Webb1 maj 2024 · In the introduction to his paper "Flasque Model Structures for Presheaves" (in fact simplicial presheaves) Isaksen states on the top of page 2 that his model structure has a nice characterisation of fibrant objects and that "This is entirely unlike the injective model structures, where there is no explicit description of the fibrant objects". Webb8 dec. 2024 · simplicial homology generalized homology exact sequence, short exact sequence, long exact sequence, split exact sequence injective object, projective object …
Stacks and the Homotopy Theory of Simplicial Sheaves
Webb15 sep. 2010 · Matthias Wendt. In this paper, we discuss the construction of classifying spaces of fibre sequences in model categories of simplicial sheaves. One construction proceeds via Brown representability and provides a classification in the pointed model category. The second construction is given by the classifying space of the monoid of … Webb20 nov. 2024 · Let X be a locally fibrant simplicial sheaf on the big étale site for k, and let Y be a k scheme which is cohomologically proper. Then there is a Künneth-type isomorphism which is induced by an external cup-product pairing. Reductive algebraic groups G over k are cohomologically proper, by a result of Friedlander and Parshall. green peas rate
sheaf theory - Simplicial Sheaves? - MathOverflow
Webb15 aug. 2024 · A sheaf is a certain functor O p e n ( X) o p → C, where C is a 1-category, satisfying a certain limit condition. A stack is a functor O p e n ( X) o p → D, where D is a 2-category, satisfying a more complicated condition. In this case, D is the category of categories and C is the category of sets. – Mark Saving Aug 15, 2024 at 17:51 Webb22 feb. 2001 · The present paper defines stacks (from several points of view) as sheaves of groupoids satisfying an e#ective descent condition, and then discusses the basic homotopy theoretic properties of... WebbA simplicial sheaf (resp. simplicial presheaf) X is a simplicial object in the category of sheaves (resp. presheaves). In other words, Xis a con-travariant functor op!Shv(C), where … green peas production