Results 11 to 20 of about 211,713 (326)
Continuity of Multiplication in Operator Algebras [PDF]
Proceedings of the American Mathematical Society, 1955 Parts of Banach algebra theory have been generalized recently [2; 1 ] to multiplicatively convex topological algebras. An important class of examples of Banach algebras is the class of subalgebras of the algebra of continuous linear transformations on a Banach space.
Alexander Blair
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Cyclic vectors for multiplication operators. [PDF]
Michigan Mathematical Journal, 1988 If \(E\) is a complex topological vector space and \(T\) a continuous linear transformation on \(E\), a vector \(x\in E\) is a cyclic vector for \(T\) if \(\{p(T)x: p\) a polynomial\(\}\) is dense in \(E\). If \(\mu\) is a compactly supported Borel measure on \(\mathbb C\), let \(X\) be the closed unit ball of \(L^{\infty}(\mu)\) and let \(X_ p\) be ...
Allen Shields
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Extrapolation of operator-valued multiplication operators [PDF]
Quaestiones Mathematicae, 2021 We discuss $\mathrm{L}^p$ fiber spaces which appear, e.g., as extrapolation spaces of unbounded multiplication operators which in turn are motivated, for instance, by non-autonomous evolution equations.
Christian Budde, Retha Heymann
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On multiplicativity of the Bernstein operator
Computers & Mathematics with Applications, 2011 AbstractFor continuous functions f and g, we prove that the Bernstein operator Bn is multiplicative for all n≥1 and all x∈2[0,1] if and only if at least one of the functions f and g is a constant function. Some other variants of multiplicativity are also considered.
Gancho Tachev
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Multiplicative forms and Spencer operators [PDF]
Mathematische Zeitschrift, 2014 Motivated by our attempt to recast Cartan's work on Lie pseudogroups in a more global and modern language, we are brought back to the question of understanding the linearization of multiplicative forms on groupoids and the corresponding integrability problem.
Marius Crainic +2 more
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Multiplicative preservers and induced operators
Linear Algebra and its Applications, 2004 The study of symmetry classes of tensors is motivated by many branches of pure and applied mathematics, combinatorial theory, matrix theory, operator theory, group representation theory, differential geometry, partial differential equations, quantum mechanics and other areas.
Wai-Shun Cheung +2 more
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Israel Journal of Mathematics, 2015 For functions of a single complex variable, points of multiplicity greater than $k$ are characterized by the vanishing of the first $k$ derivatives. There are various quantitative generalizations of this statement, showing that for functions that are in some sense close to having multiplicity greater than $k$, the first $k$ derivatives must be small ...
Binyamini, Gal, Novikov, Dmitry
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Multiples of hypercyclic operators [PDF]
Proceedings of the American Mathematical Society, 2008 We give a negative answer to a question of Prăjitură by showing that there exists an invertible bilateral weighted shift T T on ℓ 2 ( Z ) \ell _2(\mathbb {Z}) such that T T and 3 T 3T are ...
Badea, Catalin +2 more
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Data‐driven performance metrics for neural network learning
International Journal of Adaptive Control and Signal Processing, EarlyView., 2023 Summary Effectiveness of data‐driven neural learning in terms of both local mimima trapping and convergence rate is addressed. Such issues are investigated in a case study involving the training of one‐hidden‐layer feedforward neural networks with the extended Kalman filter, which reduces the search for the optimal network parameters to a state ...
Angelo Alessandri +2 more
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On Some Properties of Cowen-Douglas Class of Operators
Journal of Function Spaces, 2018 We will consider multiplication operators on a Hilbert space of analytic functions on a domain Ω⊂C. For a bounded analytic function φ on Ω, we will give necessary and sufficient conditions under which the complement of the essential spectrum of Mφ in φΩ ...
Parastoo Heiatian Naeini +1 more
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