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.AT2026

Norms in equivariant homotopy theory

Tobias Lenz, Sil Linskens, Phil Pützstück

We show that the -category of normed algebras in genuine -spectra, as introduced by Bachmann-Hoyois, is modelled by strictly commutative algebras in -symmetric spectr…

math.CT2025

Revisiting -naturality of the Yoneda embedding

Tobias Lenz

We show that the Yoneda embedding 'is' -natural with respect to the functoriality of presheaves via left Kan extension, refining the -categorical result pro…

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

Mackey functors and classical equivariant -theory

Tobias Lenz

We show that the spectral Mackey functors associated to the equivariant algebraic -theory spectra of Guillou-May and Merling (originally constructed using pointset models) can b…

math.AT2025

Global homotopy theory via spectral Mackey functors

Tobias Lenz

We show that Hausmann's model of global stable homotopy theory in terms of symmetric spectra is equivalent to the -category of spectral Mackey functors in the sense of Barw…