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ArticleOriginal scientific text

Title

Splitting obstructions and properties of objects in the Nil categories

Authors 1

Affiliations

  1. Institute of Mathematics, Warsaw University, Banacha 2, 02-097 Warszawa, Poland

Abstract

We show that the objects of Bass-Farrell categories which represent 0 in the corresponding Nil groups are precisely those which are stably triangular. This extends to Waldhausen's Nil group of the amalgamated free product with index 2 factors. Applications include a description of Cappell's special UNil group and reformulations of those splitting and fibering theorems which use the Nil groups.

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Fundamenta Mathematicae
1999/161/1-2
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Pages:
155-165
Main language of publication
English
Received
1997-12-30
Accepted
1999-02-09
Published
1999
Exact and natural sciences