Results 31 to 40 of about 783,766 (273)

On Some Matrix Trace Inequalities

Journal of Inequalities and Applications, 2010
We first present an inequality for the Frobenius norm of the Hadamard product of two any square matrices and positive semidefinite matrices. Then, we obtain a trace inequality for products of two positive semidefinite block matrices by using 2×2 ...
Ramazan Türkmen, Zübeyde Ulukök   +1 more
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Geometric Inequalities in Normed Spaces

Rocky Mountain Journal of Mathematics, 1992
Let \(x\) be a \(T\)-periodic solution of \(x'= f(x)\), where \(f: E\to E\) is Lipschitz continuous with constant \(L\) and \(E\) is a Banach space. In [the first author, \textit{D. Fisher} and the second author, Proc. Am. Math. Soc. 98, 376-378 (1986; Zbl 0632.34048)] it is shown that \(TL\geq 6\); this inequality is optimal [cf.
Busenberg, S., Martelli, M.
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Simple Norm Inequalities

The American Mathematical Monthly, 2006
(2006). Simple Norm Inequalities. The American Mathematical Monthly: Vol. 113, No. 3, pp. 256-260.
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On a conjecture of the norm Schwarz inequality [PDF]

Annals of Functional Analysis, 2017
For any positive invertible matrix $A$ and any normal matrix $B$ in $M_{n}({\Bbb C})$, we investigate whether the inequality $ ||A\sharp (B^{*}A^{-1}B)||\geq ||B|| $ is true or not, where $\sharp$ denotes the geometric mean and $||\cdot||$ denotes the operator norm. We will solve this problem negatively. The related topics are also discussed.
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Weighted Norm Inequalities for Multipliers [PDF]

Proceedings of the American Mathematical Society, 1988
We consider the two-weight function problem for a class of multiplier operators that include the Riesz and Bessel potentials.
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Several Matrix Euclidean Norm Inequalities Involving Kantorovich Inequality

Journal of Inequalities and Applications, 2009
Kantorovich inequality is a very useful tool to study the inefficiency of the ordinary least-squares estimate with one regressor. When regressors are more than one statisticians have to extend it.
Wang Litong, Yang Hu
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On a Norm Inequality for Three 2 × 2 Matrices with One Normal Factor

Mathematics
In this paper, we continue to investigate the norm inequality for three real matrices that was recently conjectured by L. László. We establish the validity of the conjecture for the case where n=2 and one of the matrices is normal.
Na Li, Fen Wang
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Isoperimetric Inequalities in Normed Planes

, 2020
The classical isoperimetric inequality can be extended to a general normed plane. In the Euclidean plane, the defect in the isoperimetric inequality can be calculated in terms of the signed areas of some singular sets. In this paper we consider normed planes with smooth by parts unit balls and the corresponding class of admissible curves.
dos Santos, Rafael S., Craizer, Marcos
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A norm inequality for three matrices

The Electronic Journal of Linear Algebra, 2022
We prove a Frobenius norm inequality for three matrices, analogous to the well-known Bottcher--Wenzel inequality. The situation is also similar: standard inequalities would yield an upper bound, which however can be reduced by means of further, detailed investigations.
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Another Converse of Jensen's Inequality [PDF]

, 2009
We give the best possible global bounds for a form of discrete Jensen’s inequality.
Simic, Slavko
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