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Consensus is a well-studied problem in distributed sensing, computation and control, yet deriving useful and easily computable bounds on the rate of convergence to consensus remains a challenge. This paper discusses the use of seminorms for…

Systems and Control · Electrical Eng. & Systems 2025-08-29 Ron Ofir , Ji Liu , A. Stephen Morse , Brian D. O. Anderson

We prove a stability version of a general result that bounds the permanent of a matrix in terms of its operator norm. More specifically, suppose $A$ is an $n \times n$ matrix over $\mathbb{C}$ (resp. $\mathbb{R}$), and let $\mathcal{P}$…

Combinatorics · Mathematics 2016-06-27 Ross Berkowitz , Pat Devlin

We give some new criteria for a Hilbert space operator with spectrum on a smooth curve to be similar to a normal operator, in terms of pointwise and integral estimates of the resolvent. These results generalize criteria of Stampfli, Van…

Functional Analysis · Mathematics 2019-08-01 Michael A. Dritschel , Daniel Estévez , Dmitry Yakubovich

We consider real symmetric or complex hermitian random matrices with correlated entries. We prove local laws for the resolvent and universality of the local eigenvalue statistics in the bulk of the spectrum. The correlations have fast decay…

Probability · Mathematics 2018-03-01 Oskari Ajanki , Laszlo Erdos , Torben Krüger

Normal matrices, or matrices which commute with their adjoints, are of fundamental importance in pure and applied mathematics. In this paper, we study a natural functional on the space of square complex matrices whose global minimizers are…

Differential Geometry · Mathematics 2025-09-24 Tom Needham , Clayton Shonkwiler

This article aims at finding sufficient conditions for a family of meromorphic functions to be normal by involving partial sharing of sets with differential polynomials. Moreover, corresponding results for normal meromorphic functions are…

Complex Variables · Mathematics 2025-10-24 Kuldeep Singh Charak , Nikhil Bharti , Anil Singh

Every sufficiently big matrix with small spectral norm has a nearby low-rank matrix if the distance is measured in the maximum norm (Udell & Townsend, SIAM J Math Data Sci, 2019). We use the Hanson--Wright inequality to improve the estimate…

Numerical Analysis · Mathematics 2025-04-09 Stanislav Budzinskiy

We study sample covariance matrices arising from rectangular random matrices with i.i.d. columns. It was previously known that the resolvent of these matrices admits a deterministic equivalent when the spectral parameter stays bounded away…

Probability · Mathematics 2022-11-24 Clément Chouard

In this paper, we present several necessary and sufficient conditions for a logharmonic mapping to be normal i.e., we establish Marty's criterion, Zalcman-Pang lemma and the Lohwater-Pommerenke theorem for logharmonic mappings, along with…

Complex Variables · Mathematics 2025-05-26 Molla Basir Ahamed , Sanju Mandal

Given a real-valued positive semidefinite matrix, Williamson proved that it can be diagonalised using symplectic matrices. The corresponding diagonal values are known as the symplectic spectrum. This paper is concerned with the stability of…

Spectral Theory · Mathematics 2016-09-07 Martin Idel , Sebatian Soto Gaona , Michael M. Wolf

Let $V$ be a finite dimensional vector space over a field $\mathrm{k}$ of characteristic $0$. Let $A$ be a linear mapping of $V$ into itself. This paper gives a normal form for $A$, which gives a better description of the structure of $A$…

Symplectic Geometry · Mathematics 2014-05-28 Richard Cushman

We obtain sequences of inclusion sets for the spectrum, essential spectrum, and pseudospectrum of banded, in general non-normal, matrices of finite or infinite size. Each inclusion set is the union of the pseudospectra of certain…

Spectral Theory · Mathematics 2023-06-21 Simon N. Chandler-Wilde , Ratchanikorn Chonchaiya , Marko Lindner

We present a sufficient condition for irreducibility of forcing algebras and study the (non)-reducedness phenomenon. Furthermore, we prove a criterion for normality for forcing algebras over a polynomial base ring with coefficients in a…

Commutative Algebra · Mathematics 2017-07-28 Danny A. J. Gomez-Ramirez , Holger Brenner

In this paper we prove {\it a priori bounds} for infinitely renormalizable quadratic polynomials satisfying a ``molecule condition''. Roughly speaking, this condition ensures that the renormalization combinatorics stay away from the…

Dynamical Systems · Mathematics 2007-12-17 Jeremy Kahn , Mikhail Lyubich

For a square matrix $A$, the resolvent of $A$ at a point $z \in \mathbb{C}$ is defined as $(A-zI )^{-1}$. We consider the set of points $z \in \mathbb{C}$ where the relative difference in 2-norm between the resolvent and the nearest rank…

Numerical Analysis · Mathematics 2025-01-15 Anne Greenbaum , Faranges Kyanfar , Abbas Salemi

Consider a linear system of equations with interval coefficients, and each interval coefficient is associated with either a universal or an existential quantifier. The AE solution set and AE solvability of the system is defined by…

Numerical Analysis · Computer Science 2019-05-28 Milan Hladík

Here the definitions of nearest neighbor, robustness, concordance, and correlation, all of which feature in (Temple 2023) (henceforth abbreviated (T23)), are adjusted to make them completely mathematical while preserving their significance.…

Functional Analysis · Mathematics 2024-11-20 Bryan Cain

In this article we prove a sufficient condition of quasi-normality in higher dimension for a family of meromorphic mappings in which each pair of functions of family shares some moving hypersurfaces. We also prove a normality criterion…

Complex Variables · Mathematics 2019-09-04 Gopal Datt

We present a spectral analysis for matrix scaling and operator scaling. We prove that if the input matrix or operator has a spectral gap, then a natural gradient flow has linear convergence. This implies that a simple gradient descent…

Data Structures and Algorithms · Computer Science 2019-04-09 Tsz Chiu Kwok , Lap Chi Lau , Akshay Ramachandran

In this paper, we present a unified analysis of matrix completion under general low-dimensional structural constraints induced by {\em any} norm regularization. We consider two estimators for the general problem of structured matrix…

Machine Learning · Statistics 2018-11-26 Suriya Gunasekar , Arindam Banerjee , Joydeep Ghosh