We consider the quadratic eigenvalue problem (QEP) (λ2A+λB+ C)x = 0, where A,B, and C are Hermitian with A positive definite. The QEP is called hyperbolic if (x∗Bx)2 > 4(x∗Ax)(x∗Cx) for all nonzero x ∈ Cn. We show that a relatively efficient test for hyperbolicity can be obtained by computing the eigenvalues of the QEP. A hyperbolic QEP is overdamped if B is positive definite and C is positive ...

The numerical solution of singular eigenvalue problems is complicated by the fact that small perturbations coefficients may have an arbitrarily bad effect on accuracy. However, it has been known for a long time such are exceptional and standard solvers, as QZ algorithm, tend to yield good accuracy despite inevitable presence roundoff error. Recently, Lotz Noferini quantified this phenomenon int...

This paper presents a brief review of recent developments on quadratic inverse eigenvalue problem with applications to active vibration control and finite element model updating.

We consider the quadratic eigenvalue problem (QEP) (λ2M + λG + K)x = 0, where M = MT is positive definite, K = KT is negative definite, and G = −GT . The eigenvalues of the QEP occur in quadruplets (λ, λ,−λ,−λ) or in real or purely imaginary pairs (λ,−λ). We show that all eigenvalues of the QEP can be found efficiently and with the correct symmetry, by finding a proper solvent X of the matrix e...

Hyperbolic quadratic matrix polynomials Q(λ) = λ2A + λB + C are an important class of Hermitian matrix polynomials with real eigenvalues, among which the overdamped quadratics are those with nonpositive eigenvalues. Neither the definition of overdamped nor any of the standard characterizations provides an efficient way to test if a given Q has this property. We show that a quadratically converg...