with an odd vector field that squares to zero. The notion of the modular class of a Q-manifold – which is viewed as the obstruction to the existence of a Q-invariant Berezin volume – is not well know. We review the basic ideas and then apply this technology to various examples, including -algebroids and higher Poisson manifolds.
Modular vector fields and Batalin-Vilkovisky algebras
We show that a modular class arises from the existence of two generating operators for a Batalin-Vilkovisky algebra. In particular, for every triangular Lie bialgebroid (A,P) such that its top exterior power is a trivial line bundle, there is a section of the vector bundle A whose -cohomology class is well-defined. We give simple proofs of its properties. The modular class of an orientable Poisson manifold is an example. We analyse the relationships between generating operators of the Gerstenhaber...
Moving frames, Geometric Poisson brackets and the KdV-Schwarzian evolution of pure spinors
In this paper we describe a non-local moving frame along a curve of pure spinors in , and its associated basis of differential invariants. We show that the space of differential invariants of Schwarzian-type define a Poisson submanifold of the spinor Geometric Poisson brackets. The resulting restriction is given by a decoupled system of KdV Poisson structures. We define a generalization of the Schwarzian-KdV evolution for pure spinor curves and we prove that it induces a decoupled system of KdV...
Multicontact vector fields on Hessenberg manifolds.
Multiple Bernoulli series, an Euler-MacLaurin formula, and Wall crossings
We study multiple Bernoulli series associated to a sequence of vectors generating a lattice in a vector space. The associated multiple Bernoulli series is a periodic and locally polynomial function, and we give an explicit formula (called wall crossing formula) comparing the polynomial densities in two adjacent domains of polynomiality separated by a hyperplane. We also present a formula in the spirit of Euler-MacLaurin formula. Finally, we give a decomposition formula for the Bernoulli series describing...
Multiple Hamiltonian structures for the Ishii's equation.
Multiple quantum products in toric varieties.
Multiplicative integrable models from Poisson-Nijenhuis structures
We discuss the role of Poisson-Nijenhuis (PN) geometry in the definition of multiplicative integrable models on symplectic groupoids. These are integrable models that are compatible with the groupoid structure in such a way that the set of contour levels of the hamiltonians in involution inherits a topological groupoid structure. We show that every maximal rank PN structure defines such a model. We consider the examples defined on compact hermitian symmetric spaces studied by F. Bonechi, J. Qiu...
Multiplicity-free complex manifolds.
Nambu-Lie group actions.
Nambu-Lie groups.
Nambu-Poisson Tensors on Lie Groups
First as an application of the local structure theorem for Nambu-Poisson tensors, we characterize them in terms of differential forms. Secondly left invariant Nambu-Poisson tensors on Lie groups are considered.
Natural and projectively invariant quantizations on supermanifolds.
Natural transformations of symplectic structures into Poisson's and Jacobi's brackets
A complete classification of natural transformations of symplectic structures into Poisson's brackets as well as into Jacobi's brackets is given.