activity
19982023
most citedQuillen model structures for relative homological algebra

93 citations · 748 across the 47 of their papers we have counts for

collaborators

51 papers

math.HO2023★ 1 cited

The Beauty of Roots

John C. Baez

A "Littlewood polynomial" is a polynomial whose coefficients are all 1 or -1. The set of all complex roots of all Littlewood polynomials exhibits many complicated, beautiful and fa…

math.OA2023★ 3 cited

Isotropy fibers of ideals in groupoid C-algebras

Johannes Christensen, Sergey Neshveyev

Given a locally compact étale groupoid and an ideal in its groupoid C-algebra, we show that defines a family of ideals in group C-algebras of the isotropy groups an…

math.AT2023

Ext groups in Homotopy Type Theory

J. Daniel Christensen, Jarl G. Taxerås Flaten

Ext groups are fundamental homological invariants which have important applications in homotopy theory and algebra. In particular, they appear in the classical universal coefficien…

math.AT2023

Central H-spaces and banded types

Ulrik Buchholtz, J. Daniel Christensen, Jarl G. Taxerås Flaten +1

We introduce and study central types, which are generalizations of Eilenberg-Mac Lane spaces. A type is central when it is equivalent to the component of the identity among its own…

math.OA2022

Tracial weights on topological graph algebras

Johannes Christensen

We describe two kinds of regular invariant measures on the boundary path space of a second countable topological graph, which allows us to describe all extremal tracial weights on…

math.AT2021★ 1 cited

Non-accessible localizations

J. Daniel Christensen

In a 2005 paper, Casacuberta, Scevenels and Smith construct a homotopy idempotent functor on the category of simplicial sets with the property that whether it can be expressed…