Persymmetric Jacobi matrices with square-integer eigenvalues and dispersionless mass-spring chains

Almost All Integer Matrices Have No Integer Eigenvalues

In a recent issue of this MONTHLY, Hetzel, Liew, and Morrison [4] pose a rather natural question: what is the probability that a random n× n integer matrix is diagonalizable over the field of rational numbers? Since there is no uniform probability distribution on Z, we need to exercise some care in interpreting this question. Specifically, for an integer k ≥ 1, let Ik = {−k,−k + 1, . . . , k − ...

On the location of the eigenvalues of Jacobi matrices

Using some well known concepts on orthogonal polynomials, some recent results on the location of eigenvalues of tridiagonal matrices of very large order are extended. A significant number of important papers are unified. c © 2006 Elsevier Ltd. All rights reserved.

Two modified Jacobi methods for M-matrices

Jacobi matrices

We discuss the relationships among Jacobi matrices, orthogonal polynomials, spectral measure, moments, minors, Gaussian quadrature, resolvents and continued fractions in the simplest setting, namely the finite-dimensional one. The formal structure is essentially the same as that in the infinite-dimensional setting, where it leads into the rich analytic world of orthogonal polynomials on the rea...

Eigenvalues and Pseudo-eigenvalues of Toeplitz Matrices

The eigenvalues of a nonhermitian Toeplitz matrix A are usually highly sensitive to perturbations, having condition numbers that increase exponentially with the dimension N. An equivalent statement is that the resolvent ( ZZ A)’ of a Toeplitz matrix may be much larger in norm than the eigenvalues alone would suggest-exponentially large as a function of N, even when z is far from the spectrum. B...