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27
What are some of the big open problems in 3-manifold theory?
23
What are your favorite instructional counterexamples?
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Primes occurring as orders of elements of a finitely presented group
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Mapping from a finite index subgroup onto the whole group
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〈x,y : x^p = y^p = (xy)^p = 1〉
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finite generated group realized as fundamental group of manifolds
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Fundamental groups of closed hyperbolic 3-manifolds are freely indecomposable
15
Can a group be a universal Turing machine?
15
A single paper everyone should read?
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Fundamental group of 3-manifold with boundary
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Most interesting mathematics mistake?
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How helpful is non-standard analysis?
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Groups surjecting onto a free group
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When is a extension of $\mathbb{Z}$ by a free group a CAT(0) group?
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Judging whether a finitely presented group is a 3-manifold group?
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does every right-angled coxeter group have a right-angled artin group as a subgroup of finite index?
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Classification problem for non-compact manifolds
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Finitely generated subgroups with infinite cyclic quotient
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Does every retraction of free groups arise from projection to a subset of a freely generating set?
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When is a finitely generated group finitely presented?
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residually finite groups with the same finite quotients
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Is it decidable whether or not a collection of integer matrices generates a free group?
10
When is an HNN extension a free group?
10
Is residual finiteness a profinite property?
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Recognizing the 4-sphere and the Adjan--Rabin theorem
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Finding hyperbolic metrics by approximation
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Applications of the notion of of Gromov-Hausdorff distance
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fundamental groups of surfaces
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Finitely generated subgroups of a product of free groups
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Examples of 3-manifolds with RFRS fundamental group
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