Weighted operator least squares problems and the J ‐trace in Krein spaces
نویسندگان
چکیده
منابع مشابه
Operator convexity in Krein spaces
We introduce the notion of Krein-operator convexity in the setting of Krein spaces. We present an indefinite version of the Jensen operator inequality on Krein spaces by showing that if (H , J) is a Krein space, U is an open set which is symmetric with respect to the real axis such that U ∩ R consists of a segment of real axis and f is a Kreinoperator convex function on U with f(0) = 0, then f(...
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ژورنال
عنوان ژورنال: Mathematische Nachrichten
سال: 2020
ISSN: 0025-584X,1522-2616
DOI: 10.1002/mana.201900066