1 citations · 1 across the 3 of their papers we have counts for
11 papers
Toposes over which essential implies locally connected
Jens Hemelaer
We introduce the notion of an EILC topos: a topos such that every essential geometric morphism with codomain is locally connected. We then show that the…
Geometric morphisms between toposes of monoid actions: factorization systems
Jens Hemelaer, Morgan Rogers
Let M, N be monoids, and PSh(M), PSh(N) their respective categories of right actions on sets. In this paper, we systematically investigate correspondences between properties of geo…
Solution to a problem by FitzGerald
Jens Hemelaer, Morgan Rogers
FitzGerald identified four conditions (RI), (UR), (RI*) and (UR*) that are necessarily satisfied by an algebra, if its monoid of endomorphisms has commuting idempotents. We show th…
An essential, hyperconnected, local geometric morphism that is not locally connected
Jens Hemelaer, Morgan Rogers
We give an example of an essential, hyperconnected, local geometric morphism that is not locally connected, arising from our work-in-progress on geometric morphisms $\mathbf{PSh}(M…
Monoid Properties as Invariants of Toposes of Monoid Actions
Jens Hemelaer, Morgan Rogers
We systematically investigate, for a monoid , how topos-theoretic properties of , including the properties of being atomic, strongly compact, local, totally con…
Duality for noncommutative frames
Karin Cvetko-Vah, Jens Hemelaer, Lieven Le Bruyn
We characterize the left-handed noncommutative frames that arise from sheaves on topological spaces. Further, we show that a general left-handed noncommutative frame arises fro…