On maps sending rank-κ idempotents to idempotents
نویسندگان
چکیده
منابع مشابه
On concentrating idempotents, a survey
A sum of exponentials of the form f(x) = exp (2 iN1x)+exp (2 iN2x)+ +exp (2 iNmx), where the Nk are distinct integers is called an idempotent trigonometric polynomial or, simply, an idempotent. It is known that for every p > 1; and every set S of the torus T = R=Z with jSj > 0; there are idempotents concentrated on S in the Lp sense. We sketch how this concentration phenomenon originated as a r...
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ژورنال
عنوان ژورنال: Operators and Matrices
سال: 2019
ISSN: 1846-3886
DOI: 10.7153/oam-2019-13-61