This book presents a wide panorama of methods to investigate the spectral properties of
block operator matrices. Particular emphasis is placed on classes of block operator matrices …

In most physical, chemical, biological and economic phenomena it is quite natural to
assume that the system not only depends on the present state but also on past occurrences …

The contraction semigroup S (t)= e^ t AS (t)= et A generated by the abstract linear dissipative
evolution equation ̈ u+ A u+ f (A) ̇ u= 0 u¨+ A u+ f (A) u˙= 0 is analyzed, where A is a …

Second order equations of the form ̈ z (t)+ A_0z (t)+ D ̇ z (t)= 0 are considered. Such
equations are often used as a model for transverse motions of thin beams in the presence of …

LOCATION OF THE SPECTRUM OF OPERATOR MATRICES WHICH ARE ASSOCIATED TO
SECOND ORDER EQUATIONS 1. Introduction The aim of this pap Page 1 O perators a nd M …

We discuss the unitary equivalence of generators GA, R associated with abstract damped
wave equations of the type ̈ u+ R ̇ u+ A^* A u= 0 in some Hilbert space H _1 and certain …

In general, better performance can be achieved with a controlled minimum-phase system
than a controlled nonminimum-phase system. We show that a wide class of second-order …

We establish a new method for obtaining nonconvex spectral enclosures for operators
associated with second‐order differential equations in a Hilbert space. In particular, we …

We discuss a Hilbert space method that allows to prove analytical well-posedness of a class
of linear strongly damped wave equations. The main technical tool is a perturbation lemma …

Damped wave equations with delay Page 1 Fields Institute Communications Volume 00,
0000 Damped wave equations with delay András Bátkai Mathematisches Institut Universität …