HenrikRüping's user avatar
HenrikRüping's user avatar
HenrikRüping's user avatar
HenrikRüping
  • Member for 14 years, 1 month
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53 votes
4 answers
6k views

Are the rationals homeomorphic to any power of the rationals?

33 votes
1 answer
3k views

Collatz conjecture for numbers of th form $2^n +1$

32 votes
3 answers
4k views

Which spaces are inverse limits of discrete spaces ?

26 votes
7 answers
2k views

Tetrahedra with prescribed face angles

22 votes
5 answers
2k views

When is a extension of $\mathbb{Z}$ by a free group a CAT(0) group?

18 votes
3 answers
4k views

Is a inverse limit of compact spaces again compact ?

18 votes
2 answers
1k views

Are there space filling curves for the Hilbert cube?

17 votes
1 answer
693 views

Outer automorphisms of finite extensions

15 votes
4 answers
3k views

Automorphisms of $SL_n(\mathbb{Z})$

15 votes
2 answers
1k views

infinite dimensional CAT(0) groups

15 votes
0 answers
746 views

Are all these groups CAT(0) groups?

13 votes
4 answers
1k views

Can Lipschitz maps increase the Lebesgue dimension ?

13 votes
2 answers
363 views

Finding hyperbolic metrics by approximation

12 votes
1 answer
437 views

Does this group act geometrically on a Median space?

12 votes
2 answers
548 views

Self homeomorphisms of $S^2\times S^2$

12 votes
2 answers
940 views

Borromean braids

12 votes
4 answers
1k views

Topologizing free abelian groups

12 votes
3 answers
504 views

Small simplicial set models for BG

11 votes
1 answer
484 views

Is the norm element characteristic in modular group rings?

11 votes
4 answers
880 views

Are there unique geodesics in the NIL and SOL geometry?

11 votes
1 answer
525 views

Can dividing out a group action can increase the Lebesgue dimension ?

11 votes
1 answer
776 views

Are these abelian groups free?

9 votes
3 answers
1k views

Are subgroups of hyperbolic groups quasiisometrically embedded ?

9 votes
1 answer
340 views

On which space does $GL_n(F_p[X])$ act nicely?

8 votes
1 answer
887 views

geodesic 2-dimensional submanifolds of a Riemannian manifold [duplicate]

8 votes
1 answer
1k views

Is there an elementary way to show the triangular inequality for this expression ?

8 votes
5 answers
1k views

Analogues of the dihedral group

8 votes
1 answer
672 views

Is every solvable subgroup of $GL(n,\mathbb{Z})$ polycyclic?

8 votes
2 answers
469 views

Which groups have nice compactifications ?

8 votes
1 answer
221 views

local structure of free $\mathbb{R}$ actions