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Related papers: Z-Pencils

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For a tuple $A=(A_1,\ A_2,\ ...,\ A_n)$ of elements in a unital algebra ${\mathcal B}$ over $\mathbb{C}$, its {\em projective spectrum} $P(A)$ or $p(A)$ is the collection of $z\in \mathbb{C}^n$, or respectively $z\in \mathbb{P}^{n-1}$ such…

Functional Analysis · Mathematics 2013-12-24 Patrick Cade , Rongwei Yang

We solve the problem of characterizing the Kronecker structure of a matrix pencil obtained by a rank-one perturbation of another matrix pencil. The results hold over arbitrary fields.

Combinatorics · Mathematics 2019-12-19 Itziar Baragaña , Alicia Roca

The main purpose of this article is to show that the numerical range of a linear pencil $\lambda A + B$ is equal to $\mathbb{C}$ if and only if $0$ belongs to the convex hull of the joint numerical range of $A$ and $B$. We also prove that…

Numerical Analysis · Mathematics 2022-11-04 Vadym Koval , Patryk Pagacz

We study pencils of plane cubics with only one base point and general member smooth, giving a complete classification. Under the additional hypothesis that all members are irreducible, we prove that there exists a unique non-isotrivial…

Algebraic Geometry · Mathematics 2025-08-04 Riccardo Moschetti , Gian Pietro Pirola , Lidia Stoppino

This paper is concerned with the reduction of the spectral problem for symmetric linear operator pencils to a spectral problem for the single operator. Also, a Rayleigh-Ritz-like bounds on eigenvalues of linear operator pencils are…

Spectral Theory · Mathematics 2015-10-05 Ivica Nakić

In this work, we consider symmetric positive definite pencils depending on two parameters. That is, we are concerned with the generalized eigenvalue problem $A(x)-\lambda B(x)$, where $A$ and $B$ are symmetric matrix valued functions in…

Numerical Analysis · Mathematics 2024-02-13 Luca Dieci , Alessandra Papini , Alessandro Pugliese

Let A,B denote binary forms of order d, and let C_{2r-1} = (A,B)_{2r-1} be the sequence of their linear combinants for r between 1 and (d+1)/2. It is known that C_1 and C_3 together determine the pencil generated by A and B, and hence…

Algebraic Geometry · Mathematics 2008-02-22 Abdelmalek Abdesselam , Jaydeep Chipalkatti

We survey index theorems counting eigenvalues of linearized Hamiltonian systems and characteristic values of polynomial operator pencils. We present a simple common graphical interpretation and generalization of the index theory using the…

Spectral Theory · Mathematics 2013-05-30 Richard Kollár , Radomír Bosák

The numerical solution of the generalized eigenvalue problem for a singular matrix pencil is challenging due to the discontinuity of its eigenvalues. Classically, such problems are addressed by first extracting the regular part through the…

Numerical Analysis · Mathematics 2024-07-17 Daniel Kressner , Bor Plestenjak

Complete eigenstructure, e.g., eigenvalues with multiplicities and minimal indices, of a skew-symmetric matrix pencil may change drastically if the matrix coefficients of the pencil are subjected to (even small) perturbations. These changes…

Representation Theory · Mathematics 2025-10-30 Sweta Das , Andrii Dmytryshyn

We analyze when an arbitrary matrix pencil is equivalent to a dissipative Hamiltonian pencil and show that this heavily restricts the spectral properties. In order to relax the spectral properties, we introduce matrix pencils with…

Numerical Analysis · Mathematics 2021-10-22 Christian Mehl , Volker Mehrmann , Michal Wojtylak

In this paper, spectral properties of matrices with (complex) zeon entries are investigated. It is shown that when $A$ is an $m\times m$ self-adjoint matrix whose characteristic polynomial $\chi_A(u)$ has $m$ ``spectrally simple'' zeros…

Rings and Algebras · Mathematics 2025-10-08 G. Stacey Staples

This paper is devoted to the study of perturbations of a matrix pencil, structured or unstructured, such that a perturbed pencil will reproduce a given deflating pair while maintaining the invariance of the complementary deflating pair. If…

Numerical Analysis · Mathematics 2020-03-09 Bibhas Adhikari , Biswa Nath Datta , Tinku Ganai , Michael Karow

Given bounded selfadjoint operators $A$ and $B$ acting on a Hilbert space $\mathcal{H}$, consider the linear pencil $P(\lambda)=A+\lambda B$, $\lambda\in\mathbb{R}$. The set of parameters $\lambda$ such that $P(\lambda)$ is a positive…

Functional Analysis · Mathematics 2022-01-10 Santiago Gonzalez Zerbo , Alejandra Maestripieri , Francisco Martínez Pería

We find the eigenvalues and eigenvectors of the n by n matrix with (i,j) entry \binom(i-1,n-j), establishing a conjecture of Peele and Stanica. Curiously, the eigenvectors can be chosen to form a matrix which is its own inverse.

Combinatorics · Mathematics 2007-05-23 David Callan

For each square matrix polynomial $P(\lambda)$ of odd degree, a block-symmetric block-tridiagonal pencil $\mathcal{T}_{P}(\lambda)$ was introduced by Antoniou and Vologiannidis in 2004, and a variation $\mathcal{R}_P(\lambda)$ was…

Numerical Analysis · Mathematics 2017-06-14 M. I. Bueno , F. M. Dopico , S. Furtado , L. Medina

Tubal scalars are usual vectors, and tubal matrices are matrices with every element being a tubal scalar. Such a matrix is often recognized as a third-order tensor. The product between tubal scalars, tubal vectors, and tubal matrices can be…

Spectral Theory · Mathematics 2021-07-28 Yuning Yang , Junwei Zhang

A generalized eigenvalue algorithm for tridiagonal matrix pencils is presented. The algorithm appears as the time evolution equation of a nonautonomous discrete integrable system associated with a polynomial sequence which has some…

Numerical Analysis · Mathematics 2016-01-19 Kazuki Maeda , Satoshi Tsujimoto

The QZ algorithm for computing eigenvalues and eigenvectors of a matrix pencil $A - \lambda B$ requires that the matrices first be reduced to Hessenberg-triangular (HT) form. The current method of choice for HT reduction relies entirely on…

Numerical Analysis · Mathematics 2018-05-31 Zvonimir Bujanović , Lars Karlsson , Daniel Kressner

We introduce a new class of structured matrix polynomials, namely, the class of M_A-structured matrix polynomials, to provide a common framework for many classes of structured matrix polynomials that are important in applications: the…

Numerical Analysis · Mathematics 2016-12-22 Froilán M. Dopico , Javier Pérez , Paul Van Dooren