aequationes mathematicae

, Volume 54, Issue 1–2, pp 44–55 | Cite as

Jordan *-derivation pairs on a complex *-algebra

  • L. MolnárEmail author
Research Papers


The aim of this paper is to study the system of functional equations
$$\begin{gathered} E(x^3 ) = E(x)x*^2 + xF(x)x* + x^2 E(x) \hfill \\ F(x^3 ) = F(x)x*^2 + xE(x)x* + x^2 F(x) \hfill \\ \end{gathered} $$
, where Open image in new window is a complex *-algebra and Open image in new window are unknown additive functions. This problem arises naturally in connection with the question of representability of quadratic functionals via sesquilinear forms on modules over Open image in new window . We give a fairly complete solution of the problem and examine the case of some particular algebras.

AMS (1991) subject classification

Primary 16W10 39B52 Secondary 47B47 


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Copyright information

© Birkhäuser Verlag 1997

Authors and Affiliations

  1. 1.Institute of MathematicsLajos Kossuth UniversityDebrecen

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