Some examples in cohomological dimension theory
نویسندگان
چکیده
منابع مشابه
Some Examples in Cohomological Dimension Theory
It is well-known that dimX ≤ n if and only if every map of a closed subspace of X into the n-dimensional sphere Sn can be extended over X. It is also well-known that for the cohomological dimension dimGX of X with respect to an abelian coefficient group G, dimGX ≤ n if and only if every map of a closed subspace of X into the Eilenberg-Mac Lane complex K(G,n) extends over X. These properties giv...
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ژورنال
عنوان ژورنال: Pacific Journal of Mathematics
سال: 2002
ISSN: 0030-8730
DOI: 10.2140/pjm.2002.202.371