Dice Question Streamline Icon: https://streamlinehq.com

Explicit exit-path category from fan combinatorics

Determine an explicit, combinatorial presentation of the exit-path category associated to the FLTZ stratification induced by a fan Σ, describing its objects and morphisms directly in terms of cones, faces, and their incidences, so that exodromy yields a functor-category model of constructible sheaves.

Information Square Streamline Icon: https://streamlinehq.com

Background

In zonotopal and unimodular cases, the FLTZ conic Lagrangian equals the conormal variety, and exodromy identifies constructible sheaves with functors on the exit-path category. Despite this, the authors do not have a direct combinatorial recipe that, given Σ, produces the exit-path category.

A concrete presentation of the exit-path category in terms of Σ would systematize exodromy-based descriptions of constructible sheaves and help connect toric combinatorics with categorical models across examples.

References

However, it is not clear to us how to write down the exit path category explicitly from the combinatorics of the fan.

Toric Mirror Symmetry for Homotopy Theorists (2501.06649 - Bai et al., 11 Jan 2025) in Epilogue, Remark after zonotopal/unimodular discussion