3 papers
math.CT2025
Realization of relational presheaves
Yorgo Chamoun, Samuel Mimram
Relational presheaves generalize traditional presheaves by going to the category of sets and relations (as opposed to sets and functions) and by allowing functors which are lax. Th…
math.CT2025
De Morgan's law in toposes I
Olivia Caramello, Yorgo Chamoun
We study toposes satisfying De Morgan's law, in particular we give characterizations of geometric theories whose classifying topos is De Morgan, clarifying the link with the amalga…
math.AT2025
Non-Hausdorff manifolds over locally ordered spaces via sheaf theory
Yorgo Chamoun, Emmanuel Haucourt
Locally ordered spaces can be used as topological models of concurrent programs: the local order models the irreversibility of time during execution. Under certain conditions, one…