Abstract
In this paper, function spaces V∩l pA (w) are considered in the context of their multiplicative structure. The space V is determined by conditions on the values of a function in a disk (for example, CA,Lip Aα). We denote by l pA (w) the space of power series such that their Taylor coefficients are p-summable with weight w. For an analytic function Φ acting in a space of this type, we prove the following alternative: either Φ″(z)≡0, or the space is a Banach algebra with respect to pointwise multiplication. For a wide class of weights w, we establish the continuity of the identity embeddingmult(V∩l pA (w))↪multl pA . An estimate for the lp-multiplicative norm of random polynomials is found. This estimate can be considered as an extension of the known result by Salem-Zygmund. Bibliography: 10 titles.
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Additional information
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 232, 1996, pp. 50–72.
Translated by S. Shimorin.
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Vinogradov, S.A., Petrov, A.N. Inversion of a theorem on action of analytic functions and multiplicative properties of some subclasses of the hardy space H∞ . J Math Sci 92, 3573–3588 (1998). https://doi.org/10.1007/BF02440141
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DOI: https://doi.org/10.1007/BF02440141