The Structure of Ext(a, Z) and Gch: Possible Co-moore Spaces
نویسنده
چکیده
We investigate what Ext(A, Z) can be when A is torsion-free and Hom(A, Z) = 0. We thereby give an answer to a question of Golasiński and Gonçalves which asks for the divisible Abelian groups which can be the type of a co-Moore space. 0. Introduction Marek Golasiński and Daciberg Lima Gonçalves have asked which divisible abelian groupsD can be the type of a co-Moore space [6, Problem 2.6]. In other words, for which D is there a topological space X such that for some n ≥ 2, the integral cohomology of X satisfies H(X,Z) =
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