Spectral theory and Cauchy problems on Lp spaces.
Spectral Theory of the Dirac Operator.
Spectrum of a differential operator with periodic generalized potential.
Strong resonant tunneling, level repulsion and spectral type for one-dimensional adiabatic quasi-periodic Schrödinger operators
Sturm-Liouville operator with general boundary conditions.
Sur le théorème de l’indice des équations différentielles -adiques
Sur les injections entre espaces de Sobolev et espaces d'Orlicz et application au comportement a l'infini pour des équations des ondes semi-linéaires
Sur l'intégration directe des équations d'évolution 2
Sur un opérateur différentiel général
Symmetric subspaces related to certain eigenvalue problems
Tensor products of linear operators in locally convex spaces
The Algebraic Multiplicity of Eigenvalues and the Evans Function Revisited
This paper is related to the spectral stability of traveling wave solutions of partial differential equations. In the first part of the paper we use the Gohberg-Rouche Theorem to prove equality of the algebraic multiplicity of an isolated eigenvalue of an abstract operator on a Hilbert space, and the algebraic multiplicity of the eigenvalue of the corresponding Birman-Schwinger type operator pencil. In the second part of the paper we apply this result...
The Cauchy problem for an inclusion in Banach spaces and distribution spaces.
The dependence of the eigenvalues of the Sturm-liouville problem on boundary conditions
The division method for subspectra of self-adjoint differential vector-operators.
The existence of bounded solutions for differential equations in Hilbert spaces
The existence of bounded solutions for equations x' = A(t)x + r(x,t) is proved, where the linear part is exponentially dichotomic and the nonlinear term r satisfies some weak conditions.
The Friedrichs extension of certain singular differential operators. II.
The General Differential Operators Generated by a Quasi-Differential Expressions with their Interior Singular Points
The general ordinary quasi-differential expression M of n-th order with complex coefficients and its formal adjoint M + are considered over a regoin (a, b) on the real line, −∞ ≤ a < b ≤ ∞, on which the operator may have a finite number of singular points. By considering M over various subintervals on which singularities occur only at the ends, restrictions of the maximal operator generated by M in L2|w (a, b) which are regularly solvable with respect to the minimal operators T0 (M ) and T0...
The inverse spectral problem for the Sturm-Liouville operators with discontinuous coefficients.
The operator equation AX - XB = C with unbounded operators A and B and related abstract Cauchy problems.