Spectre conjoint d'opérateurs pseudodifférentiels qui commutent
Spectre de l'équation de Schrödinger, application à la stabilité de la matière
Spectre de l'opérateur de transport
Spectre d'ordre supérieur et problèmes aux limites quasi-linéaires
Nello studio dei problemi del tipo , si impongono generalmente delle condizione sul comportamento asintotico di rispetto allo spettro di . Avendo in vista dei problemi quasilineari del tipo , sembra naturale introdurre una nozione di spettro per che tenga conto della dipendenza del membro di destra rispetto al gradiende . L'oggetto di questo lavoro è di definire, studiare e applicare questa nuova nozione di spettro.
Spectre du noyau intégral
On construit les fonctions propres sur et les valeurs caractéristiques du noyau de Hilbert-Schmidt . Le spectre est donné par la solution d’une équation transcendante dont le comportement asymptotique est .
Spectres d'opérateurs et géométrie des Espaces de Banach [Book]
Spectrum for a solvable Lie algebra of operators
A new concept of spectrum for a solvable Lie algebra of operators is introduced, extending the Taylor spectrum for commuting tuples. This spectrum has the projection property on any Lie subalgebra and, for algebras of compact operators, it may be computed by means of a variant of the classical Ringrose theorem.
Spectrum of a differential operator with periodic generalized potential.
Spectrum of class operators.
Spectrum of compact weighted composition operators on the weighted Hardy space in the unit ball.
Spectrum of generators of a noncommutative Banach algebra
Spectrum of infinite block matrices and -triangular operators.
Spectrum preserving linear mappings in Banach algebras
Let A and B be two unitary Banach algebras. We study linear mappings from A into B which preserve the polynomially convex hull of the spectrum. In particular, we give conditions under which such surjective linear mappings are Jordan morphisms.
Spektrale Invarianz bei verallgemeinerten Eigenfunktionsentwicklungen.
Spektraltheorie linksdefiniter Differenzengleichungssysteme.
Spektraltheorie stetiger Endomorphismen eines lokal-konvexen Raumes.
Spherical semiclassical states of a critical frequency for Schrödinger equations with decaying potentials
For singularly perturbed Schrödinger equations with decaying potentials at infinity we construct semiclassical states of a critical frequency concentrating on spheres near zeroes of the potentials. The results generalize some recent work of Ambrosetti–Malchiodi–Ni [3] which gives solutions concentrating on spheres where the potential is positive. The solutions we obtain exhibit different behaviors from the ones given in [3].
Splines and pseudo-inverses
Splitting quasinorms and metric approximation properties
Square functions, bounded analytic semigroups, and applications
To any bounded analytic semigroup on Hilbert space or on -space, one may associate natural ’square functions’. In this survey paper, we review old and recent results on these square functions, as well as some extensions to various classes of Banach spaces, including noncommutative -spaces, Banach lattices, and their subspaces. We give some applications to functional calculus, similarity problems, multiplier theory, and control theory.