User Anton Petrunin

145 votes

15 answers

22k views

Is a free alternative to MathSciNet possible?

asked Feb 1, 2010 at 3:41

122 votes

37 answers

11k views

One-step problems in geometry

asked Dec 8, 2009 at 20:56

96 votes

79 answers

17k views

Elementary+Short+Useful

asked Apr 3, 2011 at 17:34

48 votes

2 answers

2k views

Can I wrap a suitcase with hair ties

asked Jun 7, 2022 at 21:29

42 votes

1 answer

3k views

Many flat totally geodesic surfaces ⇒ flat?

asked Jan 1, 2011 at 23:57

36 votes

0 answers

1k views

Two-convexity ⇒ Lefschetz?

asked Feb 17, 2011 at 22:12

36 votes

2 answers

2k views

Bodies of constant width?

asked Jan 26, 2012 at 17:57

35 votes

4 answers

3k views

Psychological test for Euclidean geometry [closed]

asked Dec 24, 2023 at 22:04

32 votes

2 answers

1k views

Term for "uncheckable constructions"

asked Nov 16, 2014 at 21:04

31 votes

3 answers

3k views

Optic fibers after Joseph O'Rourke

asked Oct 8, 2011 at 5:53

30 votes

6 answers

5k views

Euclid with Birkhoff

asked Jul 5, 2010 at 13:27

30 votes

3 answers

1k views

Diameter of m-fold cover

asked Dec 4, 2009 at 0:28

29 votes

1 answer

803 views

Running most of the time in a connected set

asked Aug 4, 2018 at 14:00

28 votes

5 answers

2k views

History of Mathematical Notation

asked Nov 28, 2015 at 12:20

27 votes

8 answers

5k views

Convex hull in CAT(0)

asked Nov 23, 2009 at 22:06

27 votes

6 answers

2k views

When shorter means smaller?

asked Nov 28, 2009 at 2:57

26 votes

1 answer

823 views

Disc bounded by a plane curve

asked Dec 16, 2016 at 19:59

25 votes

0 answers

1k views

Milnor's cartography problem

asked Nov 14, 2009 at 5:27

24 votes

4 answers

4k views

Fundamental group of 3-manifold with boundary

asked Nov 19, 2009 at 17:00

24 votes

1 answer

3k views

Universal group?

asked Mar 30, 2010 at 23:30

24 votes

3 answers

1k views

A problem on Gauss--Bonnet formula

asked Nov 12, 2018 at 21:12

23 votes

1 answer

1k views

Universal graph

asked Jan 22 at 17:16

23 votes

4 answers

2k views

Intrinsic metric with no geodesics

asked Feb 17, 2010 at 16:29

22 votes

4 answers

2k views

Minimal surface in a ball

asked Nov 3, 2009 at 17:27

22 votes

1 answer

646 views

Voronoi cell of lattices with the same profile

asked May 20, 2011 at 0:48

22 votes

0 answers

514 views

Sphere with bounded curvature

asked Jun 26, 2022 at 14:20

21 votes

1 answer

677 views

Diameter of a quotient of the infinite dimensional sphere

asked Sep 22, 2018 at 17:25

20 votes

6 answers

3k views

Perpetuum Mobile

asked Jan 6, 2010 at 3:41

20 votes

1 answer

2k views

А generalization of Gromov's theorem on polynomial growth

asked Jan 8, 2010 at 2:40

20 votes

2 answers

1k views

Rugged manifold

asked Oct 15, 2010 at 0:12

Stack Exchange Network

129 Questions

Is a free alternative to MathSciNet possible?

One-step problems in geometry

Elementary+Short+Useful

Can I wrap a suitcase with hair ties

Many flat totally geodesic surfaces ⇒ flat?

Two-convexity ⇒ Lefschetz?

Bodies of constant width?

Psychological test for Euclidean geometry [closed]

Term for "uncheckable constructions"

Optic fibers after Joseph O'Rourke

Euclid with Birkhoff

Diameter of m-fold cover

Running most of the time in a connected set

History of Mathematical Notation

Convex hull in CAT(0)

When shorter means smaller?

Disc bounded by a plane curve

Milnor's cartography problem

Fundamental group of 3-manifold with boundary

Universal group?

A problem on Gauss--Bonnet formula

Universal graph

Intrinsic metric with no geodesics

Minimal surface in a ball

Voronoi cell of lattices with the same profile

Sphere with bounded curvature

Diameter of a quotient of the infinite dimensional sphere

Perpetuum Mobile

А generalization of Gromov's theorem on polynomial growth

Rugged manifold