1 citations · 1 across the 5 of their papers we have counts for
7 papers · 1 filter
The smallest -pure subtopos and dimension theory
Jens Hemelaer
We introduce the notion of -pure geometric morphism between Grothendieck toposes, over a Grothendieck base topos . This is a higher-dimensional analogue of the conc…
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…
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…
A topological groupoid representing the topos of presheaves on a monoid
Jens Hemelaer
Butz and Moerdijk famously showed that every (Grothendieck) topos with enough points is equivalent to the category of sheaves on some topological groupoid. We give an alternative,…