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196
Answers
newest
activity
votes
33
What are your favorite instructional counterexamples?
Mar 2 '10 at 19:00
32
What are some of the big open problems in 3-manifold theory?
Aug 22 '10 at 22:07
29
Most interesting mathematics mistake?
Dec 15 '09 at 19:14
25
Mapping from a finite index subgroup onto the whole group
Mar 2 '12 at 13:19
25
finite generated group realized as fundamental group of manifolds
Feb 16 '10 at 3:12
24
Primes occurring as orders of elements of a finitely presented group
Feb 8 '13 at 13:03
21
Can a group be a universal Turing machine?
Feb 14 '12 at 10:01
21
〈x,y : x^p = y^p = (xy)^p = 1〉
Apr 24 '10 at 23:18
20
Fundamental groups of closed hyperbolic 3-manifolds are freely indecomposable
Mar 9 '11 at 4:33
17
Is there a finitely presented group with infinite homology over $\mathbb{Q}$?
Aug 7 '14 at 5:09
16
When is a extension of $\mathbb{Z}$ by a free group a CAT(0) group?
Feb 1 '11 at 15:46
16
How helpful is non-standard analysis?
Feb 25 '10 at 0:38
16
Fundamental group of 3-manifold with boundary
Nov 19 '09 at 18:04
15
What are the implications of the simple loop conjecture?
Nov 30 '15 at 21:27
15
A single paper everyone should read?
Nov 8 '09 at 5:18
15
Residual finiteness: why do we care?
Feb 28 '15 at 4:30
14
Is it decidable whether or not a collection of integer matrices generates a free group?
Sep 1 '11 at 6:00
13
Number of subgroups of a given index of a free group
Dec 2 '13 at 5:46
13
Walls of CAT(0) cube complex sufficiently far apart implies intersection of stabilizers finite
Dec 8 '12 at 18:11
13
Judging whether a finitely presented group is a 3-manifold group?
Oct 22 '12 at 9:38
13
Groups surjecting onto a free group
Nov 7 '11 at 10:17
13
When is a finitely generated group finitely presented?
Feb 10 '11 at 3:33
13
What can be said about a group from its presentation?
Aug 16 '10 at 14:46
12
A hyperbolic group with a small profinite completion
Jan 3 '15 at 21:53
12
Virtual fibering conjecture for cusped hyperbolic manifolds
Feb 12 '14 at 22:08
12
What finitely presented groups embed into GL_2?
Jul 23 '12 at 19:55
12
Applications of the notion of of Gromov-Hausdorff distance
Feb 27 '11 at 13:15
12
Applications of infinite graph theory
Sep 22 '10 at 21:28
12
does every right-angled coxeter group have a right-angled artin group as a subgroup of finite index?
Mar 18 '10 at 17:12
11
HNN extensions which are free products
Dec 9 '09 at 16:23
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