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 …

For a symmetric operator or relation A with infinite deficiency indices in a Hilbert space we
develop an abstract framework for the description of symmetric and self-adjoint extensions …

This is the first book to tackle the topological fixed point theory for block operator matrices
with nonlinear entries in Banach spaces and algebras. The authors present several …

In this paper, we investigate a detailed treatment of some subsets of essential spectra of a
closed multivalued linear operator. On the following, we will establish some results on …

Frobenius–Schur Factorization for Multivalued 2 χ 2 Matrices Linear Operator Page 1 Mediterr.
J. Math. (2017) 14:29 DOI 10.1007/s00009-016-0825-2 1660-5446/17/010001-29 published …

In this paper, we investigate the essential approximate point spectrum and the essential
defect spectrum of a 2× 2 block operator matrix on a Banach space. Furthermore, we apply …

Many coupled evolution equations can be described via 2× 2-block operator matrices of the
form A=[ABCD] in a product space X= X 1× X 2 with possibly unbounded entries. Here, the …

In this paper we study spectral properties of a 3× 3 block operator matrix with unbounded
entries and with domain consisting of vectors which satisfy certain relations between their …

In this paper, we investigate the Gustafson, Weidmann, Kato, Wolf, Schechter and Browder
essential spectra of a 2× 2 block matrix operator defined on a Banach space where entries …