Poisson structures on cotangent bundles.
Poisson structures on Weil bundles.
Poisson transforms for differential forms
We give a construction of a Poisson transform mapping density valued differential forms on generalized flag manifolds to differential forms on the corresponding Riemannian symmetric spaces, which can be described entirely in terms of finite dimensional representations of reductive Lie groups. Moreover, we will explicitly generate a family of degree-preserving Poisson transforms whose restriction to real valued differential forms has coclosed images. In addition, as a transform on sections of density...
Poisson-Lie groupoids and the contraction procedure
On the level of Lie algebras, the contraction procedure is a method to create a new Lie algebra from a given Lie algebra by rescaling generators and letting the scaling parameter tend to zero. One of the most well-known examples is the contraction from 𝔰𝔲(2) to 𝔢(2), the Lie algebra of upper-triangular matrices with zero trace and purely imaginary diagonal. In this paper, we will consider an extension of this contraction by taking also into consideration the natural bialgebra structures on these...
Poisson–Lie sigma models on Drinfel’d double
Poisson sigma models represent an interesting use of Poisson manifolds for the construction of a classical field theory. Their definition in the language of fibre bundles is shown and the corresponding field equations are derived using a coordinate independent variational principle. The elegant form of equations of motion for so called Poisson-Lie groups is derived. Construction of the Poisson-Lie group corresponding to a given Lie bialgebra is widely known only for coboundary Lie bialgebras. Using...
Polarités définies par un triangle
Une polarité d’un plan projectif est une application, souvent involutive, envoyant un point générique sur une droite générique et réciproquement. La polarité la plus classique est la polarité par rapport à une conique, mais d’autres existent : la polarité harmonique par rapport à un triangle, les polarités par rapport à une courbe algébrique de degré supérieur, la polarité par rapport à un convexe.Dans cet article nous introduisons une notion de polarité par rapport à un triangle du plan projectif,...
Polkonfigurationen in der äquiformen Kinematik
Im allgemeinen ist die relative Momentanbewegung zweier komplanarer ähnlich-veränderlicher Systeme als Spiralung um einen aufzufassen (Abb. J.). Die bei drei Systemen auftretenden drei Pole bestimmen einen
Polokanonický reper sítě na ploše v trojrozměrném afinním prostoru
Polyèdres finis de dimension 2 à courbure et de rang 2
On définit localement la notion de polyèdre de rang deux pour un polyèdre fini de dimension deux à courbure négative ou nulle. On montre que le revêtement universel d’un tel espace est soit le produit de deux arbres, soit un immeuble de Tits euclidien de rang deux.
Polyhedral realisation of hyperbolic metrics with conical singularities on compact surfaces
A Fuchsian polyhedron in hyperbolic space is a polyhedral surface invariant under the action of a Fuchsian group of isometries (i.e. a group of isometries leaving globally invariant a totally geodesic surface, on which it acts cocompactly). The induced metric on a convex Fuchsian polyhedron is isometric to a hyperbolic metric with conical singularities of positive singular curvature on a compact surface of genus greater than one. We prove that these metrics are actually realised by exactly one convex...
Polynomial growth harmonic functions on complete Riemannian manifolds.
In this paper, we give a sharp estimate on the dimension of the space of polynomial growth harmonic functions with fixed degree on a complete Riemannian manifold, under various assumptions.
Polynomial mappings of polynomial structures with simple roots
Polynomial structures on principal fibre bundles
Polynomial structures with double roots
Polynomial translation surfaces of Weingarten types in Euclidean 3-space
In this paper, we classify polynomial translation surfaces in Euclidean 3-space satisfying the Jacobi condition with respect to the Gaussian curvature, the mean curvature and the second Gaussian curvature.
Ponceletsche Dreieckscharen.
Pontrjagin forms of quaternion manifolds.
Si dimostra che per le varietà a struttura quaternionale generalizzata integrabile, le classi di Pontrjagin sono generate dalle classi di Pontrjagin del fibrato vettoriale fondamentale.
Pontryagin algebra of a transitive Lie algebroid
[For the entire collection see Zbl 0699.00032.] It was previously known that for every principal fibre bundle P there is some corresponding transitive Lie algebroid A(P) - a vector bundle equipped with some structure like the structure of a Lie algebra in the module of sections. The author of this article shows that the Chern-Weil homomorphism of P is a notion of the Lie algebroid of P, i.e. knowing only A(P) of P one can uniquely reproduce the ring of invariant polynomials and the Chern-Weil...
Pontryagin forms on homogeneous spaces.
Porous media equation on locally finite graphs
In this paper, we consider two typical problems on a locally finite connected graph. The first one is to study the Bochner formula for the Laplacian operator on a locally finite connected graph. The other one is to obtain global nontrivial nonnegative solution to porous-media equation via the use of Aronson-Benilan argument. We use the curvature dimension condition to give a characterization two point graph. We also give a porous-media equation criterion about stochastic completeness of the graph....