activity
20242026
collaborators

7 papers

math.CT2026

Definable functoriality of tensor-triangular spectra

Isaac Bird, Jordan Williamson

We prove that the homological and Balmer spectra in tensor-triangular geometry are functorial in certain definable functors, thereby providing an alternative perspective on functor…

math.RT2026

Definable functors and Brown--Adams representability

Isaac Bird

The question of when the derived category of a ring satisfies Brown--Adams representability is revisited via studying the transfer of pure homological dimension along definable fun…

math.CT2026

The shift-homological spectrum and parametrising kernels of rank functions

Isaac Bird, Jordan Williamson, Alexandra Zvonareva

For any compactly generated triangulated category we introduce two topological spaces, the shift-spectrum and the shift-homological spectrum. We use them to parametrise a family of…

math.RT2025

Purity, ascent, and periodicity for Gorenstein flat cotorsion modules

Isaac Bird

We investigate purity within the Frobenius category of Gorenstein flat cotorsion modules, which can be seen as an infinitely generated analogue of the Frobenius category of Gorenst…

math.CT2025

Definable functors between triangulated categories

Isaac Bird, Jordan Williamson

We systematically develop the theory of definable functors between compactly generated triangulated categories. Such functors preserve pure triangles, pure injective objects, and d…

math.CT2025

The homological spectrum via definable subcategories

Isaac Bird, Jordan Williamson

We develop an alternative approach to the homological spectrum of a tensor-triangulated category through the lens of definable subcategories. This culminates in a proof that the ho…