Spectral theory of Toeplitz and Hankel operators on the Bergman space .
Taskinen, Jari, Virtanen, Jani A. (2008)
The New York Journal of Mathematics [electronic only]
Jan Swoboda, Harald K. Wimmer (2010)
Studia Mathematica
We study a class of operator polynomials in Hilbert space which are spectraloid in the sense that spectral radius and numerical radius coincide. The focus is on the spectrum in the boundary of the numerical range. As an application, the Eneström-Kakeya-Hurwitz theorem on zeros of real polynomials is generalized to Hilbert space.
Anne-Marie Charbonnel (1983)
Annales de la Faculté des sciences de Toulouse : Mathématiques
Damien Lamberton (1985)
Yuan, Jiangtao, Gao, Zongsheng (2007)
Journal of Inequalities and Applications [electronic only]
Vladimír Müller, Andrzej Sołtysiak (1989)
Studia Mathematica
Gil', Michael (2007)
ELA. The Electronic Journal of Linear Algebra [electronic only]
B. Aupetit, H. du T. Mouton (1994)
Studia Mathematica
Let A and B be two unitary Banach algebras. We study linear mappings from A into B which preserve the polynomially convex hull of the spectrum. In particular, we give conditions under which such surjective linear mappings are Jordan morphisms.
Volker Wrobel (1978)
Mathematische Annalen
Volker Wrobel (1989)
Mathematische Annalen
Ralph Chill, Yuri Tomilov (2007)
Banach Center Publications
Liu, Helong, Xu, Houbao, Yu, Jingyuan, Zhu, Guangtian (2005)
Journal of Applied Mathematics
Lassaad Aloui, Moez Khenissi (2007)
ESAIM: Control, Optimisation and Calculus of Variations
We prove uniform local energy estimates of solutions to the damped Schrödinger equation in exterior domains under the hypothesis of the Exterior Geometric Control. These estimates are derived from the resolvent properties.
Grzegorz Banaszak, Yoichi Uetake (2015)
Bulletin of the Polish Academy of Sciences. Mathematics
For an operator in a possibly infinite-dimensional Hilbert space of a certain class, we set down axioms of an abstract intersection theory, from which the Riemann hypothesis regarding the spectrum of that operator follows. In our previous paper (2011) we constructed a GNS (Gelfand-Naimark-Segal) model of abstract intersection theory. In this paper we propose another model, which we call a standard model of abstract intersection theory. We show that there is a standard model of abstract intersection...
Hansjörg Linden (1973)
Mathematische Zeitschrift
Konstantin Stathakopoulos (1985)
Δελτίο της Ελληνικής Μαθηματικής Εταιρίας
Konstantin Stathakopoulos (1980)
Δελτίο της Ελληνικής Μαθηματικής Εταιρίας
Alexander Fedotov, Frédéric Klopp (2005)
Annales scientifiques de l'École Normale Supérieure
Caixing Gu (2015)
Studia Mathematica
We study left n-invertible operators introduced in two recent papers. We show how to construct a left n-inverse as a sum of a left inverse and a nilpotent operator. We provide refinements for results on products and tensor products of left n-invertible operators by Duggal and Müller (2013). Our study leads to improvements and different and often more direct proofs of results of Duggal and Müller (2013) and Sid Ahmed (2012). We make a conjecture about tensor products of left n-invertible operators...
Duggal, B.P. (2005)
International Journal of Mathematics and Mathematical Sciences