Approximation numbers of composition operators on the Hardy space of the ball and of the polydisk
نویسندگان
چکیده
We give general estimates for the approximation numbers of composition operators on the Hardy space on the ball Bd and the polydisk D . Mathematics Subject Classification 2010. Primary: 47B33 – Secondary: 32A07 – 32A35 – 32A70 – 46E22 – 47B07 Key-words. approximation numbers; bounded symmetric domain; composition operator; Hardy space; polydisk; Reinhardt domain; several complex variables
منابع مشابه
Bilateral composition operators on vector-valued Hardy spaces
Let $T$ be a bounded operator on the Banach space $X$ and $ph$ be an analytic self-map of the unit disk $Bbb{D}$. We investigate some operator theoretic properties of bilateral composition operator $C_{ph, T}: f ri T circ f circ ph$ on the vector-valued Hardy space $H^p(X)$ for $1 leq p leq +infty$. Compactness and weak compactness of $C_{ph, T}$ on $H^p(X)$ are characterized an...
متن کاملSpectrum and essential spectrum of linear combinations of composition operators on the Hardy space H2
Let -----. For an analytic self-map --- of --- , Let --- be the composition operator with composite map --- so that ----. Let --- be a bounded analytic function on --- . The weighted composition operator --- is defined by --- . Suppose that --- is the Hardy space, consisting of all analytic functions defined on --- , whose Maclaurin cofficients are square summable. .....
متن کاملSOME REMARKS ON WEAKLY INVERTIBLE FUNCTIONS IN THE UNIT BALL AND POLYDISK
We will present an approach to deal with a problem of existence of (not) weakly invertible functions in various spaces of analytic functions in the unit ball and polydisk based on estimates for integral operators acting between functional classes of different dimensions.
متن کاملWeighted Composition Operators from H∞ to the Bloch Space of a Bounded Homogeneous Domain
Let D be a bounded homogeneous domain in C. In this paper, we study the bounded and the compact weighted composition operators mapping the Hardy space H∞(D) into the Bloch space of D. We characterize the bounded weighted composition operators, provide operator norm estimates, and give sufficient conditions for compactness. We prove that these conditions are necessary in the case of the unit bal...
متن کاملCompact Hankel Operators on the Hardy Space of the Polydisk
We show that a big Hankel operator on the standard Hardy space of the polydisk D, n > 1, cannot be compact unless it is the zero operator. We also show that this result can be generalized to certain Hankel operators defined on Hardy-Sobolev spaces of the polydisk.
متن کامل