Results 21 to 30 of about 3,164,915 (295)

A Characterization on Singular Value Inequalities of Matrices

Journal of Function Spaces, 2020
We obtain a characterization of pair matrices A and B of order n such that sjA≤sjB, j=1, …, n, where sjX denotes the j-th largest singular values of X. It can imply not only some well-known singular value inequalities for sums and direct sums of matrices
Wei Dai, Yongsheng Ye
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Direct sums of J-rings and radical rings

International Journal of Mathematics and Mathematical Sciences, 1995
Let R be a ring, J(R) the Jacobson radical of R and P the set of potent elements of R. We prove that if R satisfies (∗) given x, y in R there exist integers m=m(x,y)>1 and n=n(x,y)>1 such that xmy=xyn and if each x∈R is the sum of a potent element and a ...
Xiuzhan Guo
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Continuous refinements of some Jensen-type inequalities via strong convexity with applications

Journal of Inequalities and Applications, 2022
In this paper we prove new continuous refinements of some Jensen type inequalities in both direct and reversed forms. As applications we also derive some continuous refinements of Hermite–Hadamard, Hölder, and Popoviciu type inequalities.
Ludmila Nikolova, Lars-Erik Persson, Sanja Varošanec   +2 more
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Spectrum of the Direct Sum of Operators

Electronic Journal of Differential Equations, 2011
In this work, a connection between some spectral properties of direct sum of operators in the direct sum of Hilbert spaces and its coordinate operators has been investigated.
Elif Otkun Cevik, Zameddin I. Ismailov
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On direct sums of reductive operators [PDF]

Proceedings of the American Mathematical Society, 1974
An example is given to show that the direct sum of two (distinct) reductive operators need not be reductive. The conjecture that A ⊕
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On Direct Sums of Reflexive Operators [PDF]

Proceedings of the American Mathematical Society, 1976
Let A 1 {A_1}
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Geometric Properties of Infinite Direct Sums

Mathematics
We show exactly when the topology of convergence in measure in Banach ideal spaces is linear (equivalently, coarser than the norm topology). Next, we present the relationship between the Kadets–Klee and suitable monotonicity properties with respect to ...
Paweł Kolwicz
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Relative injectivity and CS-modules

International Journal of Mathematics and Mathematical Sciences, 1994
In this paper we show that a direct decomposition of modules M⊕N, with N homologically independent to the injective hull of M, is a CS-module if and only if N is injective relative to M and both of M and N are CS-modules. As an application, we prove that
Mahmoud Ahmed Kamal
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Computing direct sum decompositions

Journal of Symbolic Computation
We describe and prove correctness of two practical algorithms for finding indecomposable summands of finitely generated modules over a finitely generated k-algebra R. The first algorithm applies in the (multi)graded case, which enables the computation of indecomposable summands of coherent sheaves on subvarieties of toric varieties (in particular, for ...
Devlin Mallory, Mahrud Sayrafi
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DIRECT SUMS OF INFINITELY MANY KERNELS [PDF]

Journal of the Australian Mathematical Society, 2010
AbstractLet 𝒦 be the class of all rightR-modules that are kernels of nonzero homomorphisms φ:E1→E2for some pair of indecomposable injective rightR-modulesE1,E2. In a previous paper, we completely characterized when two direct sumsA1⊕⋯⊕AnandB1⊕⋯⊕Bmof finitely many modulesAiand Bjin 𝒦 are isomorphic.
ECEVIT S, FACCHINI, ALBERTO, KOSAN M. T.
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