
In this paper the study of cohomology theories, on a Hausdorff space X, introduced by the author in two previous papers [Contemp. Math. 12, 315- 329 (1982; Zbl 0518.55003); ''Cohomology theory on spaces'' (to appear)] is continued. If \(\Phi\) is a family of supports on X and H,\(\delta\) is a cohomology theory on X, then H,\(\delta\) has supports in \(\Phi\) if given \(u\in H(A)\) there exist B closed, \(C\in \Phi\) with \(A=B\cup C\) and \(u/B=0.\) If H,\(\delta\) and H',\(\delta\) ' are cohomology theories on the same space X, a homomorphism \(\phi\) from H,\(\delta\) to H',\(\delta\) ' is a natural transformation from H to H' commuting up to sign with \(\delta\) and \(\delta\) '. An ES theory [see the second op. cit. above] has supports in a family \(\Phi\) if the corresponding cohomology theory has supports in \(\Phi\). A cohomology theory H,\(\delta\) on a space X is said to be concentrated on a subset \(Y\subset X\) if \(H(A)=0\) for all closed \(A\subset X-Y\). An ES theory is said to be concentrated on Y if the corresponding cohomology theory is concentrated on Y. The paper is very dense, containing many major results. From these results we quote the following: a uniqueness theorem for two cohomology theories with the same family of supports, a characterization of cohomology with supports in suitable families in terms of limit properties, the construction of cohomology theories on a space X with supports in a given family \(\Phi\) from an ES theory on X, the relation between cohomology theories on X and on open subsets of X, a bijection between cohomology theories on X concentrated on an open set Y with supports in a suitable family \(\Phi\) /Y, a study of the particular cases of compact and paracompact supports, the proof of the fact that cohomology theories on a locally compact (locally paracompact) space X with compact (relatively paracompact) supports correspond to cohomology theories on the one-point compactification (paracompactification) \(X^+\) which are concentrated on X, a uniqueness theorem for additive cohomology theories with paracompact supports on finite dimensional normal spaces. All necessary notions, including those previously introduced by the author, are given in the paper.
55N20, 55N40, cohomology theories with the same family of supports, paracompact supports, cohomology theories on a Hausdorff space, natural transformation, additive cohomology theories, Axioms for homology theory and uniqueness theorems in algebraic topology
55N20, 55N40, cohomology theories with the same family of supports, paracompact supports, cohomology theories on a Hausdorff space, natural transformation, additive cohomology theories, Axioms for homology theory and uniqueness theorems in algebraic topology
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