Stefan Friedl's user avatar
Stefan Friedl's user avatar
Stefan Friedl's user avatar
Stefan Friedl
  • Member for 13 years, 1 month
  • Last seen this week
  • University of Cologne
20 votes
1 answer
1k views

Topological embeddings of real projective space in euclidean space

19 votes
1 answer
441 views

Are the Morse inequalities sharp for 5-manifolds

19 votes
0 answers
305 views

are there high-dimensional knots with non-trivial normal bundle?

13 votes
1 answer
373 views

applications of Sard's to differential topology

13 votes
1 answer
1k views

Finite index subgroups of free groups and torsion-free amenable quotients of free groups

12 votes
1 answer
462 views

Is a generic closed orientable hyperbolic 3-manifold Haken?

11 votes
2 answers
508 views

The homeomorphism problem for hyperbolic 3-manifolds and the virtual Haken theorem

10 votes
1 answer
555 views

Piecewise linear Poincaré conjecture

8 votes
2 answers
234 views

PL-embeddings of balls into PL-manifolds

8 votes
5 answers
1k views

Does a group have a unique pro-p topology?

8 votes
3 answers
691 views

Finite simple groups with upper bound on order of elements

7 votes
6 answers
2k views

Elementary proof that an open subset of $\Bbb{R}^n$ does not have measure zero?

6 votes
1 answer
466 views

Rank gradients and HNN-extensions

6 votes
1 answer
821 views

subgroups of graph groups

3 votes
1 answer
508 views

Immersed Seifert surfaces of minimal genus