Results 81 to 90 of about 19,389 (202)
Some operator inequalities for unitarily invariant norms
Annals of Functional Analysis, 2017 This note aims to present some operator inequalities for unitarily invariant norms. First, a Zhan-type inequality for unitarily invariant norms is given. Moreover, some operator inequalities for the Cauchy–Schwarz type are also established.
Zhao, Jianguo, Wu, Junliang
openaire +2 more sources
Angle‐Free Cluster‐Robust Ritz Value Bounds for Restarted Block Eigensolvers
Numerical Linear Algebra with Applications, Volume 32, Issue 1, February 2025.ABSTRACT Convergence rates of block iterations for solving Hermitian eigenvalue problems typically measure the errors of Ritz values approximating eigenvalues. These errors are usually bounded in terms of principal angles between the initial or iterative subspace and the invariant subspace associated with the target eigenvalues.
Ming Zhou, Andrew Knyazev, Klaus Neymeyr
wiley +1 more source
Advanced Quantum Technologies, Volume 8, Issue 2, February 2025.The UAVQD vectorization method is demonstrated to effectively address various quantum system challenges. From simple quantum information models to the dynamics of the biological FMO complex, and Dicke superradiance, this method achieves efficient, scalable simulation with promising implications for advanced quantum computing.
Saurabh Shivpuje +4 more
wiley +1 more source
On perturbations of the isometric semigroup of shifts on the semiaxis [PDF]
, 2012 We study perturbations $(\tilde\tau_t)_{t\ge 0}$ of the semigroup of shifts $(\tau_t)_{t\ge 0}$ on $L^2(\R_+)$ with the property that $\tilde\tau_t - \tau_t$ belongs to a certain Schatten-von Neumann class $\gS_p$ with $p\ge 1$.
Amosov, G. G. +2 more
core
Linear independence of coherent systems associated to discrete subgroups
Bulletin of the London Mathematical Society, Volume 57, Issue 2, Page 315-329, February 2025.Abstract This note considers the finite linear independence of coherent systems associated to discrete subgroups. We show by simple arguments that such coherent systems of amenable groups are linearly independent whenever the associated twisted group ring does not contain any nontrivial zero divisors.
Ulrik Enstad, Jordy Timo van Velthoven
wiley +1 more source
An Algebraic Approach to Light–Matter Interactions
Advanced Physics Research, Volume 4, Issue 1, January 2025.This is a review of an algebraic approach to light–matter interactions that is theoretically powerful and computationally friendly. Theoretical expressions can be developed and manipulated conveniently thanks to the generality of the basis on which the approach rests, and a compact notation.
Ivan Fernandez‐Corbaton
wiley +1 more source
Singular value inequalities of matrices via increasing functions
Journal of Inequalities and ApplicationsLet A, B, X, and Y be n × n $n\times n$ complex matrices such that A is self-adjoint, B ≥ 0 $B\geq 0$ , ± A ≤ B $\pm A\leq B$ , max ( ∥ X ∥ 2 , ∥ Y ∥ 2 ) ≤ 1 $\max ( \Vert X \Vert ^{2}, \Vert Y \Vert ^{2} ) \leq 1$ , and let f be a nonnegative increasing
Wasim Audeh +3 more
doaj +1 more source
Schur-multiplicative maps preserving unitarily invariant norms
Linear Algebra and its Applications, 2008 Let \(\|{\cdot}\| \) be a given unitary invariant norm on rectangular \(m\)-by-\(n\) matrices, and let \(A\circ B\) be the Schur (=\,entrywise) product of matrices. The author classifies \(\|{\cdot}\| \)-isometries \(\Phi:M_{m\times n}\to M_{m\times n}\) which are Schur multiplicative, that is, which satisfy \(\| \Phi(A)\| =\| A\| \) and \(\Phi(A\circ ...
openaire +1 more source
Matrix semigroups determined by unitarily invariant norms
Linear Algebra and its Applications, 1974 AbstractThe purpose of this paper is to study the structure of the matrix semigroups defined by unitarily invariant norms and, equivalently, those defined by arbitrary ellipsoidal norms. Among other things it is found that when an element of such a semigroup has a semi-inverse, the semi-inverse is unique, and, in the case of unitarily invariant norms ...
openaire +2 more sources
Inequalities for unitarily invariant norms [PDF]
Journal of Mathematical Inequalities, 2012 Limin Zou, Youyi Jiang
openaire +1 more source