Simplicial Set - Singular Set For A Space

Singular Set For A Space

The singular set of a topological space Y is the simplicial set defined by S(Y): n hom(|Δn|, Y) for each object n ∈ Δ, with the obvious functoriality condition on the morphisms. This definition is analogous to a standard idea in singular homology of "probing" a target topological space with standard topological n-simplices. Furthermore, the singular functor S is right adjoint to the geometric realization functor described above, i.e.:

homTop(|X|, Y) ≅ homS(X, SY)

for any simplicial set X and any topological space Y.

Read more about this topic:  Simplicial Set

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    Do I terrify?—

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    The within, all that inner space one never sees, the brain and the heart and other caverns where thought and feeling dance their sabbath.
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