Results 1 to 10 of about 554 (59)
Multivariable sub-Hardy Hilbert spaces invariant under the action of n-tuple of finite Blaschke factors [PDF]
Journal of Mathematical Analysis and Applications, 2021 This paper deals with representing in concrete fashion those Hilbert spaces that are vector subspaces of the Hardy spacesH(D) (1 ≤ p ≤ ∞) that remain invariant under the action of coordinate wise multiplication by an n-tuple (TB1 , . . .
S. Lata, Sushant Pokhriyal, Dinesh Singh
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Analytic extension of n-normal operators
Operators and Matrices, 2021 Normal operators and n -normal operators played a pivotal role in the development of operator theory. In order to generalize these classes of operators, we introduce new classes of operators which we call analytic extension of n normal operator and F ...
S. Mécheri
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The transfer ideal under the action of orthogonal group in modular case
Open Mathematics, 2022 In this paper, we study the structures of the invariant subspaces under the action of orthogonal group O2ν(Fq,S){O}_{2\nu }\left({F}_{q},S). In particular, we give a detailed description of 2-codimensional invariant subspaces.
Lingli Zeng
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A note on the structure of normal Hamiltonian matrices
Operators and Matrices, 2021 The structures of the blocks of a normal Hamiltonian matrix are studied. In this note it is obtained that all four blocks of a normal Hamiltonian matrix H = [ A B C −A∗ ] can be expressed as linear combinations of four other matrices. Mathematics subject
C. Chorianopoulos
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Linear isomorphic spaces of fractional-order difference operators
Alexandria Engineering Journal, 2021 In the present paper, we intend to make an approach to introduce and study the applications of fractional-order difference operators by generating Orlicz almost null and almost convergent sequence spaces.
S.A. Mohiuddine +3 more
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Applications of fixed point theorems in the theory of invariant subspaces [PDF]
Fixed Point Theory and Applications, 2012 We survey several applications of fixed point theorems in the theory of invariant subspaces. The general idea is that a fixed point theorem applied to a suitable map yields the existence of invariant subspaces for an operator on a Banach space.MSC:47A15,
Rafa Esṕınola, M. Lacruz
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Almost convergence and generalized weighted mean II
Journal of Inequalities and Applications, 2014 In this paper, we investigate some new sequence spaces, which naturally emerge from the concepts of almost convergence and generalized weighted mean.
M. Kirişci
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On the class of n-power D-m-quasi-normal operators on Hilbert spaces
, 2020 As a continuation of our previous work [22], this paper is devoted to the study for further properties of the class of (n,m) -power D -normal operators( [(n,m)DN] ) and introduce some classes of operators on Hilbert space called D -m -quasi-normal ...
Beinane Sid Ahmed, S. Mahmoud
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The invariant subspaces of S ⊕ S*
Concrete Operators, 2020 Using the tools of Sz.-Nagy–Foias theory of contractions, we describe in detail the invariant subspaces of the operator S ⊕ S*, where S is the unilateral shift on a Hilbert space. This answers a question of Câmara and Ross.
Timotin Dan
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On the classes of (n,m)-power D-normal and (n,m)-power D-quasi-normal operators
Operators and Matrices, 2019 This paper is devoted to the study of some new classes of operators on Hilbert space called (n,m) -power D -normal ( [(n,m)DN] ) and (n,m) -power D -quasi-normal ( [(n,m)DQN] ) , associated with a Drazin invertible operator using its Drazin inverse. Some
S. Mahmoud, O. Ahmed
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