Publikationen Prof. Trunk

Publikationen der Mitarbeiter

Publikationen am Fachgebiet

Results: 171
Created on: Sun, 28 Apr 2024 17:16:40 +0200 in 0.1235 sec


Henn, Mark-Alexander; Mehl, Christian; Trunk, Carsten
Hyponormal and strongly hyponormal matrices in inner product spaces. - In: Linear algebra and its applications, ISSN 0024-3795, Bd. 433 (2010), 6, S. 1055-1076

http://dx.doi.org/10.1016/j.laa.2010.04.050
Behrndt, Jussi; Luger, Annemarie; Trunk, Carsten;
On the negative squares of a class of self-adjoint extensions in Krein spaces. - Ilmenau : Techn. Univ., Inst. für Mathematik, 2010. - Online-Ressource (PDF-Datei: 34 S., 386 KB). - (Preprint ; M10,16)

A description of all exit space extensions with finitely many negative squares of a symmetric operator of defect one is given via Krein's formula. As one of the main results an exact characterization of the number of negative squares in terms of a fixed canonical extension and the behaviour of a function t (that determines the exit space extension in Krein's formula) at zero and at infinity is obtained. To this end the class of matrix valued D k n×n -functions is introduced and, in particular, the properties of the inverse of a certain D k 2×2 -function which is closely connected with the spectral properties of the exit space extensions with finitely many negative squares is investigated in detail. Among the main tools here are the analytic characterization of the degree of non-positivity of generalized poles of matrix valued generalized Nevanlinna functions and some extensions of recent factorization results.



http://www.db-thueringen.de/servlets/DocumentServlet?id=17238
Kuzhel, Sergii; Trunk, Carsten;
On a class of J-self-adjoint operators with empty resolvent set. - Ilmenau : Techn. Univ., Inst. für Mathematik, 2010. - Online-Ressource (PDF-Datei: 29 S., 257,3 KB). - (Preprint ; M10,11)
http://www.db-thueringen.de/servlets/DocumentServlet?id=16642
Philipp, Friedrich; Strauss, Vladimir A.; Trunk, Carsten;
Local spectral theory for normal operators in Krein spaces. - Ilmenau : Techn. Univ., Inst. für Mathematik, 2010. - Online-Ressource (PDF-Datei: 18 S., 172 KB). - (Preprint ; M10,09)

Sign type spectra are an important tool in the investigation of spectral properties of selfadjoint operators in Krein spaces. It is our aim to show that also sign type spectra for normal operators in Krein spaces provide insight in the spectral nature of the operator: If the real part and the imaginary part of a normal operator in a Krein space have real spectra only and if the growth of the resolvent of the imaginary part (close to the real axis) is of nite order, then the normal operator possesses a local spectral function dened for Borel subsets of the spectrum which belong to positive (negative) type spectrum. Moreover, the restriction of the normal operator to the spectral subspace corresponding to such a Borel subset is a normal operator in some Hilbert space. In particular, if the spectrum consists entirely out of positive and negative type spectrum, then the operator is similar to a normal operator in some Hilbert space.



http://www.db-thueringen.de/servlets/DocumentServlet?id=16640
Trunk, Carsten;
Spectral theory for second order systems and indefinite Sturm-Liouville problems. - Getr. Zählung Ilmenau : Techn. Univ., Habil.-Schr., 2010

Azizov, Tomas Ya.; Trunk, Carsten
On domains of PT symmetric operators related to -y"(x) + (-1) n x 2n y(x). - In: Journal of physics. Mathematical and theoretical. - Bristol : IOP Publ., 2007- , ISSN: 1751-8121 , ZDB-ID: 1363010-6, ISSN 1751-8121, Bd. 43.2010, 17, 175303, insges. 13 S.

http://dx.doi.org/10.1088/1751-8113/43/17/175303
Behrndt, Jussi;
Spectral analysis of singular ordinary differential operators with indefinite weights. - In: Journal of differential equations, ISSN 1090-2732, Bd. 248 (2010), 8, S. 2015-2037

http://dx.doi.org/10.1016/j.jde.2009.11.026
Trunk, Carsten;
Analyticity of semigroups related to a class of block operator matrices. - In: Operator algebras, operator theory and applications, (2010), S. 257-271

Behrndt, Jussi; Förster, Karl-Heinz; Trunk, Carsten
Recent advances in operator theory in Hilbert and Krein spaces : [7th Workshop on Operator Theory in Krein Spaces and Spectral Analysis, which was held at the Technische Universität Berlin, Germany, December 13 to 16, 2007]. - Basel : Birkhäuser, 2010. - XV, 307 S.. - (Operator theory ; 198) ISBN 978-3-0346-0179-5
Literaturangaben

Behrndt, Jussi; Katatbeh, Qutaibeh; Trunk, Carsten
Non-real eigenvalues of singular indefinite Sturm-Liouville operators. - In: Proceedings of the American Mathematical Society, ISSN 1088-6826, Bd. 137 (2009), 11, S. 3797-3806

https://doi.org/10.1090/S0002-9939-09-09964-X

Studienabschlussarbeiten

Anzahl der Treffer: 11
Erstellt: Sun, 28 Apr 2024 17:18:04 +0200 in 0.0158 sec