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arXiv · 2304.14983

Homotopy truncations of homotopically stratified spaces

David Chataur·Martintxo Saralegi-Aranguren·Daniel Tanré
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Abstract

Intersection homology of Goresky and MacPherson can be defined from the Deligne sheaf, obtained from truncations of complexes of sheaves. As intersection homology is not the homology of a particular space, the search for a family of spaces whose homologies have properties analogous to intersection homology has developed. For some stratified spaces, M. Banagl has introduced such a family by using a topological truncation: the original link is replaced by a truncation of its homological Moore resolution. In this work, we study the dual approach in the Eckmann-Hilton sense : we consider the stratified space obtained by replacing the original link by a Postnikov approximation. The main result is that our construction restores the space constructed by Gajer to establish an intersection Dold-Thom theorem. We are conducting this study within the general framework of Quinn's homotopically stratified spaces.

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David Chataur, Martintxo Saralegi-Aranguren, Daniel Tanré. 2023-04-28. Homotopy truncations of homotopically stratified spaces. https://doi.org/10.1090/proc%2F16612

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