A set with no Riesz basis of exponentials
نویسندگان
چکیده
We show that there exists a bounded subset of $\mathbb{R}$ such no system exponentials can be Riesz basis for the corresponding Hilbert space. An additional result gives lower bound constant any putative two dimensional disk.
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ژورنال
عنوان ژورنال: Revista Matematica Iberoamericana
سال: 2023
ISSN: ['2235-0616', '0213-2230']
DOI: https://doi.org/10.4171/rmi/1411