Characterization Of Certain ....-Self-Adjoint Operators By Means Of Their Exponential Function.
Characterization of scalar-type spectral operators
Characterization of unbounded spectral operators with spectrum in a half-line.
Closure of Similarity Orbits of Hubert Space Operators. III.
Cohyponormal operators with the single valued extension property.
Commutative Banach Algebras and Decomposable Operators.
Compact AC-operators
We prove that compact AC-operators have a representation as a combination of disjoint projections which mirrors that for compact normal operators. We also show that unlike arbitrary AC-operators, compact AC-operators admit a unique splitting into real and imaginary parts, and that these parts must necessarily be compact.
Comparison of joint spectra for certain classes of commuting operators
Decomposability of operator-valued functions
Decomposable embeddings, complete trajectories, and invariant subspaces
We produce closed nontrivial invariant subspaces for closed (possibly unbounded) linear operators, A, on a Banach space, that may be embedded between decomposable operators on spaces with weaker and stronger topologies. We show that this can be done under many conditions on orbits, including when both A and A* have nontrivial non-quasi-analytic complete trajectories, and when both A and A* generate bounded semigroups that are not stable.
Decomposable multipliers and applications to harmonic analysis
For a multiplier on a semisimple commutative Banach algebra, the decomposability in the sense of Foiaş will be related to certain continuity properties and growth conditions of its Gelfand transform on the spectrum of the multiplier algebra. If the multiplier algebra is regular, then all multipliers will be seen to be decomposable. In general, an important tool will be the hull-kernel topology on the spectrum of the typically nonregular multiplier algebra. Our investigation involves various closed...
Decomposition of operators with countable spectrum.
Sufficient spectral conditions for the existence of a spectral decomposition of an operator T defined on a Banach space X, with countable spectrum, are given. We apply the results to obtain the West decomposition of certain Riesz operators.
Der spektrale Abbildungssatz für nichtanalytische Funktionalkalküle in mehreren Veränderlichen.
Die erzeugte Algebra eines Markov-Verbandsoperators in C(X).
Direct Integral Decomposition of Spectral Operators.
Direct Integrals of Hilbert Spaces II.
Direct sum of residually decomposable operators
Distributions at infinity for Riemann surfaces
Equivalence of Decomposability and 2-Decomposability for Several Commuting Operators.
Flot hamiltonien et spectre d'un opérateur elliptique