Fréchet differentiability, strict differentiability and subdifferentiability
Fréchet directional differentiability and Fréchet differentiability
Zaj’ıček has recently shown that for a lower semi-continuous real-valued function on an Asplund space, the set of points where the function is Fréchet subdifferentiable but not Fréchet differentiable is first category. We introduce another variant of Fréchet differentiability, called Fréchet directional differentiability, and show that for any real-valued function on a normed linear space, the set of points where the function is Fréchet directionally differentiable but not Fréchet differentiable...
Fredholm alternatives and surjectivity results for multivalued -proper and condensing mappings with applications to nonlinear integral and differential equations
Fredholm determinant of an integral operator driven by a diffusion process.
Fredholm spectrum and growth of cohomology groups
Let T ∈ L(E)ⁿ be a commuting tuple of bounded linear operators on a complex Banach space E and let be the non-essential spectrum of T. We show that, for each connected component M of the manifold of all smooth points of , there is a number p ∈ 0, ..., n such that, for each point z ∈ M, the dimensions of the cohomology groups grow at least like the sequence with d = dim M.
Free loop spaces and cyclohedra
It is well-known that a based space is of the weak homotopy type of a loop space iff it is a grouplike algebra over an -operad. The classical model for such an operad consists of Stasheff’s associahedra. The present paper describes a similar recognition principle for free loop spaces. Let be an operad, a -module and a -algebra. An -trace over consists of a space and a module homomorphism over the operad homomorphism given by the algebra structure on . Let be the little 1-cubes...
Free subgroups of diffeomorphism groups
Free systems of vector fields (d'après L. Hörmander et A. Melin)
Free vibrations for the equation of a rectangular thin plate
In the paper, we deal with the equation of a rectangular thin plate with a simply supported boundary. The restoring force being an odd superlinear function of the vertical displacement, the existence of infinitely many nonzero time-periodic solutions is proved.
Frobenius avec singularités
From astrology to topology via Feynman diagrams and Lie algebras
Summary of the three lectures. These notes are available electronically at http://www.ma.huji.ac.il/~drorbn/Talks/Srni-9901/notes.html.
From Banach to distributions and currents
From elementary algebra to Bäcklund transformations
From Finsler geometry to noncommutative geometry.
From Poisson algebras to Gerstenhaber algebras
Constructing an even Poisson algebra from a Gerstenhaber algebra by means of an odd derivation of square 0 is shown to be possible in the category of Loday algebras (algebras with a non-skew-symmetric bracket, generalizing the Lie algebras, heretofore called Leibniz algebras in the literature). Such “derived brackets” give rise to Lie brackets on certain quotient spaces, and also on certain Abelian subalgebras. The construction of these derived brackets explains the origin of the Lie bracket on...
From the Fermi-Walker to the Cartan connection
Let be a -manifold with a Riemannian conformal structure . Given a regular curve on , the authors define a linear operator on the space of (differentiable) vector fields along , only depending on , called the Fermi-Walker connection along . Then, the authors introduce the concept of Fermi-Walker parallel vector field along , proving that such vector fields set up a linear space isomorphic to the tangent space at a point of . This allows to consider the Fermi-Walker horizontal lift of...
Front d’onde à l’infini pour l’équation de Schrödinger
Front d'onde analytique au bord II
Front d'onde et propagation des singularités pour un vecteur-distribution
We define the wave front set of a distribution vector of a unitary representation in terms of pseudo-differential-like operators [M2] for any real Lie group G. This refines the notion of wave front set of a representation introduced by R. Howe [Hw]. We give as an application a necessary condition so that a distribution vector remains a distribution vector for the restriction of the representation to a closed subgroup H, and we give a propagation of singularities theorem for distribution vectors.
Front propagation for nonlinear diffusion equations on the hyperbolic space
We study the Cauchy problem in the hyperbolic space for the semilinear heat equation with forcing term, which is either of KPP type or of Allen-Cahn type. Propagation and extinction of solutions, asymptotical speed of propagation and asymptotical symmetry of solutions are addressed. With respect to the corresponding problem in the Euclidean space new phenomena arise, which depend on the properties of the diffusion process in . We also investigate a family of travelling wave solutions, named...