A Gleason–Kahane–Żelazko theorem for reproducing kernel Hilbert spaces
نویسندگان
چکیده
We establish the following Hilbert-space analogue of Gleason-Kahane-\.Zelazko theorem. If $\mathcal{H}$ is a reproducing kernel Hilbert space with normalized complete Pick kernel, and if $\Lambda$ linear functional on such that $\Lambda(1)=1$ $\Lambda(f)\ne0$ for all cyclic functions $f\in\mathcal{H}$, then multiplicative, in sense $\Lambda(fg)=\Lambda(f)\Lambda(g)$ $f,g\in\mathcal{H}$ $fg\in\mathcal{H}$. Moreover automatically continuous. give examples to show theorem fails hypothesis omitted. also discuss conditions under which has be point evaluation.
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ژورنال
عنوان ژورنال: Bulletin of The London Mathematical Society
سال: 2022
ISSN: ['1469-2120', '0024-6093']
DOI: https://doi.org/10.1112/blms.12618