Approximation theorem for evolution operators
Volume 154 / 2003
                    
                    
                        Studia Mathematica 154 (2003), 195-206                    
                                        
                        MSC: Primary 47D06.                    
                                        
                        DOI: 10.4064/sm154-3-1                    
                                    
                                                Abstract
This paper is devoted to the study of the approximation problem for the abstract hyperbolic differential equation $u'(t)=A(t)u(t)$ for $t\in [0,T],$ where $\{ A(t):t\in [0,T]\}$ is a family of closed linear operators, without assuming the density of their domains.
 
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            