Results 11 to 20 of about 10,518 (235)
Operators with commutative commutants.
Michigan Mathematical Journal, 1988 Given operators M and N on a Hilbert space H, suppose that M (resp. N) is the direct sum of k (resp. n) copies of an operator A having a commutative commutant. Suppose further that m and k are countable cardinalities (or, any cardinalities if H is separable) and that N is a quasi-affine transform of M (i.e., \(NX=XM\) for some injective operator X with
Radjabalipour, M., Radjavi, H.
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A Characterization of Central BMO Space via the Commutator of Fractional Hardy Operator
Journal of Function Spaces, 2020 This paper is devoted in characterizing the central BMO ℝn space via the commutator of the fractional Hardy operator with rough kernel. Precisely, by a more explicit decomposition of the operator and the kernel function, we will show that if the symbol ...
Lei Zhang, Shaoguang Shi
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Making Almost Commuting Matrices Commute [PDF]
Communications in Mathematical Physics, 2009 Suppose two Hermitian matrices $A,B$ almost commute ($\Vert [A,B] \Vert \leq $). Are they close to a commuting pair of Hermitian matrices, $A',B'$, with $\Vert A-A' \Vert,\Vert B-B'\Vert \leq $? A theorem of H. Lin shows that this is uniformly true, in that for every $ >0$ there exists a $ >0$, independent of the size $N$ of the matrices ...
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Some Notes on Relative Commutators
InPrime, 2020 Let G be a group and α ϵ Aut(G). An α-commutator of elements x, y ϵ G is defined as [x, y]α = x-1y-1xyα. In 2015, Barzegar et al. introduced an α-commutator of elements of G and defined a new generalization of nilpotent groups by using the definition of
Masoumeh Ganjali, Ahmad Erfanian
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Proceedings of the American Mathematical Society, 1987 Let R R be a principal ideal ring and M k , n {M_{k,n}} the set of k × n k \times n matrices over R R . The following statments are proved: (a) If k ≤ n
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SOLVABILITY OF FREE PRODUCTS, CAYLEY GRAPHS AND COMPLEXES [PDF]
Journal of Algebraic Systems, 2013 In this paper, we verify the solvability of free product of finite cyclic groups with topological methods. We use Cayley graphs and Everitt methods to construct suitable 2-complexes corresponding to the presentations of groups and their commutator ...
Hanieh Mirebrahimi, Fatemeh Ghanei
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Commutation matrices and Commutation tensors [PDF]
Linear and Multilinear Algebra, 2018 The commutation matrix was first introduced in statistics as a transposition matrix by Murnaghan in 1938. In this paper, we first investigate the commutation matrix which is employed to transform a matrix into its transpose. We then extend the concept of the commutation matrix to commutation tensor and use the commutation tensor to achieve the ...
Changqing Xu, Lingling He, Zerong Lin
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Bulletin of the Australian Mathematical Society, 2006 A ring is called a commutator ring if every element is a sum of additive commutators. In this note we give examples of such rings. In particular, we show that given any ring R, a right R-module N, and a nonempty set Ω, EndR(⌖ΩN) and EndR(ΠΩN) are commutator rings if and only if either Ω is infinite or EndR(N) is itself a commutator ring.
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Commutant lifting for commuting row contractions [PDF]
Bulletin of the London Mathematical Society, 2010 one section and references were ...
Davidson, Kenneth R., Le, Trieu
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Weighted Estimates for Maximal Commutators of Multilinear Singular Integrals
Journal of Function Spaces and Applications, 2012 This paper is concerned with the pointwise estimates for the sharp function of the maximal multilinear commutators TΣb* and maximal iterated commutator TΠb*, generalized by m-linear operator T and a weighted Lipschitz function b.
Dongxiang Chen, Suzhen Mao
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