User Ryan Budney

83 votes

7 answers

7k views

Computational complexity of computing homotopy groups of spheres

asked Jul 8, 2010 at 7:37

61 votes

10 answers

10k views

Teaching proofs in the era of Google

asked Oct 9, 2010 at 3:39

60 votes

6 answers

7k views

Torsion in homology or fundamental group of subsets of Euclidean 3-space

asked Nov 7, 2009 at 1:14

59 votes

9 answers

7k views

Has anyone thought about creating a formal proof wiki with verifier?

asked Oct 5, 2010 at 22:06

32 votes

3 answers

2k views

A Pachner complex for triangulated manifolds

asked Aug 9, 2010 at 23:32

25 votes

3 answers

2k views

Persistent homology of Gaussian fields in Euclidean space

asked Dec 4, 2012 at 20:40

25 votes

2 answers

843 views

Which homotopy classes $S^3 \to S^2$ lift to embeddings $S^3 \to S^2 \times D^3$?

asked Jun 2, 2021 at 17:34

24 votes

2 answers

4k views

Isotopy extension theorems

asked Oct 23, 2013 at 15:01

24 votes

0 answers

1k views

Monoid structure of oriented manifolds with connect sum

asked Apr 8, 2012 at 18:32

24 votes

3 answers

2k views

How expensive is knowledge? Knots, Links, 3 and 4-manifold algorithms. [closed]

asked Aug 18, 2010 at 10:20

23 votes

4 answers

4k views

Curriculum reform success stories at an "average" research university

asked Dec 19, 2009 at 7:48

22 votes

1 answer

1k views

Word problem for fundamental group of submanifolds of the 4-sphere

asked Jul 21, 2010 at 11:17

22 votes

3 answers

1k views

"Largest" finite-dimensional Lie subgroups of Diff(S^n), are they known?

asked Jun 13, 2010 at 18:55

19 votes

9 answers

4k views

Hironaka desingularisation theorem -- new proofs in literature?

asked Nov 8, 2009 at 5:42

16 votes

5 answers

4k views

can you fool SnapPea?

asked Nov 10, 2009 at 20:39

16 votes

3 answers

1k views

Looking for "large knot" examples

asked Sep 4, 2013 at 20:07

15 votes

1 answer

540 views

Where is the Steenrod Realization problem at?

asked May 14 at 18:05

14 votes

0 answers

516 views

Structure of Gordian graph of knots

asked Nov 20, 2016 at 5:50

13 votes

1 answer

1k views

Mapping class groups of small Seifert-fibred 3-manifolds

asked Nov 16, 2013 at 22:08

13 votes

2 answers

1k views

Explicit embeddings of Cappell-Shaneson knots

asked Jul 23, 2011 at 0:01

12 votes

3 answers

1k views

Knot theory question: bridge number vs. min generators of fundamental group of complement

asked Jul 24, 2012 at 21:09

12 votes

1 answer

509 views

Lower bounds on dimensions of faithful representations of braid groups

asked Apr 3, 2012 at 8:26

12 votes

1 answer

535 views

4-manifolds in the 4-sphere such that it, and its complement have unsolvable word problem

asked Jul 27, 2010 at 8:59

12 votes

1 answer

678 views

Revisiting Gordon-Luecke theorem

asked Sep 14, 2021 at 20:48

12 votes

2 answers

561 views

Curvature flows for PL closed curves in the plane?

asked Sep 16, 2013 at 21:54

11 votes

2 answers

533 views

Simplicial replacements in smoothing theory

asked Oct 24, 2013 at 11:34

11 votes

2 answers

2k views

slice-ribbon for links (surely it's wrong)

asked Jan 14, 2010 at 1:13

11 votes

6 answers

1k views

Computing the structure of the group completion of an abelian monoid, how hard can it be?

asked Feb 3, 2010 at 7:24

11 votes

2 answers

619 views

Some mid-sized ¿hyperbolic? manifolds and SnapPea

asked Nov 14, 2012 at 23:47

11 votes

0 answers

511 views

The spheres operad

asked Sep 13, 2013 at 23:53

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56 Questions

Computational complexity of computing homotopy groups of spheres

Teaching proofs in the era of Google

Torsion in homology or fundamental group of subsets of Euclidean 3-space

Has anyone thought about creating a formal proof wiki with verifier?

A Pachner complex for triangulated manifolds

Persistent homology of Gaussian fields in Euclidean space

Which homotopy classes $S^3 \to S^2$ lift to embeddings $S^3 \to S^2 \times D^3$?

Isotopy extension theorems

Monoid structure of oriented manifolds with connect sum

How expensive is knowledge? Knots, Links, 3 and 4-manifold algorithms. [closed]

Curriculum reform success stories at an "average" research university

Word problem for fundamental group of submanifolds of the 4-sphere

"Largest" finite-dimensional Lie subgroups of Diff(S^n), are they known?

Hironaka desingularisation theorem -- new proofs in literature?

can you fool SnapPea?

Looking for "large knot" examples

Where is the Steenrod Realization problem at?

Structure of Gordian graph of knots

Mapping class groups of small Seifert-fibred 3-manifolds

Explicit embeddings of Cappell-Shaneson knots

Knot theory question: bridge number vs. min generators of fundamental group of complement

Lower bounds on dimensions of faithful representations of braid groups

4-manifolds in the 4-sphere such that it, and its complement have unsolvable word problem

Revisiting Gordon-Luecke theorem

Curvature flows for PL closed curves in the plane?

Simplicial replacements in smoothing theory

slice-ribbon for links (surely it's wrong)

Computing the structure of the group completion of an abelian monoid, how hard can it be?

Some mid-sized ¿hyperbolic? manifolds and SnapPea

The spheres operad