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arXiv · 2312.06390

$\mathcal{MID}$ and safe quotients for GRWS

Chafiq Benhida·Raúl E. Curto·George R. Exner
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Abstract

Geometrically regular weighted shifts (in short, GRWS) are those with weights $\alpha (N,D)$ given by $\alpha_n (N,D) = \sqrt{\frac{p^n + N}{p^n + D}}$, where $p > 1$ and $(N,D)$ is fixed in the open unit square $ (-1, 1)\times (-1, 1)$. We study here the zone of pairs $ (M,P)$ for which the weight $\frac{\alpha (N,D) }{ \alpha (M,P) }$ gives rise to a moment infinitely divisible ($ \mathcal {MID}$) or a subnormal weighted shift, and deduce immediately the analogous results for product weights $\alpha (N,D) \alpha (M,P)$, instead of quotients. Useful tools introduced for this study are a pair of partial orders on the GRWS.

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BibTeXRIS

Chafiq Benhida, Raúl E. Curto, George R. Exner. 2023-12-11. $\mathcal{MID}$ and safe quotients for GRWS. https://doi.org/10.1016/j.jmaa.2024.128443

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