Hyponormal operators with rank-two self-commutators
نویسندگان
چکیده
منابع مشابه
Hyponormal Operators with Rank-two Self-commutators
In this paper it is shown that if T ∈ L(H) satisfies (i) T is a pure hyponormal operator; (ii) [T ∗, T ] is of rank-two; and (iii) ker [T ∗, T ] is invariant for T , then T is either a subnormal operator or the Putinar’s matricial model of rank two. More precisely, if T |ker [T∗,T ] has the rank-one self-commutator then T is subnormal and if instead T |ker [T∗,T ] has the ranktwo self-commutato...
متن کاملOn Commutators of Isometries and Hyponormal Operators
A sufficient condition is obtained for two isometries to be unitarily equivalent. Also, a new class of M-hyponormal operator is constructed
متن کاملA Class of Subnormal Operators with Finite Rank Self-commutators
In this paper, the family of pure subnormal operators S with m.n.e. N and finite rank self-commutators satisfying c~(S) = closed unit disk and or(N) = unit circle U{a l , . . . , am} is studied. A necessary and sufficient condition for a pair of matrices {A, C} to be a complete unitary invariance of S in this family is given. The concrete model for some sub-family of this family is also given i...
متن کاملPolynomially hyponormal operators
A survey of the theory of k-hyponormal operators starts with the construction of a polynomially hyponormal operator which is not subnormal. This is achieved via a natural dictionary between positive functionals on specific convex cones of polynomials and linear bounded operators acting on a Hilbert space, with a distinguished cyclic vector. The class of unilateral weighted shifts provides an op...
متن کاملON p-HYPONORMAL OPERATORS
In this paper we show that p-hyponormal operators with 0 / ∈ σ(|T | 1 2 r ) are subscalar. As a corollary, we get that such operators with rich spectra have non-trivial invariant subspaces.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Mathematical Analysis and Applications
سال: 2009
ISSN: 0022-247X
DOI: 10.1016/j.jmaa.2008.09.062