5 citations · 5 across the 3 of their papers we have counts for
6 papers
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…
On Supercompactly and Compactly Generated Toposes
Morgan Rogers
We present and characterize the classes of Grothendieck toposes having enough supercompact objects or enough compact objects. In the process, we examine the subcategories of superc…
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…
Toposes of Discrete Monoid Actions
Morgan Rogers
Properties of toposes of right -sets are studied, and these toposes are characterised up to equivalence by their canonical points. The solution to the corresponding Morita equiv…