Displaying 321 – 340 of 729

Showing per page

Lemme de Moser feuilleté et clasifications des variétés de Poisson régulières.

G. Héctor, E. Macías, M. Saralegui (1989)

Publicacions Matemàtiques

Regular Poisson structures with fixed characteristic foliation F are described by means of foliated symplectic forms. Associated to each of these structures, there is a class in the second group of foliated cohomology H2(F). Using a foliated version of Moser's lemma, we study the isotopy classes of these structures in relation with their cohomology class. Explicit examples, with dim F = 2, are described.

Lie Algebra bundles on s-Kähler manifolds, with applications to Abelian varieties

Giovanni Gaiffi, Michele Grassi (2010)

Annales de la faculté des sciences de Toulouse Mathématiques

We prove that one can obtain natural bundles of Lie algebras on rank two s -Kähler manifolds, whose fibres are isomorphic respectively to so ( s + 1 , s + 1 ) , su ( s + 1 , s + 1 ) and sl ( 2 s + 2 , ) . These bundles have natural flat connections, whose flat global sections generalize the Lefschetz operators of Kähler geometry and act naturally on cohomology. As a first application, we build an irreducible representation of a rational form of su ( s + 1 , s + 1 ) on (rational) Hodge classes of Abelian varieties with rational period matrix.

Lifts of Foliated Linear Connectionsto the Second Order Transverse Bundles

Vadim V. Shurygin, Svetlana K. Zubkova (2016)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

The second order transverse bundle T 2 M of a foliated manifold M carries a natural structure of a smooth manifold over the algebra 𝔻 2 of truncated polynomials of degree two in one variable. Prolongations of foliated mappings to second order transverse bundles are a partial case of more general 𝔻 2 -smooth foliated mappings between second order transverse bundles. We establish necessary and sufficient conditions under which a 𝔻 2 -smooth foliated diffeomorphism between two second order transverse bundles maps...

Liouville forms in a neighborhood of an isotropic embedding

Frank Loose (1997)

Annales de l'institut Fourier

A Liouville form on a symplectic manifold ( X , ω ) is by definition a potential β of the symplectic form - d β = ω . Its center M is given by β - 1 ( 0 ) . A normal form for certain Liouville forms in a neighborhood of its center is given.

Manifolds admitting stable forms

Hông-Van Lê, Martin Panák, Jiří Vanžura (2008)

Commentationes Mathematicae Universitatis Carolinae

In this note we give a direct method to classify all stable forms on n as well as to determine their automorphism groups. We show that in dimensions 6, 7, 8 stable forms coincide with non-degenerate forms. We present necessary conditions and sufficient conditions for a manifold to admit a stable form. We also discuss rich properties of the geometry of such manifolds.

Maslov indices on the metaplectic group M p ( n )

Maurice De Gosson (1990)

Annales de l'institut Fourier

We use the properties of M p ( n ) to construct functions μ : M p ( n ) Z 8 associated with the elements of the lagrangian grassmannian Λ (n) which generalize the Maslov index on Mp(n) defined by J. Leray in his “Lagrangian Analysis”. We deduce from these constructions the identity between M p ( n ) and a subset of S p ( n ) × Z 8 , equipped with appropriate algebraic and topological structures.

Metric of special 2F-flat Riemannian spaces

Raad J. K. al Lami (2005)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

In this paper we find the metric in an explicit shape of special 2 F -flat Riemannian spaces V n , i.e. spaces, which are 2 F -planar mapped on flat spaces. In this case it is supposed, that F is the cubic structure: F 3 = I .

Currently displaying 321 – 340 of 729