On compact solvability of differentials of an elliptic differential complex.
On generalized Cauchy-Riemann equations on manifolds
On the cohomology sequence in a semiabelian category.
On the L2 cohomology of complex spaces.
On the Polynomial Cohomology of Affine Manifolds.
Quantization and global properties of manifolds
Quelques souvenirs des années 1925-1950
Remarks on the Lichnerowicz-Poisson cohomology
The paper begins with some general remarks which include the Mayer-Vietoris exact sequence, a covariant version of the Lichnerowicz-Poisson cohomology, and the definition of an associated Serre-Hochshild spectral sequence. Then we consider the regular case, and we discuss the Poisson cohomology by using a natural bigrading of the Lichnerowicz cochain complex. Furthermore, if the symplectic foliation of the Poisson manifold is either transversally Riemannian or transversally symplectic, the spectral...
Second variational derivative of local variational problems and conservation laws
We consider cohomology defined by a system of local Lagrangian and investigate under which conditions the variational Lie derivative of associated local currents is a system of conserved currents. The answer to such a question involves Jacobi equations for the local system. Furthermore, we recall that it was shown by Krupka et al. that the invariance of a closed Helmholtz form of a dynamical form is equivalent with local variationality of the Lie derivative of the dynamical form; we remark that...
Separation of variables in the problems of normal and compact solvability of the exterior derivation operator.
Some Properties of a Cohomology Group Associated to a Totally Geodesic Foliation.
Some remark on the stability problems for de Rham currents.
Some remarks on Lie flows.
The first part of this paper is concerned with geometrical and cohomological properties of Lie flows on compact manifolds. Relations between these properties and the Euler class of the flow are given.The second part deals with 3-codimensional Lie flows. Using the classification of 3-dimensional Lie algebras we give cohomological obstructions for a compact manifold admits a Lie flow transversely modeled on a given Lie algebra.
Stability of Tangential Locally Conformal Symplectic Forms
In this paper we firstly define a tangential Lichnerowicz cohomology on foliated manifolds. Next, we define tangential locally conformal symplectic forms on a foliated manifold and we formulate and prove some results concerning their stability.
Sulla coomologia intera delle varietà differenziabili
Sur la cohomologie feuilletée
Sur la suite exacte canonique associée à un fibré principal
Sur l'unique ergodicité des 1-formes fermées singulières.
Symmetries in finite order variational sequences
We refer to Krupka’s variational sequence, i.e. the quotient of the de Rham sequence on a finite order jet space with respect to a ‘variationally trivial’ subsequence. Among the morphisms of the variational sequence there are the Euler-Lagrange operator and the Helmholtz operator. In this note we show that the Lie derivative operator passes to the quotient in the variational sequence. Then we define the variational Lie derivative as an operator on the sheaves of the variational sequence. Explicit...
The geometry of a closed form
It is proved that a closed r-form ω on a manifold M defines a cohomology (called ω-coeffective) on M. A general algebraic machinery is developed to extract some topological information contained in the ω-coeffective cohomology. The cases of 1-forms, symplectic forms, fundamental 2-forms on almost contact manifolds, fundamental 3-forms on -manifolds and fundamental 4-forms in quaternionic manifolds are discussed.