activity
20202025
most citedOn Diers theory of Spectrum I : Stable functors and right multi-adjoints

3 citations · 4 across the 9 of their papers we have counts for

collaborators

11 papers

math.CT2025

Morphisms and comorphisms of sites II -- Distributors of sites

Axel Osmond, Olivia Caramello

We introduce a notion of distributor of sites, involving suited analogs of flatness and cover-preservation, and show that this notion jointly generalizes those of morphism and como…

math.CT2025

Morphisms and comorphisms of sites I -- Double categories of sites

Olivia Caramello, Axel Osmond

We arrange morphisms and comorphisms of sites as the horizontal and vertical cells of a double category of sites; using the formalism of extensions and restrictions of presheaves,…

math.CT2025

On a (terminally connected, pro-etale) factorization of geometric morphisms

Olivia Caramello, Axel Osmond

We extend the classical (connected, etale) factorization of locally connected geometric morphisms into a (terminally connected, pro-etale) factorization for all geometric morphisms…

math.CT2022

Codescent and bicolimits of pseudo-algebras

Axel Osmond

We categorify cocompleteness results of monad theory, in the context of pseudomonads. We first prove a general result establishing that, in any 2-category, weighted bicolimits can…

math.CT2022

Bi-accessible and bipresentable 2-categories

Ivan Di Liberti, Axel Osmond

We develop a 2-dimensional version of accessibility and presentability compatible with the formalism of flat pseudofunctors. First we give prerequisites on the different notions of…

math.CT2021

Local right biadjoints, bistable pseudofunctors and 2-geometries for Grothendieck topoi

Axel Osmond

We provide bicategorical analogs of several aspects of the notion of geometry in the sense of the theory of spectrum. We first introduce a notion of local right biadjoint, and prov…

math.CT2021

On coslices and commas of locally finitely presentable categories

Axel Osmond

We give an explicit description of the generator of finitely presented objects of the coslice of a locally finitely presentable category under a given object, as consisting of all…

math.CT2021

The over-topos at a model

Olivia Caramello, Axel Osmond

With a model of a geometric theory in an arbitrary topos, we associate a site obtained by endowing a category of generalized elements of the model with a Grothendieck topology, whi…

math.CT2021

The spectral site revisited

Axel Osmond

We give the site-theoretic account of the spectral construction as first introduced by Coste. We provide a detailed examination of the geometric properties of the spectrum, in part…

math.CT2020★ 1 cited

On Diers theory of Spectrum II: Geometries and dualities

Axel Osmond

This second part comes to the construction of the spectrum associated to a situation of multi-adjunction. Exploiting a geometric understanding of its multi-versal property, the spe…

math.CT2020★ 3 cited

On Diers theory of Spectrum I : Stable functors and right multi-adjoints

Axel Osmond

Diers developed a general theory of right multi-adjoint functors leading to a purely categorical, point-set construction of spectra. Situations of multiversal properties return set…