Results 31 to 40 of about 858,067 (279)
Weighted composition operators between spaces of Dirichlet type [PDF]
, 2009 In this work we characterize boundedness and compactness of weighted composition operators acting between Dirichlet type spaces by using Carleson measures.
Kumar, Sanjay
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Corrigendum to: Essential normality, essential norms and hyperrigidity
, 2015 In our paper "Essential normality, essential norms and hyperrigidity" we claimed that the restriction of the identity representation of a certain operator system (constructed from a polynomial ideal) has the unique extension property, however the justification we gave was insufficient.
Kennedy, Matthew, Shalit, Orr
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Essential norm of the differential operator [PDF]
Operators and Matrices, 2019 This paper is a follow-up contribution to our work [10] where we studied some spectral properties of the differential operator $D$ acting between generalized Fock spaces $\mathcal{F}_{(m,p)}$ and $\mathcal{F}_{(m,q)}$ when both exponents $p$ and $q$ are finite.
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Weighted composition operators between different Fock spaces
, 2017 We study weighted composition operators acting between Fock spaces. The following results are obtained: (1) Criteria for the boundedness and compactness; (2) Characterizations of compact differences and essential norm; (3) Complete descriptions of path ...
Khoi, Le Hai, Tien, Pham Trong
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MathematicsIn this work, we characterize the boundedness of t-generalized composition operators from F(p, q, s) spaces to iterated weighted-type Banach space. We also provide estimates of the norm and the essential norm of t-generalized composition operators from F(
Shams Alyusof, Nacir Hmidouch
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Trapped modes in finite quantum waveguides
, 2011 The Laplace operator in infinite quantum waveguides (e.g., a bent strip or a twisted tube) often has a point-like eigenvalue below the essential spectrum that corresponds to a trapped eigenmode of finite L2 norm.
Delitsyn, Andrey L. +2 more
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The essential norms of composition operators [PDF]
Glasgow Mathematical Journal, 1992 Throughout the paper n denotes a fixed positive integer unless otherwise specified. Let B = Bn denote the open unit ball of ℂn and let S = Sn denote its boundary, the unit sphere. The unique rotation-invariant probability measure on 5 will be denoted by σ = σn. For n = l, we use more customary notations D = B1, T = S1 and dσ1= dθ/2π. The Hardy space on
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Condition for emergence of complex eigenvalues in the Bogoliubov-de Gennes equations
, 2008 The condition for the appearance of dynamical instability of the Bose-condensed system, characterized by the emergence of complex eigenvalues in the Bogoliubov-de Gennes equations, is studied analytically.
L. Pitaevskii +6 more
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The essential norm of multiplication operators on $$L_p(\mu )$$
Afrika Matematika, 2022 AbstractWe show that the formula for the essential norm of a multiplication operator on$$L_p$$Lp, for$$1<p<\infty $$1<p<∞, also holds for$$p=1$$p=1. We also provide a proof for the formula which works simultaneously for all$$p\in [1,\infty )$$p∈[1,∞).
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Pediatric Blood &Cancer, EarlyView.ABSTRACT Purpose Retinoblastoma (RB) is the most common pediatric ocular cancer, yet population‐based data on survival and risk factors remain limited. This study aimed to describe survival in a large national RB cohort and identify predictors of death and complications.
Samuel Sassine +14 more
wiley +1 more source