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I'm reading into classifying spaces for the moment and I have some questions about these things. I'm using the following definition:

Given a group $G$, a classifyingdefine the total space $EG$ for this group isto be a $G$-CW-complex that is contractible. Next we define $BG=EG/G$ to be the classifying space of $G$.

These spaces seem to exist and be unique up to $G$-homotopy for any group. I was wondering if there are criteria such that if these are satisfied by $G$, then the $G$-CWCW-complex $EG$$BG$ is finite (or, more general, of finite type)?

I do not immediatly find an obvious answer. For example to ask that $EG$$BG$ is finite already fails when taking $G$ to be finite. i.e. $\mathbb{Z}_2$ has $E\mathbb{Z}_2$$B\mathbb{Z}_2$ the infinite sphereprojective space $S^{\infty}$$\mathbb{R}P^{\infty}$, which has one cell in each dimension.

If someone could recommend additional literature on classifying spaces, please do. This will be highly appreciated!

I'm reading into classifying spaces for the moment and I have some questions about these things. I'm using the following definition:

Given a group $G$, a classifying space $EG$ for this group is a $G$-CW-complex that is contractible.

These spaces seem to exist and be unique up to $G$-homotopy for any group. I was wondering if there are criteria such that if these are satisfied by $G$, then the $G$-CW-complex $EG$ is finite (or, more general, of finite type)?

I do not immediatly find an obvious answer. For example to ask that $EG$ is finite already fails when taking $G$ to be finite. i.e. $\mathbb{Z}_2$ has $E\mathbb{Z}_2$ the infinite sphere $S^{\infty}$.

If someone could recommend additional literature on classifying spaces, please do. This will be highly appreciated!

Note: this question was edited after a comment below

I'm reading into classifying spaces for the moment and I have some questions about these things. I'm using the following definition:

Given a group $G$, define the total space $EG$ for this group to be a $G$-CW-complex that is contractible. Next we define $BG=EG/G$ to be the classifying space of $G$.

These spaces seem to exist and be unique up to $G$-homotopy for any group. I was wondering if there are criteria such that if these are satisfied by $G$, then the CW-complex $BG$ is finite (or, more general, of finite type)?

I do not immediatly find an obvious answer. For example to ask that $BG$ is finite already fails when taking $G$ to be finite. i.e. $\mathbb{Z}_2$ has $B\mathbb{Z}_2$ the infinite projective space $\mathbb{R}P^{\infty}$, which has one cell in each dimension.

If someone could recommend additional literature on classifying spaces, please do. This will be highly appreciated!

Source Link

Classifying spaces

I'm reading into classifying spaces for the moment and I have some questions about these things. I'm using the following definition:

Given a group $G$, a classifying space $EG$ for this group is a $G$-CW-complex that is contractible.

These spaces seem to exist and be unique up to $G$-homotopy for any group. I was wondering if there are criteria such that if these are satisfied by $G$, then the $G$-CW-complex $EG$ is finite (or, more general, of finite type)?

I do not immediatly find an obvious answer. For example to ask that $EG$ is finite already fails when taking $G$ to be finite. i.e. $\mathbb{Z}_2$ has $E\mathbb{Z}_2$ the infinite sphere $S^{\infty}$.

If someone could recommend additional literature on classifying spaces, please do. This will be highly appreciated!