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Approximate Isomorphisms in C *-Algebras

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Abstract

This paper is a survey on the Hyers–Ulam–Rassias stability of the following Cauchy–Jensen functional equation in C *-algebras:

$$2f\biggl(\frac{x+y}{2}+z\biggr)=f(x)+f(y)+2f(z).$$

The concept of Hyers–Ulam–Rassias stability originated from the Th.M. Rassias’ stability theorem (Rassias in Proc. Am. Math. Soc. 72:297–300, [1978]).

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Authors and Affiliations

  1. Department of Mathematics, Hanyang University, 133-791, Seoul, Republic of Korea

    Choonkil Park

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  1. Choonkil Park
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Correspondence to Choonkil Park.

Additional information

This work was supported by the research fund of Hanyang University (HY-2007-S).

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Park, C. Approximate Isomorphisms in C *-Algebras. Acta Appl Math 102, 71–85 (2008). https://doi.org/10.1007/s10440-008-9210-x

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