On the Moore-Penrose inverse in rings with involution
Dijana Mosić · Miskolc mathematical notes/Mathematical notes · 2017
We study equivalent conditions to those given in Penrose equations for an element to be the Moore-Penrose inverse of a given element in a ring with involution, using the concept of EP, normal, bi-EP, bi-normal, l-(or r-)quasi-EP, l-(or r-)quasi-normal and *-cancellable elements.The mentioned conditions are weaker that the one of being self-adjoint.