Results 21 to 30 of about 4,469,777 (359)
A hyperbolic universal operator commuting with a compact operator [PDF]
, 2019 A Hilbert space operator is called universal (in the sense of Rota) if every operator on the Hilbert space is similar to a multiple of the restriction of the universal operator to one of its invariant subspaces.
Cowen, Carl C. +1 more
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Composite operators in QCD [PDF]
Nuclear Physics B, 1992 We give a formula for the derivatives of a correlation function of composite operators with respect to the parameters (i.e., the strong fine structure constant and the quark mass) of QCD in four-dimensional euclidean space. The formula is given as spatial integration of the operator conjugate to a parameter. The operator product of a composite operator
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A Novel Reliability Analysis Method for Fuzzy Multi-State Systems Considering Correlation
IEEE Access, 2019 Fuzzy multi-state systems (FMSSs) exist widely in practical engineering. It is usually difficult to evaluate the reliability of FMSSs because the reliability data is usually fuzzy due to the inaccuracy or imperfection of information, and there is often ...
Huiying Gao, Xiaoqiang Zhang
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An approach to elliptic equations with nonlinear gradient terms via a modulation framework
Bulletin of Mathematical Sciences, 2023 We consider a class of nonhomogeneous elliptic equations with fractional Laplacian and nonlinear gradient terms, namely [Formula: see text] in [Formula: see text], where [Formula: see text], [Formula: see text] is the nonlinearity, [Formula: see text ...
Lucas C. F. Ferreira, Wender S. Lagoin
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Universal Sequences of Composition Operators
The Journal of Geometric Analysis, 2023 Let $G$ and $ $ be two planar domains. We give necessary and sufficient conditions on a sequence $( _n)$ of eventually injective holomorphic mappings from $G$ to $ $ for the existence of a function $f\in H( )$ whose orbit under the composition by $( _n)$ is dense in $H(G)$.
Charpentier, S., Mouze, Augustin
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2-Complex Symmetric Composition Operators on H2
Axioms, 2022 In this paper, we study 2-complex symmetric composition operators with the conjugation J, defined by Jf(z)=(f(z¯))¯, on the Hardy space H2. More precisely, we obtain the necessary and sufficient condition for the composition operator Cϕ to be 2-complex ...
Lian Hu, Songxiao Li, Rong Yang
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A note on weighted bounds for rough singular integrals [PDF]
, 2017 We show that the $L^2(w)$ operator norm of the composition $M\!\circ T_{\Omega}$, where $M$ is the maximal operator and $T_{\Omega}$ is a rough homogeneous singular integral with angular part $\Omega\in L^{\infty}(S^{n-1})$, depends quadratically on $[w ...
Lerner, Andrei K.
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Local spectral theory of endomorphisms of the disk algebra
Demonstratio Mathematica, 2016 Let A(𝔻) denote the disk algebra. Every endomorphism of A(𝔻) is induced by some ϕ ∈ A(𝔻) with ‖ϕ‖ ≤ 1. In this paper, it is shown that if ϕ is not an automorphism of 𝔻 and ϕ has a fixed point in the open unit disk then the endomorphism induced by ϕ is ...
Trivedi Shailesh, Chandra Harish
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Skew-symmetric and essentially unitary operators via Berezin symbols
Open Mathematics, 2020 We characterize skew-symmetric operators on a reproducing kernel Hilbert space in terms of their Berezin symbols. The solution of some operator equations with skew-symmetric operators is studied in terms of Berezin symbols.
Altwaijry Najla +3 more
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Norms of a Product of Integral and Composition Operators between Some Bloch-Type Spaces
Axioms, 2023 We present some formulas for the norm, as well as the essential norm, of a product of composition and an integral operator between some Bloch-type spaces of analytic functions on the unit ball, in terms of given symbols and weights.
Stevo Stević
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