Journal of Inequalities and Applications 
Volume 2006 (2006), Article ID 76489, 9 pages
doi:10.1155/JIA/2006/76489

Orthogonality preserving property, Wigner equation, and stability

Jacek Chmieliński

 Instytut Matematyki, Akademia Pedagogiczna w Krakowie, Podchorążych 2, Kraków 30-084, Poland
Received 3 November 2005; Accepted 2 July 2006

Abstract

We deal with the stability of the orthogonality preserving property in the class of mappings phase-equivalent to linear or conjugate-linear ones. We give a characterization of approximately orthogonality preserving mappings in this class and we show some connections between the considered stability and the stability of the Wigner equation.