collaborators

5 papers

math.FA2024

A Toeplitz-like operator with rational matrix symbol having poles on the unit circle:\ Matrix representation and spectral analysis

G. J. Groenewald, S. ter Horst, J. Jaftha +1

In this paper we consider a class of unbounded Toeplitz operators with rational matrix symbols that have poles on the unit circle and employ state space realization techniques from…

math.FA2020

A Toeplitz-like operator with rational matrix symbol having poles on the unit circle: Fredholm properties

G. J. Groenewald, S. ter Horst, J. Jaftha +1

This paper concerns the analysis of an unbounded Toeplitz-like operator generated by a rational matrix function having poles on the unit circle T. It extends the analysis of such o…

math.FA2018

A Toeplitz-like operator with rational symbol having poles on the unit circle III: the adjoint

G. J. Groenewald, S. Ter Horst, J. Jaftha +1

This paper contains a further analysis of the Toeplitz-like operators on with rational symbol having poles on the unit circle that were previously studied in [5.6].…

math.FA2018

A Toeplitz-like operator with rational symbol having poles on the unit circle II: the spectrum

G. J. Groenewald, S. ter Horst, J. Jaftha +1

This paper is a continuation of our study of a class of Toeplitz-like operators with a rational symbol which has a pole on the unit circle. A description of the spectrum and its va…

math.FA2018

A Toeplitz-like operator with rational symbol having poles on the unit circle I: Fredholm properties

G. J. Groenewald, S. ter Horst, J. Jaftha +1

In this paper a definition is given for an unbounded Toeplitz-like operator with rational symbol which has poles on the unit circle. It is shown that the operator is Fredholm if an…