Zobrazeno 1 - 7
of 7
pro vyhledávání: '"Masoumeh Faghih-Ahmadi"'
Publikováno v:
Examples and Counterexamples, Vol 5, Iss , Pp 100131- (2024)
In this note it is shown that there is a bounded linear operator T on the Hardy Hilbert space H2 and a vector f in H2 such that the closure of the set {αTnf:α∈ℂ,n≥0} is not H2, but for every subsequence (nk)k=1∞ the closed linear span of {T
Externí odkaz:
https://doaj.org/article/6d32bbba8b994b858119e57777e8f343
Publikováno v:
Linear and Multilinear Algebra. 70:6989-6999
A bounded linear operator T on a complex Banach space X is superconvex-cyclic, if for some vector x in the space, C.co(orb(T,x)) is dense. Here, co(orb(T,x)) means the convex hull of {Tnx:n≥0}. In ...
Publikováno v:
Operators and Matrices. :381-387
Autor:
Masoumeh Faghih-Ahmadi
Publikováno v:
Bulletin of the Malaysian Mathematical Sciences Society. 39:901-911
We obtain some results on A-m-isometric operators. The paper consists of two parts. At first, we consider the products of A-m-isometries. It will be proved that the iterates of an A-m-isometry are all of this type. We discuss when an A-m-isometry bec
Publikováno v:
Volume: 40, Issue: 6 1211-1220
Turkish Journal of Mathematics
Turkish Journal of Mathematics
A bounded linear operator $T$ on a Hilbert space $\mathcal{H}$ is concave if, for each $x\in\mathcal{H}$, $\|T^2x\|^2-2\|Tx\|^2 +\|x\|^2 \leq 0$. In this paper, it is shown that if $T$ is a concave operator then so is every power of $T$. Moreover, we
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c7c7caecea220e215f5c13413945c679
https://dergipark.org.tr/tr/pub/tbtkmath/issue/35830/401536
https://dergipark.org.tr/tr/pub/tbtkmath/issue/35830/401536
Publikováno v:
Volume: 37, Issue: 3 483-489
Turkish Journal of Mathematics
Turkish Journal of Mathematics
We characterize the commutants of some multiplication operators on a Banach space of analytic functions defined on a bounded domain in the plane. Under certain conditions on the symbol of a multiplication operator, we show that its commutant is a set
Publikováno v:
Volume: 36, Issue: 4 596-600
Turkish Journal of Mathematics
Turkish Journal of Mathematics
Let Mz and B denote, respectively, the multiplication operator and the backward shift operator on a weighted Hardy space. We present sufficient conditions so that Mzn is similar to \bigoplus1nMz, and Bn is similar to \bigoplus1nB. The first part gene