Étale space of continuous functions

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Definition

Let and be topological spaces. The étale space of continuous functions at is a topological space along with an étale map down to , which arises from the sheaf of continuous functions from to . Some explicit aspects of this map:

  • The fiber of the map at any point , is the set of germs, at , of continuous functions from open neighbourhoods of to . In other words, it is the stalk at for the sheaf of continuous functions.
  • The topology on the étale space is given as follows: for every continuous function from an open subset of to , the set of germs of at points of is deemed to be an open subset. We now treat these open subsets as a subbasis for the topology of the étale space.