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Bounded projections in weighted function spaces in a generalized unit disc

A. H. Karapetyan (1995)

Annales Polonici Mathematici

Let M m , n be the space of all complex m × n matrices. The generalized unit disc in M m , n is >br>    R m , n = Z M m , n : I ( m ) - Z Z * i s p o s i t i v e d e f i n i t e . Here I ( m ) M m , m is the unit matrix. If 1 ≤ p < ∞ and α > -1, then L α p ( R m , n ) is defined to be the space L p R m , n ; [ d e t ( I ( m ) - Z Z * ) ] α d μ m , n ( Z ) , where μ m , n is the Lebesgue measure in M m , n , and H α p ( R m , n ) L α p ( R m , n ) is the subspace of holomorphic functions. In [8,9] M. M. Djrbashian and A. H. Karapetyan proved that, if R e β > ( α + 1 ) / p - 1 (for 1 < p < ∞) and Re β ≥ α (for p = 1), then     f ( ) = T m , n β ( f ) ( ) , R m , n , where T m , n β is the integral operator defined by (0.13)-(0.14). In the present paper, given 1 ≤ p <...

Bounded Toeplitz and Hankel products on weighted Bergman spaces of the unit ball

Małgorzata Michalska, Maria Nowak, Paweł Sobolewski (2010)

Annales Polonici Mathematici

We prove a sufficient condition for products of Toeplitz operators T f T , where f,g are square integrable holomorphic functions in the unit ball in ℂⁿ, to be bounded on the weighted Bergman space. This condition slightly improves the result obtained by K. Stroethoff and D. Zheng. The analogous condition for boundedness of products of Hankel operators H f H * g is also given.

B-regularity of certain domains in ℂⁿ

Nguyen Quang Dieu, Nguyen Thac Dung, Dau Hoang Hung (2005)

Annales Polonici Mathematici

We study the B-regularity of some classes of domains in ℂⁿ. The results include a complete characterization of B-regularity in the class of Reinhardt domains, we also give some sufficient conditions for Hartogs domains to be B-regular. The last result yields sufficient conditions for preservation of B-regularity under holomorphic mappings.

Caractérisations des zéros des fonctions de certaines classes de type Nevanlinna dans le bidisque

Philippe Charpentier (1984)

Annales de l'institut Fourier

Dans cet article, nous étudions les zéros des fonctions holomorphes dans le bidisque dont le logarithme du module vérifie une condition de croissance : nous caractérisons par une condition de type Blaschke les zéros des fonctions vérifiant D 2 δ D 2 ( z ) α log + | f ( z ) | d λ ( z ) &lt; , pour α &gt; - 1 , et nous donnons les conditions suffisantes pour des classes plus petites, en particulier pour la classe de Nevanlinna du bidisque.

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