Stability of the index of a linear relation under compact perturbations
Volume 180 / 2007
                    
                    
                        Studia Mathematica 180 (2007), 95-102                    
                                        
                        MSC: Primary 47A53; Secondary 47A06.                    
                                        
                        DOI: 10.4064/sm180-1-7                    
                                    
                                                Abstract
We prove the stability under compact perturbations of the algebraic index of a Fredholm linear relation with closed range acting between normed spaces. Our main tool is a result concerning the stability of the index of a complex of Banach spaces under compact perturbations.
 
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            