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is a group $G$, that admits finite $k(G, 1)$ and has no Baumslag-Solitar subgroups, necessarily hyperbolic?

This is the first question asked in Bestvina's article "Questions in Geometric Group Theory". Does anyone know if there has been any progress made on this problem? Is the question answered if $G$ is ...
scott spencer's user avatar
5 votes
0 answers
140 views

Reference request: Name or use of this group of diffeomorphisms of the disc

Let $k \in \{0,\infty\}$, $G\subseteq \operatorname{Diff}^k(D^n)$ be the set of diffeomorphisms $\phi:D^n\to D^n$ of the closed $n$-disc $D^n$ (with its boundary) satisfying the following: $ \phi(S_r^...
ABIM's user avatar
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4 votes
0 answers
79 views

On the induction step in Theorem 2.6 of "Homological stability for linear groups" by Kallen

I am currently reading the proof of the connectivity theorem of Wilberd van der Kallen (Theorem 2.6 in https://link.springer.com/article/10.1007/BF01390018) for a seminar talk. I am a little stuck on ...
Womm's user avatar
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4 votes
0 answers
453 views

Problem 1.8 from Kirby's list

Context I looked through a book called "Problems in Low-Dimensional Topology", where Rob Kirby lists a set of problems. He provides a list of problems, states their conjectures, and ...
saver_of_light's user avatar
3 votes
0 answers
93 views

References for variations of Seifert–van Kampen's theorem: HNN extensions and "sensible" intersections

A basic consequence of the Seifert–van Kampen theorem is the following. Theorem: Consider a union of topological spaces $X$, $Y$ whose intersection $X\cap Y = Z$ is open connected and $\pi_1$-...
NWMT's user avatar
  • 1,033
3 votes
0 answers
115 views

Finite homology of a homogeneous space

Let $\Gamma$ be a cocompact lattice in $\operatorname{SL}(2,\mathbb R)$ and $X=\operatorname{SL}(2,\mathbb R)/\Gamma$ be the underlying homogeneous space. Can the homology group $H_1(X,\mathbb Z)$ be ...
William of Baskerville's user avatar
3 votes
0 answers
393 views

What about a Cayley n-complex for n>2?

Let $G$ be a finitely presented group. The Cayley graph of the finite generating set is a $1$-complex where the $0$-cells are the elements of $G$ and the $1$-cells are given by the generators (...
Sebastien Palcoux's user avatar
3 votes
0 answers
128 views

Salvetti complexes and cohomology of affine completion of Artin groups $E_6$ and $E_7$

After the solution of the Brieskorn-Arnold Pham conjecture on the asphericity of a space for affine Artin groups by Paolini and Salvetti MR4243019 (arXiv), I would like to know if there are ...
Nicolas Boerger's user avatar
3 votes
0 answers
127 views

Methods for constructing or checking for nontrivial classes in de Rham cohomology with local coefficients

Let $M$ be a smooth manifold (possibly with boundary), $E \to M$ a flat vector bundle, and $\mathcal{L}$ the corresponding sheaf of parallel sections. Given a de Rham cohomology class $[\omega] \in H^...
ಠ_ಠ's user avatar
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2 votes
0 answers
185 views

Can the 2-complex associated to a finitely presented group be triangulated?

Let G be a finitely presented group. K is the 2-complex associated to G which is constructed as taught in Algebraic Topology. That is , 1-cells corresponding to generators and 2-cells corresponding to ...
BiM's user avatar
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1 vote
0 answers
113 views

Question on models for $EG$ for a $G$-CW complex

I am having trouble finding information on a definition in P. Hanham's PhD thesis paper. recall that given a discrete group $G$ a $G$-CW-complex $X$ is a CW-complex equipped with a topological $G$ ...
Dominic Petti's user avatar
1 vote
0 answers
278 views

Homology of spherical braid groups

By the spherical braid group, I mean the fundamental group of the configuration space of distinct unordered points in $S^2$. I am wondering what is known about the group homology of the spherical ...
2jp9nq0's user avatar
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