Results 41 to 50 of about 3,753,549 (263)
Perturbation Results on Semi-Fredholm Operators and Applications
Journal of Inequalities and Applications, 2009 We give some results concerning stability in the Fredholm operators and Browder operators set, via the concept of measure of noncompactness. Moreover, we prove some localization results on the essential spectra of bounded operators on Banach space.
Boulbeba Abdelmoumen, Hamadi Baklouti
doaj +2 more sources
t-Entropy formulae for concrete classes of transfer operators
Журнал Белорусского государственного университета: Математика, информатика, 2019 t-Entropy is a principal object of the spectral theory of operators, generated by dynamical systems, namely, weighted shift operators and transfer operators.
Krzysztof Bardadyn +3 more
doaj +1 more source
The One-Third-Trick and Shift Operators [PDF]
, 2012 In this paper we obtain a representation as martingale transform operators for the rearrangement and shift operators introduced by T. Figiel. The martingale transforms and the underlying sigma algebras are obtained explicitly by combinatorial means.
R. Lechner
semanticscholar +1 more source
The structure of m-isometric weighted shift operators
, 2016 We obtain simple characterizations of unilateral and bilateral weighted shift operators that are m-isometric. We show that any such operator is a Hadamard product of 2-isometries and 3-isometries. We also study weighted shift operators whose powers are m-
Belal Abdullah, Trieu Le
semanticscholar +1 more source
Curvature and the Backward Shift Operators [PDF]
Proceedings of the American Mathematical Society, 1984 Let φ α {\varphi _\alpha } be a Möbius transformation of the unit disk D {\mathbf {D}} , | α | > 1 \left | \alpha \right | > 1 . We characterize all the operators T
openaire +2 more sources
Bounds on the spectral shift function and the density of states
, 2004 We study spectra of Schr\"odinger operators on $\RR^d$. First we consider a pair of operators which differ by a compactly supported potential, as well as the corresponding semigroups.
Hundertmark, Dirk +4 more
core +6 more sources
On t-entropy and variational principle for the spectral radii of transfer and weighted shift operators [PDF]
Ergodic Theory and Dynamical Systems, 2008 The paper deals with the variational principles for evaluation of the spectral radii of transfer and weighted shift operators associated with a dynamical system.
A. Antonevich, V. Bakhtin, A. Lebedev
semanticscholar +1 more source
A note on positive $\mathcal{AN}$ operators
, 2018 We show that positive absolutely norm attaining operators can be characterized by a simple property of their spectra. This result clarifies and simplifies a result of Ramesh. As an application we characterize weighted shift operators which are absolutely
Doust, Ian
core +1 more source
Disk-cyclicity and codisk-cyclicity of certain shift operators
, 2015 In this paper we characterize the disk-cyclicity and codisk-cyclicity of the bilateral weighted shifts on Hilbert space 2(Z,K ) with weight sequence {An}n∈Z of positive invertible diagonal operators on a separable complex Hilbert space K , respectively ...
Yu-Xia Liang, Ze‐hua Zhou
semanticscholar +1 more source
, 1996 The exactly solvable eigenproblems in Schr\"odinger quantum mechanics typically involve the differential "shift operators". In the standard supersymmetric (SUSY) case, the shift operator turns out to be of first order. In this work, I discuss a technique
C., David J. Fernandez
core +1 more source