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Ken
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Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geometric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?


Edit: I should have been clear about what I meant by the "homotopy coherent nerve" of a topological category; what I meant was the composition

$$\mathsf{Cat}_{\mathsf{Top}}\xrightarrow{\operatorname{Sing}}\mathsf{Cat}_{\mathsf{sSet}}\xrightarrow{N}\mathsf{sSet},$$

where $\mathsf{Cat}_{\mathsf{Top}}$ and $\mathsf{Cat_{sSet}}$ are the category of small topologically/simplicially enriched categories, $\operatorname{Sing}$ is the base change along the singular complex functor, and $N$ is the homotopy coheret nerve functor.

Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geometric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?

Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geometric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?


Edit: I should have been clear about what I meant by the "homotopy coherent nerve" of a topological category; what I meant was the composition

$$\mathsf{Cat}_{\mathsf{Top}}\xrightarrow{\operatorname{Sing}}\mathsf{Cat}_{\mathsf{sSet}}\xrightarrow{N}\mathsf{sSet},$$

where $\mathsf{Cat}_{\mathsf{Top}}$ and $\mathsf{Cat_{sSet}}$ are the category of small topologically/simplicially enriched categories, $\operatorname{Sing}$ is the base change along the singular complex functor, and $N$ is the homotopy coheret nerve functor.

Fixed typo
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David White
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simplicial Simplicial nerve of a topological group

Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geomtricgeometric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?

simplicial nerve of a topological group

Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geomtric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?

Simplicial nerve of a topological group

Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geometric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?

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Ken
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simplicial nerve of a topological group

Given a group $G$, one way to construct the classifying (topological) space $BG$ is to regard $G$ as a category with one object and morphisms $G$, take its nerve, and then apply the geomtric realization functor.

Is an analogous statement true for topological groups? That is, given a topological group $G$, regarded as a topological category with one object, does the geometric realization of its homotopy coherent nerve model the classifying space $BG$?