Let be the pushout of two groups , i = 1,2, over a common subgroup G, and H be the double mapping cylinder of the corresponding diagram of classifying spaces . Denote by ξ the diagram , where p is the natural map onto the unit interval. We show that the groups which occur in Waldhausen’s description of coincide with the continuously controlled groups , defined by Anderson and Munkholm. This also allows us to identify the continuously controlled groups which are known to form a homology theory in the variable ξ, with the “homology part” in Waldhausen’s description of . A similar result is also obtained for HNN extensions.
@article{bwmeta1.element.bwnjournal-article-fmv161i1p217bwm, author = {Hans Munkholm and Stratos Prassidis}, title = {Waldhausen's Nil groups and continuously controlled K-theory}, journal = {Fundamenta Mathematicae}, volume = {159}, year = {1999}, pages = {217-224}, zbl = {0938.19002}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-fmv161i1p217bwm} }
Munkholm, Hans; Prassidis, Stratos. Waldhausen’s Nil groups and continuously controlled K-theory. Fundamenta Mathematicae, Tome 159 (1999) pp. 217-224. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-fmv161i1p217bwm/
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