Results 1 to 10 of about 4,474 (273)
Finite-rank intermediate Hankel operators on the Bergman space [PDF]
International Journal of Mathematics and Mathematical Sciences, 2001 Let L2=L2(D,r dr dθ/π) be the Lebesgue space on the open unit disc and let La2=L2∩ℋol(D) be the Bergman space. Let P be the orthogonal projection of L2 onto La2 and let Q be the orthogonal projection onto L¯a,02={g∈L2;g¯∈La2, g(0)=0}. Then I−P≥Q.
Takahiko Nakazi, Tomoko Osawa
doaj +5 more sources
On the stability of the representation of finite rank operators [PDF]
Advances in Computational Mathematics, 2023 AbstractThe stability of the representation of finite rank operators in terms of a basis is analyzed. A conditioning is introduced as a measure of the stability properties. This conditioning improves some other conditionings because it is closer to the Lebesgue function.
J. M. Carnicer, E. Mainar, J.M. Peña
openalex +4 more sources
On operators commuting with Toeplitz operators modulo the finite rank operators
Journal of Functional Analysis, 2004 AbstractLet X be a bounded linear operator on the Hardy space H2 of the unit disk. We show that if X−Tθ∗XTθ is of finite rank for every inner function θ, then X=Tϕ+F for some Toeplitz operator Tϕ and some finite rank operator F on H2. This solves a variant of an open question where the compactness replaces the finite rank conditions.
Caixing Gu
openalex +3 more sources
Truncated Toeplitz operators of finite rank
Proceedings of the American Mathematical Society, 2012 We give a complete description of the finite-rank truncated Toeplitz operators.
Roman Bessonov
openalex +5 more sources
A hypercyclic finite rank perturbation of a unitary operator [PDF]
Mathematische Annalen, 2010 A unitary operator $V$ and a rank $2$ operator $R$ acting on a Hilbert space $\H$ are constructed such that $V+R$ is hypercyclic. This answers affirmatively a question of Salas whether a finite rank perturbation of a hyponormal operator can be supercyclic.
Stanislav Shkarin
openalex +6 more sources
Finite rank intermediate Hankel operators and the big Hankel operator [PDF]
International Journal of Mathematics and Mathematical Sciences, 2006 Let La2 be a Bergman space. We are interested in an intermediate Hankel operator HφM from La2 to a closed subspace M of L2 which is invariant under the multiplication by the coordinate function z.
Tomoko Osawa
doaj +3 more sources
On algebras of operators of finite rank
Journal of Functional Analysis, 1978 AbstractAlgebras of operators of finite rank are studied. Some structure theorems are presented. Results are used to study Banach representations of C∗-algebras and isolated points of the dual of C∗-algebras.
S.P Wang
openalex +3 more sources
Finite rank harmonic operator-valued functions
Linear Algebra and its Applications, 2001 AbstractThe purpose of this paper is to characterize when a harmonic function with values in the finite rank operators on a Hilbert space is expressible as a harmonic matrix-valued function. We show that harmonic function with values in the rank 1 normal operators is expressible as a harmonic matrix-valued function.
Laura Smithies
openalex +3 more sources
Riemannian geometry of finite rank positive operators [PDF]
Differential Geometry and its Applications, 2005 AbstractA riemannian metric is introduced in the infinite dimensional manifold Σn of positive operators with rank ...
Esteban Andruchow, Alejandro Varela
openalex +4 more sources
Finite rank Toeplitz operators on the Bergman space [PDF]
Proceedings of the American Mathematical Society, 2007 Given a complex Borel measure μ with compact support in the complex plane C the sesquilinear form defined on analytic polynomials f and g by B μ (f,g) = ∫fgdμ, determines an operator Tμ from the space of such polynomials P to the space of linear functionals on P. This operator is called the Toeplitz operator with symbol μ.
Daniel H. Luecking
openalex +2 more sources