Square root problem and subnormal Aluthge transforms

نویسندگان

چکیده

For a non negative measure $\mu$ with $p$ atoms, we study the relation between Square Root Problem of and problem subnormality ${\tilde W_\mu}$ Aluthge transform associated unilateral weighted shift. We use an approach based on uniquely represented elements in support $\mu*\mu$. first show that if is subnormal, then $2p-1\le card(supp(\mu*\mu))\le [\frac{(p-1)^2+6}{2}]$. rewrite several results known for finitely atomic having at most five atoms give complete solution measures six atoms.

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ژورنال

عنوان ژورنال: Annals of Functional Analysis

سال: 2022

ISSN: ['2639-7390', '2008-8752']

DOI: https://doi.org/10.1007/s43034-022-00232-2