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Global generalized Bianchi identities for invariant variational problems on gauge-natural bundles

Marcella Palese, Ekkehart Winterroth (2005)

Archivum Mathematicum

We derive both local and global generalized Bianchi identities for classical Lagrangian field theories on gauge-natural bundles. We show that globally defined generalized Bianchi identities can be found without the a priori introduction of a connection. The proof is based on a global decomposition of the variational Lie derivative of the generalized Euler-Lagrange morphism and the representation of the corresponding generalized Jacobi morphism on gauge-natural bundles. In particular, we show that...

Gradient horizontal de fonctions polynomiales

Si Tiep Dinh, Krzysztof Kurdyka, Patrice Orro (2009)

Annales de l’institut Fourier

Nous étudions les trajectoires du gradient sous-riemannien (appellé horizontal) de fonctions polynômes. Dans ce cadre l’inégalité de Łojasiewicz n’est pas valide et une trajectoire du gradient horizontal peut être de longueur infinie, et peut même s’accumuler sur une courbe fermée. Nous montrons que ces comportement sont exceptionnels ; et que, pour une fonction générique les trajectoires de son gradient horizontal ont des propriétés similaires au cas du gradient riemannien. Pour obtenir la finitude...

Growth of a primitive of a differential form

Jean-Claude Sikorav (2001)

Bulletin de la Société Mathématique de France

For an exact differential form on a Riemannian manifold to have a primitive bounded by a given function f , by Stokes it has to satisfy some weighted isoperimetric inequality. We show the converse up to some constants if M has bounded geometry. For a volume form, it suffices to have the inequality ( | Ω | Ω f d σ for every compact domain Ω M ). This implies in particular the “well-known” result that if M is the universal covering of a compact Riemannian manifold with non-amenable fundamental group, then the volume...

Hecke operators on de Rham cohomology.

Min Ho Lee (2004)

Revista Matemática Complutense

We introduce Hecke operators on de Rham cohomology of compact oriented manifolds. When the manifold is a quotient of a Hermitian symmetric domain, we prove that certain types of such operators are compatible with the usual Hecke operators on automorphic forms.

Hidden symmetries of the gravitational contact structure of the classical phase space of general relativistic test particle

Josef Janyška (2014)

Archivum Mathematicum

The phase space of general relativistic test particle is defined as the 1-jet space of motions. A Lorentzian metric defines the canonical contact structure on the odd-dimensional phase space. In the paper we study infinitesimal symmetries of the gravitational contact phase structure which are not generated by spacetime infinitesimal symmetries, i.e. they are hidden symmetries. We prove that Killing multivector fields admit hidden symmetries of the gravitational contact phase structure and we give...

Higher order Cartan connections

Juraj Virsik (1996)

Archivum Mathematicum

A Cartan connection associated with a pair P ( M , G ' ) P ( M , G ) is defined in the usual manner except that only the injectivity of ω : T ( P ' ) T ( G ) e is required. For an r -th order connection associated with a bundle morphism Φ : P ' P the concept of Cartan order q r is defined, which for q = r = 1 , Φ : P ' P , and dim M = dim G / G ' coincides with the classical definition. Results are obtained concerning the Cartan order of r -th order connections that are the product of r first order (Cartan) connections.

Higher order connections.

Eastwood, Michael G. (2009)

SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only]

Currently displaying 341 – 360 of 1152