activity
20242026
collaborators

11 papers

math.CT2026

Universality of span 2-categories and the construction of 6-functor formalisms

Bastiaan Cnossen, Tobias Lenz, Sil Linskens

Given an -category equipped with suitable wide subcategories , we show that the -category $\text{S}{\scriptstyle\text{PAN}}_2(C,E)_…

math.CT2026

A short proof of the universality of the relative Rezk nerve

Kensuke Arakawa, Bastiaan Cnossen

We give a concise, conceptual proof of the universality of the relative Rezk nerve, due to Mazel-Gee.

math.AT2025

Parametrized stability and the universal property of global spectra

Bastiaan Cnossen, Tobias Lenz, Sil Linskens

We develop a framework of parametrized semiadditivity and stability with respect to so-called atomic orbital subcategories of an indexing -category , extending work of N…

math.AT2025

Parametrized (higher) semiadditivity and the universality of spans

Bastiaan Cnossen, Tobias Lenz, Sil Linskens

Semiadditivity of an -category, i.e. the existence of biproducts, provides it with useful algebraic structure in the form of a canonical enrichment in commutative monoids.…

math.CT2025

Homotopical commutative rings and bispans

Bastiaan Cnossen, Rune Haugseng, Tobias Lenz +1

We prove that commutative semirings in a cartesian closed presentable -category, as defined by Groth, Gepner, and Nikolaus, are equivalent to product-preserving functors fr…

math.AT2025

Partial parametrized presentability and the universal property of equivariant spectra

Bastiaan Cnossen, Tobias Lenz, Sil Linskens

We introduce a notion of partial presentability in parametrized higher category theory and investigate its interaction with the concepts of parametrized semiadditivity and stabilit…