56 citations · 236 across the 22 of their papers we have counts for
22 papers
Invertibility and parity in symmetric monoidal categories
Nick Gurski, Niles Johnson
We introduce a notion of parity for formal morphisms between invertible objects and use it to prove a corresponding coherence theorem. Parity is conceptually similar to the sign of…
Operads and equivariance
Alexander Corner, Nick Gurski
Operads were originally defined by May to have right actions of the symmetric groups, but later formulations have also used no groups actions at all or group actions by such famili…
Universal pseudomorphisms, with applications to diagrammatic coherence for braided and symmetric monoidal functors
Nick Gurski, Niles Johnson
This work introduces a general theory of universal pseudomorphisms and develops their connection to diagrammatic coherence. The main results give hypotheses under which pseudomorph…
The symmetric monoidal 2-category of permutative categories
Nick Gurski, Niles Johnson, Angélica M. Osorno
We define a tensor product for permutative categories and prove a number of key properties. We show that this product makes the 2-category of permutative categories closed symmetri…
2-categorical opfibrations, Quillen's Theorem B, and
Nick Gurski, Niles Johnson, Angélica M. Osorno
In this paper we show that the strict and lax pullbacks of a 2-categorical opfibration along an arbitrary 2-functor are homotopy equivalent. We give two applications. First, we sho…
The 2-dimensional stable homotopy hypothesis
Nick Gurski, Niles Johnson, Angélica M. Osorno
We prove that the homotopy theory of Picard 2-categories is equivalent to that of stable 2-types.