Research output: Contribution to journal › Article › peer-review
The Detectable Subspace for the Friedrichs Model. / Brown, B. M.; Marletta, M.; Naboko, S.; Wood, I. G.
In: Integral Equations and Operator Theory, Vol. 91, No. 5, 49, 01.10.2019.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - The Detectable Subspace for the Friedrichs Model
AU - Brown, B. M.
AU - Marletta, M.
AU - Naboko, S.
AU - Wood, I. G.
PY - 2019/10/1
Y1 - 2019/10/1
N2 - This paper discusses how much information on a Friedrichs model operator can be detected from ‘measurements on the boundary’. We use the framework of boundary triples to introduce the generalised Titchmarsh–Weyl M-function and the detectable subspaces which are associated with the part of the operator which is ‘accessible from boundary measurements’. The Friedrichs model, a finite rank perturbation of the operator of multiplication by the independent variable, is a toy model that is used frequently in the study of perturbation problems. We view the Friedrichs model as a key example for the development of the theory of detectable subspaces, because it is sufficiently simple to allow a precise description of the structure of the detectable subspace in many cases, while still exhibiting a variety of behaviours. The results also demonstrate an interesting interplay between modern complex analysis, such as the theory of Hankel operators, and operator theory.
AB - This paper discusses how much information on a Friedrichs model operator can be detected from ‘measurements on the boundary’. We use the framework of boundary triples to introduce the generalised Titchmarsh–Weyl M-function and the detectable subspaces which are associated with the part of the operator which is ‘accessible from boundary measurements’. The Friedrichs model, a finite rank perturbation of the operator of multiplication by the independent variable, is a toy model that is used frequently in the study of perturbation problems. We view the Friedrichs model as a key example for the development of the theory of detectable subspaces, because it is sufficiently simple to allow a precise description of the structure of the detectable subspace in many cases, while still exhibiting a variety of behaviours. The results also demonstrate an interesting interplay between modern complex analysis, such as the theory of Hankel operators, and operator theory.
KW - Detectable subspace
KW - Friedrichs model
KW - Inverse problem
KW - M-function
KW - GENERALIZED RESOLVENTS
KW - OPERATOR
KW - INVERSE PROBLEMS
UR - http://www.scopus.com/inward/record.url?scp=85073510738&partnerID=8YFLogxK
U2 - 10.1007/s00020-019-2548-9
DO - 10.1007/s00020-019-2548-9
M3 - Article
AN - SCOPUS:85073510738
VL - 91
JO - Integral Equations and Operator Theory
JF - Integral Equations and Operator Theory
SN - 0378-620X
IS - 5
M1 - 49
ER -
ID: 49775481