Add to ORKGIt is well known that the identity is an operator with the following property: if the operator, initially defined on an n-dimensional Banach space V, can be extended to any Banach space with norm 1, then V is isometric to ℓ∞(n). We show that the set of all such operators consists precisely of those with spectrum lying in the unit circle. This result answers a question raised in [5] for complex spaces
AbstractLet T be a bounded linear operator on a complex banach space X. The following essential spec...
AbstractLet T be an invertible positive operator on a Banach lattice E such that the number 0 belong...
The book presents an introduction to the geometry of Hilbert spaces and operator theory, targeting g...
It is well known that the identity is an operator with the following property: if the operator, init...
Abstract. It is well known that the identity is an operator with the following property: if the oper...
AbstractIt is well known that, if an identity operator on an n-dimensional Banach space V can be ext...
AbstractIt is well known that, if the identity operator on an n-dimensional Banach space V can be ex...
, where A ∈ (X), B ∈ (Y), C ∈ (Y,X), and X, Y are complex Banach spaces. We prove that (SA ∗ ∩SB)∪σ(...
AbstractWe find necessary and sufficient conditions for a Banach space operator T to satisfy the gen...
This book is dedicated to the spectral theory of linear operators on Banach spaces and of elements i...
In this paper we investigate inverse eigenvalue problems for finite spectrum linear isometries on co...
AbstractLet Y be a closed subspace of Lp(μ), where μ is an arbitrary measure and 1 < p < ∞. It is sh...
Abstract. The role of spectral theory of linear operators in qualitative theory of ordinary differen...
Abstract. Let E be a closed subset of the unit circle. A result of Nikolski shows that, if T is an o...
Introduction. The spectral mapping theorem states, among other things, that if f is an analytic func...
AbstractLet T be a bounded linear operator on a complex banach space X. The following essential spec...
AbstractLet T be an invertible positive operator on a Banach lattice E such that the number 0 belong...
The book presents an introduction to the geometry of Hilbert spaces and operator theory, targeting g...
It is well known that the identity is an operator with the following property: if the operator, init...
Abstract. It is well known that the identity is an operator with the following property: if the oper...
AbstractIt is well known that, if an identity operator on an n-dimensional Banach space V can be ext...
AbstractIt is well known that, if the identity operator on an n-dimensional Banach space V can be ex...
, where A ∈ (X), B ∈ (Y), C ∈ (Y,X), and X, Y are complex Banach spaces. We prove that (SA ∗ ∩SB)∪σ(...
AbstractWe find necessary and sufficient conditions for a Banach space operator T to satisfy the gen...
This book is dedicated to the spectral theory of linear operators on Banach spaces and of elements i...
In this paper we investigate inverse eigenvalue problems for finite spectrum linear isometries on co...
AbstractLet Y be a closed subspace of Lp(μ), where μ is an arbitrary measure and 1 < p < ∞. It is sh...
Abstract. The role of spectral theory of linear operators in qualitative theory of ordinary differen...
Abstract. Let E be a closed subset of the unit circle. A result of Nikolski shows that, if T is an o...
Introduction. The spectral mapping theorem states, among other things, that if f is an analytic func...
AbstractLet T be a bounded linear operator on a complex banach space X. The following essential spec...
AbstractLet T be an invertible positive operator on a Banach lattice E such that the number 0 belong...
The book presents an introduction to the geometry of Hilbert spaces and operator theory, targeting g...