On an upper bound for the number of characteristic values of an operator function

• Datum: 1998
• Hauptverfasser: Radzievskii, G. V., Радзиевский, Г. В.
• Format: Artikel
• Sprache: Russisch; Englisch
• Veröffentlicht: Institute of Mathematics, NAS of Ukraine 1998
• Online Zugang: https://umj.imath.kiev.ua/index.php/umj/article/view/4956
• Назва журналу: Ukrains’kyi Matematychnyi Zhurnal

We prove a theorem on an upper bound for the number of characteristic values of an operator-valued function that is holomorphic and bounded in a domain. This estimate is similar to the well-known inequality for zeros of a number function that is holomorphic and bounded in a domain. We derive several...