A RetroSearch Logo

Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Search Query:

Showing content from https://en.wikipedia.org/wiki/Sheaf_of_spectra below:

Sheaf of spectra - Wikipedia

From Wikipedia, the free encyclopedia

In algebraic topology, a presheaf of spectra on a topological space X is a contravariant functor from the category of open subsets of X, where morphisms are inclusions, to the good category of commutative ring spectra. A theorem of Jardine says that such presheaves form a simplicial model category, where FG is a weak equivalence if the induced map of homotopy sheaves π ∗ F → π ∗ G {\displaystyle \pi _{*}F\to \pi _{*}G} is an isomorphism. A sheaf of spectra is then a fibrant/cofibrant object in that category.

The notion is used to define, for example, a derived scheme in algebraic geometry.


RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4