User Popopo - Mathematics Stack Exchange

bio	website
	location	Pop Star, MathCraft
	age
visits	member for	11 months
	seen	1 hour ago
stats	profile views	217

	609 reputation	bio	website		visits	member for	11 months
226 badges		location	Pop Star, MathCraft		seen	1 hour ago

2

11

votes

2

answers

268

views

Hyperreal measure?

mar 1 at 5:26 Popopo 609

1

8

votes

2

answers

98

views

Can we conclude $\prod_{\kappa \in Crd, \kappa=1}^{\kappa<\aleph_\alpha}\kappa=2^{\aleph_\alpha}$ in ZFC?

elementary-set-theory cardinals

apr 16 at 13:31 Andres Caicedo 24.4k

1

7

votes

4

answers

370

views

What is straight line?

geometry metric-spaces definition philosophy

nov 26 at 6:14 Yury 3,358

5

7

votes

2

answers

347

views

Fractional calculus in complex analysis

complex-analysis fractional-calculus

sep 30 at 18:36 vesszabo 1,428

6

votes

4

answers

140

views

Are there rules in the useage of prepositions in Math?

soft-question terminology article-writing

mar 30 at 18:09 amWhy 54.1k

6

votes

2

answers

119

views

How many partial order on a n-set?

combinatorics open-problem

nov 8 at 3:12 Popopo 609

6

votes

4

answers

259

views

Is probability objective?

probability probability-theory information-theory philosophy

sep 27 at 3:46 Popopo 609

1

6

votes

2

answers

117

views

What's the name of this operator?

abstract-algebra set-theory category-theory model-theory

jun 9 '12 at 14:40 Henning Makholm 53.5k

5

votes

2

answers

102

views

Can proper classes also have cardinality?

set-theory cardinals

mar 22 at 8:01 Popopo 609

2

5

votes

1

answer

134

views

Can an infinite cardinal number be a sum of two smaller cardinal number?

set-theory cardinals axiom-of-choice infinity

nov 10 at 11:23 Asaf Karagila 90.5k

5

votes

1

answer

159

views

Could Residue theorem be seen as a special case of Stokes' theorem?

calculus complex-analysis differential-forms

sep 19 at 13:46 David Speyer 18.6k

1

4

votes

1

answer

71

views

Which logic is stronger? SOL or $\frak{L}_{\infty,\infty}$?

logic model-theory

apr 27 at 15:19 Peter Smith 11.3k

4

votes

0

answers

96

views

What is the correspondence between the semantic compactness of logics and the compactness of Stone spaces?

logic model-theory

mar 27 at 19:33 Popopo 609

4

votes

1

answer

255

views

Does Black have a winning strategy in Gomoku(freestyle)?

computational-complexity game-theory

jan 20 at 9:53 joriki 92.2k

4

votes

1

answer

99

views

Is this theory $\kappa$-categorical when $\kappa$ is infinite and not $\le \aleph_0$?

logic cardinals axiom-of-choice model-theory

dec 1 at 15:19 Asaf Karagila 90.5k

1

4

votes

1

answer

79

views

Is $\aleph_0$ the minimum infinite cardinal number in $ZF$?

elementary-set-theory cardinals axiom-of-choice infinity

nov 29 at 10:55 Asaf Karagila 90.5k

2

4

votes

2

answers

204

views

Are the Join and Meet operators on complete lattices both continuous?

limit order-theory lattice-orders

nov 5 at 16:59 Popopo 609

2

4

votes

1

answer

116

views

Prove/Disprove $f$ continuous iff $f[\mathring{A}]\supseteq\mathring{f[A]}$

homework general-topology

sep 26 at 11:26 Kevin Carlson 3,494

3

votes

2

answers

54

views

On models of ZFC, does there exist a bijection between Von Neumann universe and the ordinal class?

set-theory

mar 21 at 15:45 Brian M. Scott 154k

1

3

votes

2

answers

203

views

Proving that for infinite $\kappa$, $|[\kappa]^\lambda|=\kappa^\lambda$

set-theory cardinals

mar 14 at 12:24 Popopo 609

1

3

votes

1

answer

239

views

Which side has winning strategy in Go?

game-theory open-problem

dec 27 at 19:22 Ed Pegg 2,066

3

votes

3

answers

215

views

Which set is unwell-orderable?

elementary-set-theory cardinals axiom-of-choice ordinals

sep 19 at 12:13 Asaf Karagila 90.5k

3

votes

1

answer

160

views

Cardinality of the set of ultrafilters on an infinite Boolean algebra

combinatorics set-theory order-theory boolean-algebra lattice-orders

jun 8 '12 at 19:33 Asaf Karagila 90.5k

2

votes

2

answers

61

views

What's the remainder of a natual number divided by lcm(m,n)?

elementary-number-theory

apr 6 at 8:17 Popopo 609

2

votes

1

answer

48

views

How to deal with infinite continued fractions in formal language?

logic continued-fractions

apr 6 at 0:21 Henning Makholm 53.5k

1

2

votes

2

answers

47

views

How to extend definition of n-tuple to the case $n=0$?

elementary-set-theory definition

mar 22 at 16:42 Arthur Fischer 21.3k

2

votes

1

answer

69

views

Is $\kappa^\lambda=2^\lambda$($2 \le \kappa<\lambda$,$\lambda$ infinite) valid in set models of ZF?

elementary-set-theory cardinals axiom-of-choice

mar 21 at 10:10 P.. 8,850

1

2

votes

1

answer

50

views

Is every homomorphism from $\langle(0,+\infty),\,\cdot\,,{}^{-1}\rangle$ into $\langle\{-1,1\},\,\cdot\,,{}^{-1}\rangle$ a constant valued function?

group-theory

jan 26 at 7:42 Zev Chonoles♦ 53.1k

2

votes

2

answers

164

views

Is the negation of Gödel's completeness theorem consistent with $ZF$ without AC?

logic axiom-of-choice model-theory compactness

nov 27 at 19:13 Asaf Karagila 90.5k

2

votes

1

answer

79

views

In topological groups. Is every neighborhood of $e$ supset of a square of a symmetric neighborhood of $e$?

homework topological-groups

nov 10 at 12:37 Popopo 609

Popopo

58 Questions