Spectral representation of local semigroups in locally convex spaces
Spectral Representations for Unbounded Operators with Real Spectrum.
Spektrale Invarianz bei verallgemeinerten Eigenfunktionsentwicklungen.
Stability of the method of least squares for finding the eigenvalues of a symmetric operator
Straight quantum waveguide with Robin boundary conditions.
Strong uniqueness for certain infinite dimensional Dirichlet operators and applications to stochastic quantization
Symmetric perturbation of a self-adjoint operator
Symmetric subspaces related to certain eigenvalue problems
The conjugate of the product of operators
The density of states of a local almost periodic operator in
We prove the existence of the density of states of a local, self-adjoint operator determined by a coercive, almost periodic quadratic form on . The support of the density coincides with the spectrum of the operator in .
The division method for subspectra of self-adjoint differential vector-operators.
The Friedrichs extension of certain singular differential operators. II.
The Krein string and characteristic functions of non-self-adjoint operators.
The linear symmetric systems associated with the modified Cherednik operators and applications
We introduce and study the linear symmetric systems associated with the modified Cherednik operators. We prove the well-posedness results for the Cauchy problem for these systems. Eventually we describe the finite propagation speed property of it.
The Ornstein-Uhlenbeck generator perturbed by the gradient of a potential
Si considera, in uno spazio di Hilbert l'operatore lineare , dove è un operatore negative autoaggiunto e è un potenziale che soddisfa a opportune condizioni di integrabilità. Si dimostra con un metodo analitico che è essenzialmente autoaggiunto in uno spazio e si caratterizza il dominio della sua chiusura come sottospazio di . Si studia inoltre la «spectral gap property» del semigruppo generato da .
The Sturm-Liouville Friedrichs extension
The characterization of the domain of the Friedrichs extension as a restriction of the maximal domain is well known. It depends on principal solutions. Here we establish a characterization as an extension of the minimal domain. Our proof is different and closer in spirit to the Friedrichs construction. It starts with the assumption that the minimal operator is bounded below and does not directly use oscillation theory.
Théorie spectrale
Towards a theory of some unbounded linear operators on -adic Hilbert spaces and applications
We are concerned with some unbounded linear operators on the so-called -adic Hilbert space . Both the Closedness and the self-adjointness of those unbounded linear operators are investigated. As applications, we shall consider the diagonal operator on , and the solvability of the equation where is a linear operator on .
Über die Selbstadjungiertheit von Schrödinger Operatoren.
Ultrapowers of unbounded selfadjoint operators