We develop several iterative methods for computing generalized inverses using both first and second order optimization methods in C∗ -algebras. Known steepest descent iterative methods are generalized in C∗ -algebras. We introduce second order methods based on the minimization of the norms Ax − b 2 and x 2 by means of the known second order unconstrained minimization methods. We give several examples which illustrate our theory. 2000 Mathematics subject classification: primary 46H05, 47A05, 90C30, 15A09. Keywords and phrases: generalized inverses, Moore-Penrose inverse, iterative methods, nonlinear optimization.
Dragan S. Djordjevic