Simplicial sheaf
Webb8 jan. 2016 · Jan 8, 2016 at 19:46 Like a sheaf takes values in Set, a simplicial sheaf takes values in simplicial sets. What your lecturer was talking about was a sheaf (set-valued) defined on a simplicial set, which amounts to regarding the simplicial set as a topological space (via it's geometric realization). In mathematics, more specifically in homotopy theory, a simplicial presheaf is a presheaf on a site (e.g., the category of topological spaces) taking values in simplicial sets (i.e., a contravariant functor from the site to the category of simplicial sets). Equivalently, a simplicial presheaf is a simplicial object in the … Visa mer Let F be a simplicial presheaf on a site. The homotopy sheaves $${\displaystyle \pi _{*}F}$$ of F is defined as follows. For any $${\displaystyle f:X\to Y}$$ in the site and a 0-simplex s in F(X), set Visa mer • Konrad Voelkel, Model structures on simplicial presheaves Visa mer The category of simplicial presheaves on a site admits many different model structures. Some of them are … Visa mer • cubical set • N-group (category theory) Visa mer • J.F. Jardine's homepage Visa mer
Simplicial sheaf
Did you know?
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 WebbSuitably formulated, we can associate to a simplicial sheaf Xa simplicial sheaf of monoids consisting of homotopy self-equivalences of X. To this monoid we can apply the bar construction. One can prove that the resulting space classifies fibre sequences of simplicial sheaves. In our approach to the construction of classifying spaces, we introduce
Webb1 jan. 1987 · More ex- plicitly, a cofibration (resp. topological weak equivalence) of simplicial sheaves is just a cofibration (resp. topological weak equivalence) in the simplicial presheaf category. A global fibration p: X ~ Y of simplicial sheaves is a map which has the right lifting property with respect to all trivial cofibrations of simplicial … 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.
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. … Webbrooted fibrations of simplicial sheaves. On the other hand, fibrations of simplicial sheaves correspond to principal bundles under homotopy self-equivalences. Suitably formulated, we can associate to a simplicial sheaf Xa simplicial sheaf of monoids consisting of homotopy self-equivalences of X. To this monoid we can apply the bar …
Webb19 juni 2024 · The local model structure on simplicial sheaves was proposed in Andre Joyal , Letter to Alexander Grothendieck , 11.4.1984, ( pdf scan ). This is, with BrownAHT …
WebbSimplicial schemes. A simplicial scheme is a simplicial object in the category of schemes, see Simplicial, Definition 14.3.1. Recall that a simplicial scheme looks like. Here there … polymer processing society 2023Webb28 mars 2024 · A local fibration or local weak equivalence of simplicial (pre)sheaves is defined to be one whose lifting property is satisfied after refining to some cover. … polymer processing society meeting 2023WebbFor any pointed simplicial sheaf X in ∆opSh(Sm/k) one defines the A1-homotopy group sheaves, πA1 i(X), to be the sheaves of simplicial homotopy groups of a fibrant replacement of X in the A1-model structure. Morel, in his foundational work in [5, Ch. 6] has defined, for every integer i, A1-homology groups HA1 i(X) and canonical Hurewicz … polymer processing properties pptWebbA 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 … shank locationWebb1 aug. 2015 · Stacks and the homotopy theory of simplicial sheaves. J. Jardine; Mathematics. 2001; Stacks are described as sheaves of groupoids G satisfying an eective descent condition, or equivalently such that the clas- sifying object BG satisÞes descent. The set of simplicial sheaf homotopy … Expand. 43. PDF. View 1 excerpt; Save. polymer processing societyWebb1 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". polymer processing and engineeringWebbA simplicial -module (sometimes called a simplicial sheaf of -modules) is a sheaf of modules over the sheaf of rings on associated to . We obtain a category of simplicial … shank london