Results 11 to 20 of about 136 (125)
Journal of Inequalities and Applications, 2020 In this article, we show unitarily invariant norm inequalities for sector 2 × 2 $2\times 2$ block matrices which extend and refine some recent results of Bourahli, Hirzallah, and Kittaneh (Positivity, 2020, https://doi.org/10.1007/s11117-020-00770-w ).
Xiaoying Zhou
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Some inequalities related to 2 × 2 $2\times 2$ block sector partial transpose matrices
Journal of Inequalities and Applications, 2020 In this article, two inequalities related to 2 × 2 $2\times 2$ block sector partial transpose matrices are proved, and we also present a unitarily invariant norm inequality for the Hua matrix which is sharper than an existing result.
Junjian Yang, Linzhang Lu, Zhen Chen
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A structure theorem for the polars of unitarily invariant norms [PDF]
Proceedings of the American Mathematical Society, 1985 The unitarily invariant norms of matrices, or operators, are essentially the symmetric norms of their singular values. A subclass of these norms depending upon only a few largest of the singular values is considered, and the polars of these norms are characterized. The result is then used to obtain generalizations of some well-known inequalities.
Mudholkar, Govind S., Freimer, Marshall
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Convex maps on $\protect \mathbb{R}^n$ and positive definite matrices
Comptes Rendus. Mathématique, 2020 We obtain several convexity statements involving positive definite matrices. In particular, if $A,B,X,Y$ are invertible matrices and $A,B$ are positive, we show that the map \[ (s,t) \mapsto \mathrm{Tr}\,\log \left(X^*A^sX + Y^*B^tY\right) \] is jointly ...
Bourin, Jean-Christophe, Shao, Jingjing
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Some inequalities for unitarily invariant norms [PDF]
Operators and Matrices, 2014 In this note, we use the convexity of the function φ(v) to sharpen the matrix version of the Heinz means, where φ(v) is defined as φ(v) = ‖AvXB1−v + A1−vXBv‖ on [0,1] for A,B,X ∈ Mn such that A and B are positive semidefinite, and also give a refinement of the inequality [Theorem 6, SIAM J. Matrix Anal. Appl.
Junliang Wu, Jianguo Zhao
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Heinz均值凸性的一个注记(A note on the convexity of the Heinz means)
Zhejiang Daxue xuebao. Lixue ban, 2013 Recently, KITTANEH obtained an improvement of the Heinz inequality for all unitarily invariant norms. In this note, we obtain a refinement of KITTANEH's result. We shall conclude this paper with some numerical examples.
ZOULi-min(邹黎敏)
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Monotonicity of unitarily invariant norms
Linear Algebra and its Applications, 2015 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Wang, Xue-Feng, Li, Ren-Cang
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Equalities and Inequalities for Norms of Block Imaginary Circulant Operator Matrices
Abstract and Applied Analysis, 2015 Circulant, block circulant-type matrices and operator norms have become effective tools in solving networked systems. In this paper, the block imaginary circulant operator matrices are discussed.
Xiaoyu Jiang, Kicheon Hong
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On some inequalities for unitarily invariant norms [PDF]
Journal of Mathematical Inequalities, 2013 In this paper, we present several inequalities for unitarily invariant norms by using the convexity of the function g(r )= A r XB 2−r +A 2−r XB r on the interval (0,2). Our results are refinements of some existing inequalities.
Xiaohui Fu, Chuanjiang He
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Non-commutative Clarkson inequalities for unitarily invariant norms [PDF]
Pacific Journal of Mathematics, 2002 The authors obtain two types of norm inequalities which are extensions of the classical Clarkson inequalities for the Schatten \(p\)-norms in [\textit{C. A. McCarthy}, Isr. J. Math. 5, 249--271 (1967; Zbl 0156.37902)]. The authors show these inequalities by using operator convex and concave functions.
Hirzallah, Omar, Kittaneh, Fuad
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