Strong Cohomological Dimension
Tom 56 / 2008
                    
                    
                        Bulletin Polish Acad. Sci. Math. 56 (2008), 183-189                    
                                        
                        MSC: 55M10, 54F45.                    
                                        
                        DOI: 10.4064/ba56-2-9                    
                                    
                                                Streszczenie
We characterize strong cohomological dimension of separable metric spaces in terms of extension of mappings. Using this characterization, we discuss the relation between strong cohomological dimension and (ordinal) cohomological dimension and give examples to clarify their gaps. We also show that $\mathop{\rm Ind}_G X = \dim_G X$ if $X$ is a separable metric ANR and $G$ is a countable Abelian group. Hence $\dim_{\mathbb{Z}} X = \dim X$ for any separable metric ANR $X$.
 
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            