Relative group completions
نویسنده
چکیده
We extend arbitrary group completions to the category of pairs (G, N) where G is a group and N is a normal subgroup of G. Relative localizations are defined as special cases. Our construction is a group-theoretical analogue of fibrewise completion and fibrewise localization in homotopy theory, and generalizes earlier work on relative localization of groups at primes. We use our approach to find conditions under which factoring out group radicals preserves exactness, and extend previous results about the effect of plus-constructions on homotopy fibre sequences.
منابع مشابه
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