All Questions
Tagged with geometric-group-theory at.algebraic-topology
54 questions
8
votes
2
answers
596
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Infinite loop space maps into or out of BAut(F_n)
There is an inclusion $S_n \to Aut(F_n)$ from the symmetric group into the automorphism group of a free group. After applying the Quillen +-constriction, both $BS_{\infty}$ and $BF_{\infty}$ become ...
- 9,263
7
votes
2
answers
537
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Residually finite + torsion free + finite index = finite complex?
Suppose $G$ is a residually-finite group and $H < G$ a torsion-free subgroup of finite index.
What characterizes such $G$ such that $BH$ is homotopic to a finite complex?
I believe Serre showed ...
- 25k
18
votes
2
answers
790
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The kernel of the map from the handlebody group to Outer automorphisms of a free group
Let $K$ be a compact oriented 3-dimensional handlebody of genus $g$. The group $H_g$ of isotopy classes of diffeomorphisms of $K$ is called the handlebody group. (It embeds as a subgroup of the ...
- 28.2k
1
vote
1
answer
231
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blowing up the graphs
I heard the phrase from many mathematician using in the colloquials. I heard algebraic geometer using it. I was never bother about it until one of my professor responded to one my question as follows:
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- 121