Carathéodory-Julia type theorems for operator valued Schur functions
نویسندگان
چکیده
منابع مشابه
Carathéodory–Julia type theorems for operator valued Schur functions
We extend the Carathéodory–Julia theorem on angular derivatives as well as its higher order analogue established recently in [4] to the setting of contractive valued functions analytic on the unit disk. Carathéodory–Julia type conditions for an operator valued Schur-class function w are shown to be equivalent to the requirement that every function from the de Branges-Rovnyak space associated wi...
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ژورنال
عنوان ژورنال: Journal d'Analyse Mathématique
سال: 2008
ISSN: 0021-7670,1565-8538
DOI: 10.1007/s11854-008-0049-x