Results 21 to 30 of about 136 (125)

Positivity of partitioned Hermitian matrices with unitarily invariant norms [PDF]

Positivity, 2014
6 ...
Li, Chi Kwong, Zhang, Fuzhen
openaire   +4 more sources

Unitarily invariant norm inequalities for matrix means [PDF]

The Journal of Analysis, 2021
AbstractThe main target of this article is to present several unitarily invariant norm inequalities which are refinements of arithmetic-geometric mean, Heinz and Cauchy-Schwartz inequalities by convexity of some special functions.
Zuo, Hongliang, Jiang, Fazhen
openaire   +2 more sources

Submultiplicativity vs subadditivity for unitarily invariant norms

Linear Algebra and its Applications, 2004
The authors prove that if \(A\) and \(B\) are two \(n\)-by-\(n\) nonzero positive semidefinite matrices and \(\|\cdot\|\) is a unitarily invariant norm on matrices satisfying \(\|\text{diag}(1,0,\dots, 0)\|\geq 1\), then the inequalities \[ {\| AB\|\over\| A\|\,\| B\|}\leq {\| A+ B\|\over\| A\|+\| B\|}\quad\text{and}\quad {\| A\circ B\|\over \| A\|\,\|
Hiai, Fumio, Zhan, Xingzhi
openaire   +2 more sources

Volume ratio, sparsity, and minimaxity under unitarily invariant norms [PDF]

2013 IEEE International Symposium on Information Theory, 2013
The current paper presents a novel machinery for studying non-asymptotic minimax estimation of high-dimensional matrices, which yields tight minimax rates for a large collection of loss functions in a variety of problems. Based on the convex geometry of finite-dimensional Banach spaces, we first develop a volume ratio approach for determining minimax ...
Zongming Ma, Yihong Wu 0001
openaire   +3 more sources

Some inequalities for unitarily invariant norms [PDF]

Journal of Mathematical Inequalities, 2012
This paper aims to present some inequalities for unitarily invariant norms. In section 2, we give a refinement of the Cauchy-Schwarz inequality for matrices. In section 3, we obtain an improvement for the result of Bhatia and Kittaneh (Linear Algebra Appl. 308 (2000) 203-211).
openaire   +1 more source

Operator Monotone Functions and Convexity of Its Derivatives Norms

پژوهش‌های ریاضی, 2021
Introduction  Given the important role convex and quasi-convex functions play in many areas of mathematics and especially in optimization, one of the inequalities that has attracted the attention of many mathematicians in recent decades is Hermit ...
Zahra Rahimi Chegeni, amir ghasem ghazanfari, Kamal Falahi   +2 more
doaj  

Some inequalities for unitarily invariant norm

Linear Algebra and its Applications, 2012
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Matharu, Jagjit Singh, Aujla, Jaspal Singh   +1 more
openaire   +1 more source

Unitarily invariant norm inequalities for operators

Journal of the Egyptian Mathematical Society, 2012
10 pages, Accepted ...
Erfanian Omidvar, M., Moslehian, M.S., Niknam, A.   +2 more
openaire   +2 more sources

Kernel Bounds for Parabolic Operators Having First‐Order Degeneracy at the Boundary

Mathematische Nachrichten, EarlyView.
ABSTRACT We study kernel estimates for parabolic problems governed by singular elliptic operators ∑i,j=1N+1qijDij+cDyy,cγ+1>0,γ=qN+1,N+1,$$\begin{equation*} \sum _{i,j=1}^{N+1}q_{ij}D_{ij}+c\frac{D_y}{y},\qquad \frac{c}{\gamma }+1>0, \quad \gamma =q_{N+1,N+1}, \end{equation*}$$in the half‐space R+N+1={(x,y):x∈RN,y>0}$\mathbb {R}^{N+1}_+=\lbrace (x,y ...
L. Negro, C. Spina
wiley   +1 more source

Local Lidskii's theorems for unitarily invariant norms [PDF]

Linear Algebra and its Applications, 2018
arXiv admin note: text overlap with arXiv:1610 ...
Massey, Pedro Gustavo, Rios, Noelia Belén, Stojanoff, Demetrio   +2 more
openaire   +4 more sources