User Paul Fabel

14 votes

Accepted

Existence of a non-null-homotopic simple closed curve

answered Oct 12, 2015 at 20:00

12 votes

Accepted

Existence of a continuous section

answered Nov 22, 2015 at 2:23

11 votes

Are the higher homotopy groups of the Hawaiian earring trivial?

answered Apr 20, 2014 at 11:39

11 votes

A space in which sequences have unique limits but compact sets need not be closed

answered Sep 7, 2012 at 8:25

10 votes

Accepted

Is the homeomorphism class of a connected open set of C determined by its fundamental group?

answered May 31, 2013 at 20:44

10 votes

Accepted

"All retracts are closed" as separation axiom

answered Dec 18, 2014 at 11:53

10 votes

Is any function taking compact sets to compact sets, and connected sets to connected sets, necessarily continuous?

answered Nov 16, 2015 at 21:11

10 votes

Why the "W" in CGWH (compactly generated weakly Hausdorff spaces)?

answered Dec 11, 2015 at 4:45

8 votes

A space in which sequences have unique limits but compact sets need not be closed

answered Sep 7, 2012 at 9:00

5 votes

What are your favorite concrete examples of limits or colimits that you would compute during lunch?

answered Jan 18, 2014 at 3:56

5 votes

US does not imply AB

answered Feb 18, 2014 at 12:52

5 votes

Inserting an open and simply-connected set between a compact set and an open set

answered Feb 11, 2015 at 14:34

4 votes

When is the boundary of an open planar set a Jordan curve?

answered Jul 28, 2015 at 2:52

3 votes

Fundamental Examples

answered Oct 24, 2015 at 2:18

3 votes

Homotopy problem for infinite dimensional topological space II

answered Aug 21, 2013 at 11:11

2 votes

Largest Hausdorff quotient

answered Nov 18, 2013 at 4:39

2 votes

Accepted

Sufficient conditions for Hausdorffness

answered Aug 8, 2011 at 23:26

2 votes

Connected, maximal compact, but not $T_2$

answered Apr 17, 2015 at 8:30

2 votes

Is a certain subset of the disc a convex set?

answered Dec 8, 2015 at 5:39

2 votes

Is “factoring through a dendrite loop” preserved under deletion?

answered Apr 4, 2018 at 21:00

1 vote

Bound on the period of the identity (in a free group) for an automorphism followed by left-multiplication

answered Jan 7, 2022 at 21:39

1 vote

Is every T0 2nd countable space the quotient of a separable metric space?

answered Jan 21, 2014 at 18:17

0 votes

What are some natural examples of "bimorphism" classes?

answered Apr 27, 2016 at 17:24

Stack Exchange Network

23 Answers

Existence of a non-null-homotopic simple closed curve

Existence of a continuous section

Are the higher homotopy groups of the Hawaiian earring trivial?

A space in which sequences have unique limits but compact sets need not be closed

Is the homeomorphism class of a connected open set of C determined by its fundamental group?

"All retracts are closed" as separation axiom

Is any function taking compact sets to compact sets, and connected sets to connected sets, necessarily continuous?

Why the "W" in CGWH (compactly generated weakly Hausdorff spaces)?

A space in which sequences have unique limits but compact sets need not be closed

What are your favorite concrete examples of limits or colimits that you would compute during lunch?

US does not imply AB

Inserting an open and simply-connected set between a compact set and an open set

When is the boundary of an open planar set a Jordan curve?

Fundamental Examples

Homotopy problem for infinite dimensional topological space II

Largest Hausdorff quotient

Sufficient conditions for Hausdorffness

Connected, maximal compact, but not $T_2$

Is a certain subset of the disc a convex set?

Is “factoring through a dendrite loop” preserved under deletion?

Bound on the period of the identity (in a free group) for an automorphism followed by left-multiplication

Is every T0 2nd countable space the quotient of a separable metric space?

What are some natural examples of "bimorphism" classes?