Question

Is the collection of compact subsets of an open and convex set non-empty?

score 40 · Answer 1 · 2026-04-12 10:44:53

40

Views

Is the collection of compact subsets of an open and convex set non-empty?

Published on 12 Apr 2026 - 10:44

score 850 · Answer 2 · 2026-04-13 01:05:51

850

Views

Infimum of distance between two sets

Published on 13 Apr 2026 - 1:05

score 978 · Answer 3 · 2026-04-12 10:47:21

978

Views

Is there a countably compact sequential non-$T_2$ space that is not sequentially compact?

Published on 12 Apr 2026 - 10:47

score 1.1k · Answer 4 · 2026-04-11 20:34:21

1.1k

Views

Is the ball compact?

Published on 11 Apr 2026 - 20:34

score 108 · Answer 5 · 2026-04-14 06:49:48

108

Views

Lebesgue measure of a set

Published on 14 Apr 2026 - 6:49

score 280 · Answer 6 · 2026-04-11 00:43:14

280

Views

Compactness of $Y$ implies compactness of $X$

Published on 11 Apr 2026 - 0:43

score 2.3k · Answer 7 · 2026-04-14 23:59:22

2.3k

Views

Example of an open cover of $(0, 1)$ with no finite subcover

Published on 14 Apr 2026 - 23:59

score 456 · Answer 8 · 2026-04-18 08:15:40

456

Views

Prove that there doesn't exist a statement in first order logic which is valid iff G is a 3-sparse graph

Published on 18 Apr 2026 - 8:15

score 51 · Answer 9 · 2026-04-18 08:25:40

51

Views

a statement in the signature $\{c,f^1, R^2\}$ is satisfiable in a structure M $\iff $ for every element there exists a closed term t s.t. $t^M=a$

Published on 18 Apr 2026 - 8:25

score 65 · Answer 10 · 2026-04-15 09:41:04

65

Views

Proving non-compactness of a manifold

Published on 15 Apr 2026 - 9:41

score 841 · Answer 11 · 2016-02-23 02:35:15

841

Views

Points in the boundary of a compact set $K\subset\mathbb{R}^2$ reachable by a path in $K^c$

Published on 23 Feb 2016 - 2:35

score 560 · Answer 12 · 2016-02-24 00:04:25

560

Views

One-point compactification of a locally connected space.

Published on 24 Feb 2016 - 0:04

score 55 · Answer 13 · 2026-04-14 04:24:20

55

Views

Strangely defined ball compact in $L^p(I)$ or not?

Published on 14 Apr 2026 - 4:24

score 83 · Answer 14 · 2026-04-17 13:05:49

83

Views

The space of continuous fuctions is compact - Other direction!

Published on 17 Apr 2026 - 13:05

score 601 · Answer 15 · 2026-04-10 20:10:36

601

Views

Image of a precompact under the action of continuous function is a precompact

Published on 10 Apr 2026 - 20:10

List Question

Is the collection of compact subsets of an open and convex set non-empty?

Infimum of distance between two sets

Is there a countably compact sequential non-$T_2$ space that is not sequentially compact?

Is the ball compact?

Lebesgue measure of a set

Compactness of $Y$ implies compactness of $X$

Example of an open cover of $(0, 1)$ with no finite subcover

Prove that there doesn't exist a statement in first order logic which is valid iff G is a 3-sparse graph

a statement in the signature $\{c,f^1, R^2\}$ is satisfiable in a structure M $\iff $ for every element there exists a closed term t s.t. $t^M=a$

Proving non-compactness of a manifold

Points in the boundary of a compact set $K\subset\mathbb{R}^2$ reachable by a path in $K^c$

One-point compactification of a locally connected space.

Strangely defined ball compact in $L^p(I)$ or not?

The space of continuous fuctions is compact - Other direction!

Image of a precompact under the action of continuous function is a precompact

Trending Questions

Popular # Hahtags

Popular Questions