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 WebbBetter: A simplicial ring A • is a sheaf on Δ (the category of finite ordered sets endowed with the chaotic topology). Then a simplicial module over A • is just a sheaf of modules. …
Cup Products in Sheaf Cohomology Canadian Mathematical …
Webbwhich is defined for any abelian sheaf A on the ´etale site for k. Here, L varies through the finite Galois extensions of k, and we write G = Gal(L/k) for the Galois group of such an extension L. Here, the scheme Sp(L) is the Zariski spectrum of the field L. The simplicial sheaf EG ×G Sp(L) is the Borel construction for the action of WebbNow X is a simplicial sheaf if for every object U 2Cand R 2 (U) the map ˝ R is an isomorphism (this definition is from [Jardine, 2007, p.37]). Note that an equivalent way to define simplicial sheaves would be as simplicial objects in the category of sheaves. The sim-plicial sheaves form a full subcategory SSh(C) of SPre(C) and there is solar wire for sale
model structure on simplicial presheaves in nLab
Webbsheaves are presheaves F satisfying a limit condition F(U) Ÿ= lim €• ž:V !U2R F(V) for all covering sieves R ı hom(U;) of C. A simplicial presheaf (respectively sheaf) is a simplicial object in the category of presheaves (respectively sheaves) on C; a simplicial presheaf is alternatively just a contravariant functor on C taking values in ... 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... WebbLet X be a finite simplicial complex. There is a well known linear algebra data description of (constructible with respect to the triangulation) sheaves of vector spaces on X. A … solarwise africa