Open AccessSome essential spectra of unbounded operator matrices pencils with non-diagonal domain and application
Author(s) -
Nedra Moalla,
Wafa Selmi
Publication year - 2022
Publication title -
filomat
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.449
H-Index - 34
eISSN - 2406-0933
pISSN - 0354-5180
DOI - 10.2298/fil2203763m
Subject(s) - mathematics , resolvent , diagonal , operator (biology) , diagonal matrix , domain (mathematical analysis) , pencil (optics) , pure mathematics , matrix (chemical analysis) , algebra over a field , mathematical analysis , geometry , biochemistry , chemistry , repressor , transcription factor , gene , mechanical engineering , materials science , engineering , composite material
In this paper, we investigate the stability of some essential spectra of a 2x2 block operator matrices pencil with unbounded entries and with non-diagonal domain (i.e a domain consisting of vectors which satisfy certain relations between their components) by using the resolvent of this kind of matrix operator in terms of the union of the essential spectra of the restriction of its diagonal operators entries. Furthermore, an example of two-group transport operators pencils is presented to illustrate the validity of the main results.