Results 11 to 20 of about 554 (59)
On some nonlinear parabolic equations with variable exponents and measure data
Moroccan Journal of Pure and Applied Analysis, 2020 We prove the existence of renormalized solutions to a class of nonlinear evolution equations, supplemented with initial and Dirichlet condition in the framework of generalized Sobolev spaces. The data are assumed merely integrable.
Hamdaoui Bouchra El, Bennouna Jaouad
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Proper contractions and invariant subspaces
International Journal of Mathematics and Mathematical Sciences, Volume 28, Issue 4, Page 223-230, 2001., 2001 Let T be a contraction and A the strong limit of {T∗nTn}n ≥ 1. We prove the following theorem: if a hyponormal contraction T does not have a nontrivial invariant subspace, then T is either a proper contraction of class 𝒞00 or a nonstrict proper contraction of class 𝒞10 for which A is a completely nonprojective nonstrict proper contraction.
C. S. Kubrusly, N. Levan
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Weighted conditional expectation operators
, 2011 This paper presents the fundamental operator-theoretic properties of products of conditional expectation and multiplication operators. It is shown that boundedness of such a product need not depend on the boundedness of the multiplication operator.
J. D. Herron
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Some remarks on the invariant subspace problem for hyponormal operators
International Journal of Mathematics and Mathematical Sciences, Volume 28, Issue 6, Page 359-365, 2001., 2001 We make some remarks concerning the invariant subspace problem for hyponormal operators. In particular, we bring together various hypotheses that must hold for a hyponormal operator without nontrivial invariant subspaces, and we discuss the existence of such operators.
Vasile Lauric
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Somewhere Dense Orbit that is not Dense on a Complex Hilbert Space
Concrete Operators, 2019 In this paper, we present the existence of n-tuple of operators on complex Hilbert space that has a somewhere dense orbit and is not dense. We give the solution to the question stated in [11]: “Is there n-tuple of operators on a complex Hilbert space ...
Wilberth Neema +2 more
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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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Hyperinvariant subspaces for some operators on locally convex spaces
International Journal of Mathematics and Mathematical Sciences, Volume 23, Issue 12, Page 807-814, 2000., 2000 Some results concerning hyperinvariant subspaces of some operators on locally convex spaces are considered. Denseness of a class of operators which have a hyperinvariant subspace in the algebra of locally bounded operators is proved.
Edvard Kramar
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Cohyponormal operators with the single valued extension property
International Journal of Mathematics and Mathematical Sciences, Volume 9, Issue 4, Page 659-663, 1986., 1986 It is proved that in order to find a nontrivial hyperinvariant subspace for a cohyponormal operator it suffices to make the further assumption that the operator have the single‐valued extension property.
Ridgley Lange, Shengwang Wang
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, 2012 Let k be an algebraically closed field and α, β, γ be partitions. An algebraic group acts on the constructible set of short exact sequences of nilpotent k-linear operators of Jordan types α, β, and γ, respectively; we are interested in the stratification
J. Kosakowska, M. Schmidmeier
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A few results on some nonlinear parabolic problems in Orlicz-Sobolev spaces
Moroccan Journal of Pure and Applied Analysis, 2018 In this paper, we present our results (see our papers), which concern the existence of the renormalized solutions for equations of the type:
Redwane Hicham
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