Results 51 to 60 of about 19,389 (202)

Continuity bounds on the quantum relative entropy

, 2005
The quantum relative entropy is frequently used as a distance, or distinguishability measure between two quantum states. In this paper we study the relation between this measure and a number of other measures used for that purpose, including the trace ...
Bratteli O., Csiszar I., Jens Eisert, Koenraad M. R. Audenaert, Vedral V.   +4 more
core   +1 more source

An Optimal Preconditioned MINRES Method for Symmetrized Multilevel Block Toeplitz Systems With Applications

Numerical Linear Algebra with Applications, Volume 32, Issue 6, December 2025.
ABSTRACT In this work, we propose a novel preconditioned minimal residual method for a class of real, nonsymmetric multilevel block Toeplitz systems, which generalizes an ideal preconditioner established in [J. Pestana. Preconditioners for symmetrized Toeplitz and multilevel Toeplitz matrices. SIAM Journal on Matrix Analysis and Applications, 40(3):870–
Grigorios Tachyridis, Sean Y. Hon
wiley   +1 more source

Gruss inequality for some types of positive linear maps [PDF]

, 2014
Assuming a unitarily invariant norm $|||\cdot|||$ is given on a two-sided ideal of bounded linear operators acting on a separable Hilbert space, it induces some unitarily invariant norms $|||\cdot|||$ on matrix algebras $\mathcal{M}_n$ for all finite ...
Jagjit Singh, Matharu, Mohammad Sal Moslehian   +2 more
core  

Conformal optimization of eigenvalues on surfaces with symmetries

Journal of the London Mathematical Society, Volume 112, Issue 6, December 2025.
Abstract Given a conformal action of a discrete group on a Riemann surface, we study the maximization of Laplace and Steklov eigenvalues within a conformal class, considering metrics invariant under the group action. We establish natural conditions for the existence and regularity of maximizers. Our method simplifies the previously known techniques for
Denis Vinokurov
wiley   +1 more source

Least-Squares Approximation by Elements from Matrix Orbits Achieved by Gradient Flows on Compact Lie Groups

, 2008
Let $S(A)$ denote the orbit of a complex or real matrix $A$ under a certain equivalence relation such as unitary similarity, unitary equivalence, unitary congruences etc.
Li, C. K., Poon, Y. T., Schulte-Herbrueggen, T.   +2 more
core   +3 more sources

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
openaire   +1 more source

Boundary representations of locally compact hyperbolic groups

Proceedings of the London Mathematical Society, Volume 131, Issue 6, December 2025.
Abstract We develop the theory of Patterson–Sullivan measures for locally compact hyperbolic groups. This theory associates to certain left‐invariant metrics on the group measures on its boundary. Next, we establish irreducibility of the resulting (unitary) Koopman representations for second countable, nonelementary, unimodular locally compact ...
Michael Glasner
wiley   +1 more source

UNITARILY INVARIANT NORMS ON FINITE VON NEUMANN ALGEBRAS [PDF]

, 2018
John von Neumann’s 1937 characterization of unitarily invariant norms on the n × n matrices in terms of symmetric gauge norms on Cn had a huge impact on linear algebra. In 2008 his results were extended to Ifactor von Neumann algebras by J.
Fan, Haihui
core   +1 more source

Sensitivity of Perron and Fiedler Eigenpairs to Structural Perturbations of a Network

Numerical Linear Algebra with Applications, Volume 32, Issue 5, October 2025.
ABSTRACT One can estimate the change of the Perron and Fiedler values for a connected network when the weight of an edge is perturbed by analyzing relevant entries of the Perron and Fiedler vectors. This is helpful for identifying edges whose weight perturbation causes the largest change in the Perron and Fiedler values.
Silvia Noschese, Lothar Reichel
wiley   +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
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