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Sprays and homogeneous connections on 𝐑 × 𝑇𝑀

Alexandr Vondra (1992)

Archivum Mathematicum

The homogeneity properties of two different families of geometric objects playing a crutial role in the non-autonomous first-order dynamics - semisprays and dynamical connections on R × T M - are studied. A natural correspondence between sprays and a special class of homogeneous connections is presented.

Stabilities of F-Yang-Mills fields on submanifolds

Gao-Yang Jia, Zhen Rong Zhou (2013)

Archivum Mathematicum

In this paper, we define an F -Yang-Mills functional, and hence F -Yang-Mills fields. The first and the second variational formulas are calculated, and the stabilities of F -Yang-Mills fields on some submanifolds of the Euclidean spaces and the spheres are investigated, and hence the theories of Yang-Mills fields are generalized in this paper.

Structure presque tangente et connexions I

Joseph Grifone (1972)

Annales de l'institut Fourier

On donne une nouvelle définition des connexions non linéaires et, plus généralement des connexions non homogènes, en faisant intervenir la structure presque tangente naturelle du fibré tangent.Ceci permet d’établir intrinsèquement les équations différentielles qui lient une connexion à sa gerbe.Ce formalisme est ensuite appliqué à l’étude des connexions sur une variété finslérienne et sur un système mécanique : on obtient dans le cas finslérien une généralisation du “théorème fondamental de la géométrie...

Sur les actions affines des groupes discrets

Abdelghani Zeghib (1997)

Annales de l'institut Fourier

On pourrait espérer “classifier” les actions différentiables en préservant le volume des réseaux de SL ( n , ) sur les variétés compactes. On en est cependant loin. Ainsi, plusieurs auteurs ont récemment étudié les actions des réseaux de SL ( n , ) sur des variétés de dimension relativement basse, précisément, n , et vérifiant en plus certaines conditions géométriques ou dynamiques. On montre alors qu’il s’agit essentiellement de l’action usuelle de SL ( n , ) sur un tore de dimension n . Ici, on généralise ce fait aux actions...

Symmetries of connections on fibered manifolds

Alexandr Vondra (1994)

Archivum Mathematicum

The (infinitesimal) symmetries of first and second-order partial differential equations represented by connections on fibered manifolds are studied within the framework of certain “strong horizontal“ structures closely related to the equations in question. The classification and global description of the symmetries is presented by means of some natural compatible structures, eġḃy vertical prolongations of connections.

Symplectic connections with parallel Ricci tensor

Michel Cahen, Simone Gutt, John Rawnsley (2000)

Banach Center Publications

A variational principle introduced to select some symplectic connections leads to field equations which, in the case of the Levi Civita connection of Kähler manifolds, are equivalent to the condition that the Ricci tensor is parallel. This condition, which is stronger than the field equations, is studied in a purely symplectic framework.

The Bellaterra connection.

Jaak Peetre (1993)

Publicacions Matemàtiques

A new object is introduced - the "Fischer bundle". It is, formally speaking, an Hermitean bundle of infinite rank over a bounded symmetric domain whose fibers are Hilbert spaces whose elements can be realized as entire analytic functions square integrable with respect to a Gaussian measure ("Fischer spaces"). The definition was inspired by our previous work on the "Fock bundle". An even more general framework is indicated, which allows one to look upon the two concepts from a unified point of view....

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