Thu, 12 Mar 2026
17:00
17:00
L3
Every join-semilattice with smallest element is isomorphic to the semilattice of compact open sets of some space
Marcus Tressl
(Manchester University)
Abstract
The assertion belongs to the representation theory of partially ordered sets,
to Non-Hausdorff topology and to domain theory, but is (co-)motivated by model
theoretic questions about the analysis of structures that can be seen as
global sections of a sheaf (like a ring or like a generalized product in the
Feferman-Vaught theorem). I will first explain my interest in the statement of
the title and then construct the asserted space in a functorial way.