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arXiv · 1408.3252

Homotopy excision and cellularity

Wojciech Chacholski·Jerome Scherer·Kay Werndli
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Abstract

Consider a push-out diagram of spaces C <-- A --> B, construct the homotopy push-out, and then the homotopy pull-back of the diagram one gets by forgetting the initial object A. We compare the difference between A and this homotopy pull-back. This difference is measured in terms of the homotopy fibers of the original maps. Restricting our attention to the connectivity of these maps, we recover the classical Blakers-Massey Theorem.

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Wojciech Chacholski, Jerome Scherer, Kay Werndli. 2014-08-14. Homotopy excision and cellularity. https://arxiv.org/abs/1408.3252

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