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Interpolation operators on the space of holomorphic functions on the unit circle

Josef Kofroň (2001)

Applications of Mathematics

The aim of the paper is to get an estimation of the error of the general interpolation rule for functions which are real valued on the interval [ - a , a ] , a ( 0 , 1 ) , have a holomorphic extension on the unit circle and are quadratic integrable on the boundary of it. The obtained estimate does not depend on the derivatives of the function to be interpolated. The optimal interpolation formula with mutually different nodes is constructed and an error estimate as well as the rate of convergence are obtained. The general...

Lifting properties, Nehari theorem and Paley lacunary inequality.

Mischa Cotlar, Cora Sadosky (1986)

Revista Matemática Iberoamericana

A general notion of lifting properties for families of sesquilinear forms is formulated. These lifting properties, which appear as particular cases in many classical interpolation problems, are studied for the Toeplitz kernels in Z, and applied for refining and extending the Nehari theorem and the Paley lacunary inequality.

Measures connected with Bargmann's representation of the q-commutation relation for q > 1

Ilona Królak (1998)

Banach Center Publications

Classical Bargmann’s representation is given by operators acting on the space of holomorphic functions with scalar product z n , z k q = δ n , k [ n ] q ! = F ( z n z ¯ k ) . We consider the problem of representing the functional F as a measure. We prove the existence of such a measure for q > 1 and investigate some of its properties like uniqueness and radiality.

Morera type problems in Clifford analysis.

Emilio Marmolejo Olea (2001)

Revista Matemática Iberoamericana

The Pompeiu and the Morera problems have been studied in many contexts and generality. For example in different spaces, with different groups, locally, without an invariant measure, etc. The variations obtained exhibit the fascination of these problems.In this paper we present a new aspect: we study the case in which the functions have values over a Clifford Algebra. We show that in this context it is completely natural to consider the Morera problem and its variations. Specifically, we show the...

On a variational approach to truncated problems of moments

C.-G. Ambrozie (2013)

Mathematica Bohemica

We characterize the existence of the L 1 solutions of the truncated moments problem in several real variables on unbounded supports by the existence of the maximum of certain concave Lagrangian functions. A natural regularity assumption on the support is required.

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