Tauberian operators in -adic analysis.
The adjoint theorem on A-spaces.
The carrier graph topology.
The curvature function and similarity of operators
The Fuglede–Putnam theorem for -quasihyponormal operators.
The Hilbert projective metric and an equation in a -algebra
The only continuous Volterra right inverses in of the operator are
The pseudodifferential operator .
The stability radius of an operator of Saphar type
A bounded linear operator T on a complex Banach space X is called an operator of Saphar type if its kernel is contained in its generalized range and T is relatively regular. For T of Saphar type we determine the supremum of all positive numbers δ such that T - λI is of Saphar type for |λ| < δ.
Three remarks on the use of Čebyšev polynomials for solving equations of the second kind
Toeplitz operators in the commutant of a composition operator
If ϕ is an analytic self-mapping of the unit disc D and if is the Hardy-Hilbert space on D, the composition operator on is defined by . In this article, we consider which Toeplitz operators satisfy
Towards a "Matrix Theory" for Unbounded Operator Matrices.
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 .
Transitivity for linear operators on a Banach space
Let G be the multiplicative group of invertible elements of E(X), the algebra of all bounded linear operators on a Banach space X. In 1945 Mackey showed that if and are any two sets of linearly independent elements of X with the same number of items, then there exists T ∈ G so that , . We prove that some proper multiplicative subgroups of G have this property.
Two centuries of the term "algebraic analysis"
The term "Algebraic Analysis" in the last two decades is used in two completely different senses. It seems that at least one is far away from its historical roots. Thus, in order to explain this misunderstanding, the history of this term from its origins is recalled.