Question

What does a hyperreal version of the Cantor Set look like?

score 162 · Answer 1 · 2026-03-22 15:39:24

162

Views

What does a hyperreal version of the Cantor Set look like?

Published on 22 Mar 2026 - 15:39

score 213 · Answer 2 · 2018-09-06 12:47:54

213

Views

Sets definable by $\Sigma_2$ parameters

Published on 06 Sep 2018 - 12:47

score 167 · Answer 3 · 2018-09-06 17:06:59

167

Views

Simple ordinal question

Published on 06 Sep 2018 - 17:06

score 126 · Answer 4 · 2026-03-23 01:39:20

126

Views

How exactly does the oracle for a well-order of order type $\omega_1^\text{CK}$ operate?

Published on 23 Mar 2026 - 1:39

score 306 · Answer 5 · 2018-09-10 04:59:40

Is it possible to base the slow-growing hierarchy on the ordinal defined as “the height of the minimal model of ZFC (assuming it exists)”?

score 40 · Answer 6 · 2018-09-11 01:38:57

40

Views

Does $\{x \in \mathcal X:x>a \land x<b+1 \}$ give $(a,b+1)$ or $(a,b]$?

Published on 11 Sep 2018 - 1:38

score 148 · Answer 7 · 2018-09-15 15:07:58

148

Views

Proper initial segment $X$ of a von Neumann ordinal $Y$ has different order-isomorphism class from $Y$

Published on 15 Sep 2018 - 15:07

score 36 · Answer 8 · 2018-09-15 19:22:40

36

Views

A variant of the definition of an ordinal number

Published on 15 Sep 2018 - 19:22

score 324 · Answer 9 · 2026-03-22 14:49:58

324

Views

Applying transfinite recursion

Published on 22 Mar 2026 - 14:49

score 205 · Answer 10 · 2018-09-21 10:22:14

205

Views

Proving that if $\kappa$ is a limit ordinal, then $\alpha+\kappa=\bigcup_{\gamma\in\kappa}\left(\alpha+\gamma\right)$

Published on 21 Sep 2018 - 10:22

score 78 · Answer 11 · 2018-09-23 09:31:53

78

Views

Function with an ordinal domain: an ambiguity between a notation for a value and for an image

Published on 23 Sep 2018 - 9:31

score 205 · Answer 12 · 2018-09-24 09:15:09

205

Views

Why can the set of all natural numbers and omega be put in one-to-one correspondence with natural numbers?

Published on 24 Sep 2018 - 9:15

score 89 · Answer 13 · 2018-09-24 16:49:40

89

Views

A cofinal function into a limit ordinal

Published on 24 Sep 2018 - 16:49

score 51 · Answer 14 · 2018-09-26 16:50:42

51

Views

Understanding a proof about regular cardinals from "Set Theory for the Working Mathematician"

Published on 26 Sep 2018 - 16:50

score 202 · Answer 15 · 2026-03-25 13:56:28

202

Views

Does there exist a strict numeric measure of the strength for any set theory (relative to a corresponding proof-theoretic ordinal)?

Published on 25 Mar 2026 - 13:56

List Question

What does a hyperreal version of the Cantor Set look like?

Sets definable by $\Sigma_2$ parameters

Simple ordinal question

How exactly does the oracle for a well-order of order type $\omega_1^\text{CK}$ operate?

Is it possible to base the slow-growing hierarchy on the ordinal defined as “the height of the minimal model of ZFC (assuming it exists)”?

Does $\{x \in \mathcal X:x>a \land x<b+1 \}$ give $(a,b+1)$ or $(a,b]$?

Proper initial segment $X$ of a von Neumann ordinal $Y$ has different order-isomorphism class from $Y$

A variant of the definition of an ordinal number

Applying transfinite recursion

Proving that if $\kappa$ is a limit ordinal, then $\alpha+\kappa=\bigcup_{\gamma\in\kappa}\left(\alpha+\gamma\right)$

Function with an ordinal domain: an ambiguity between a notation for a value and for an image

Why can the set of all natural numbers and omega be put in one-to-one correspondence with natural numbers?

A cofinal function into a limit ordinal

Understanding a proof about regular cardinals from "Set Theory for the Working Mathematician"

Does there exist a strict numeric measure of the strength for any set theory (relative to a corresponding proof-theoretic ordinal)?

Trending Questions

Popular # Hahtags

Popular Questions