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arXiv · 1812.05593

Canonical stratifications along bisheaves

Vidit Nanda·Amit Patel
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Abstract

A theory of bisheaves has been recently introduced to measure the homological stability of fibers of maps to manifolds. A bisheaf over a topological space is a triple consisting of a sheaf, a cosheaf, and compatible maps from the stalks of the sheaf to the stalks of the cosheaf. In this note we describe how, given a bisheaf constructible (i.e., locally constant) with respect to a triangulation of its underlying space, one can explicitly determine the coarsest stratification of that space for which the bisheaf remains constructible.

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Vidit Nanda, Amit Patel. 2020-07-10. Canonical stratifications along bisheaves. https://doi.org/10.1007/978-3-030-43408-3_15

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