Acta mathematica scientia, Series B >
ISOMORPHISMS AND DERIVATIONS IN C*-ALGEBRAS
Received date: 2008-08-31
Online published: 2011-01-20
In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality:
||f(x) + f(y) + 2f(z) + 2f(w)|| ≤||2f (x + y/2+ z + w) (0.1)
This is applied to investigate isomorphisms between C*-algebras, Lie C*-algebras and JC*-algebras, and derivations on C*-algebras, Lie C*algebras and JC*-algebras, associated with the Cauchy-Jensen functional equation
2f (x + y/2+ z + w )= f(x) + f(y) + 2f(z) + 2f(w). (0.2)
Lee Jung-Rye , Shin Dong-Yun . ISOMORPHISMS AND DERIVATIONS IN C*-ALGEBRAS[J]. Acta mathematica scientia, Series B, 2011 , 31(1) : 309 -320 . DOI: 10.1016/S0252-9602(11)60231-2
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