Results 81 to 90 of about 10,743 (170)

Sparse graph signals – uncertainty principles and recovery

GAMM-Mitteilungen, Volume 48, Issue 2, June 2025.
ABSTRACT We study signals that are sparse either on the vertices of a graph or in the graph spectral domain. Recent results on the algebraic properties of random integer matrices as well as on the boundedness of eigenvectors of random matrices imply two types of support size uncertainty principles for graph signals.
Tarek Emmrich, Martina Juhnke, Stefan Kunis   +2 more
wiley   +1 more source

Singular value inequalities of matrices via increasing functions

Journal of Inequalities and Applications
Let 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, Anwar Al-Boustanji, Manal Al-Labadi, Raja’a Al-Naimi   +3 more
doaj   +1 more source

On the stability of Runge–Kutta methods for arbitrarily large systems of ODEs

Communications on Pure and Applied Mathematics, Volume 78, Issue 4, Page 821-855, April 2025.
Abstract We prove that Runge–Kutta (RK) methods for numerical integration of arbitrarily large systems of Ordinary Differential Equations are linearly stable. Standard stability arguments—based on spectral analysis, resolvent condition or strong stability, fail to secure the stability of RK methods for arbitrarily large systems.
Eitan Tadmor
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., Baranov, A. D., Kapustin, V. V.   +2 more
core  

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

Several unitarily invariant norm inequalities for matrices

Annals of Functional Analysis
This paper presents new inequalities involving unitarily invariant norms of matrices, extending classical results such as the Cauchy-Schwarz and arithmetic-geometric mean inequalities in the matrix setting. The authors build upon and generalize recent work by \textit{K. M. R. Audenaert} [Oper. Matrices 9, No.
Yang, Junjian, Ma, Shengyan
openaire   +2 more sources

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

On Geometry of p-Adic Coherent States and Mutually Unbiased Bases. [PDF]

Entropy (Basel), 2023
Zelenov E.
europepmc   +1 more source

Quantum adiabatic theorem for unbounded Hamiltonians with a cutoff and its application to superconducting circuits. [PDF]

Philos Trans A Math Phys Eng Sci, 2023
Mozgunov E, Lidar DA.
europepmc   +1 more source