Collection Topos à l'IHES
Organisateur(s)
Date(s)
13/05/2024
Pre-buildings as sheaves on the site of enclosures
Given an an apartment with action of the affine Weyl group, we can look at compact convex subsets whose boundaries are reflection hyperplanes. The category of these ``enclosures'' has a natural Grothendieck topology, whose sheaves constitute a natural environment in which to consider spaces which look like buildings or subsets thereof. This provides a technical tool, of a rather combinatorial nature, in our ongoing work with Katzarkov, Noll and Pandit on the construction of pre-buildings and versal harmonic maps.
