Multiplicative Cauchy functional equation in the cone of positive-definite symmetric matrices

Konstancja Bobecka, Jacek Wesołowski
2003 Annales Polonici Mathematici  
We solve the multiplicative Cauchy equation for real functions of symmetric positive definite matrices under the differentiability restriction. The specialty of the problem lies in the symmetry of the multiplication. 2000 Mathematics Subject Classification: 39B52, 15A15, 39B22.
doi:10.4064/ap82-1-1 fatcat:ssctpptlpjd7fdl6cwurfv4na4