An extremal problem for functions annihilated by a Toeplitz operator
نویسندگان
چکیده
منابع مشابه
An Extremal Problem for Characteristic Functions
Suppose E is a subset of the unit circle T and H∞ ⊂ L∞ is the Hardy subalgebra. We examine the problem of finding the distance from the characteristic function of E to znH∞. This admits an alternate description as a dual extremal problem. Precise solutions are given in several important cases. The techniques used involve the theory of Toeplitz and Hankel operators as well as the construction of...
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ژورنال
عنوان ژورنال: Analysis and Mathematical Physics
سال: 2019
ISSN: 1664-2368,1664-235X
DOI: 10.1007/s13324-019-00291-0