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Popopo
  • Member for 12 years
  • Last seen more than 3 years ago
24 votes
2 answers
2k views

Hyperreal measure?

15 votes
2 answers
2k views

Can proper classes also have cardinality?

10 votes
3 answers
1k views

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

10 votes
1 answer
2k views

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

10 votes
3 answers
1k views

What is straight line?

8 votes
1 answer
2k views

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

8 votes
2 answers
152 views

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

8 votes
2 answers
374 views

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

8 votes
2 answers
466 views

Is there any countable ordinal number which has a member undefinable?

7 votes
1 answer
1k views

Which side has winning strategy in Go?

7 votes
2 answers
2k views

How many partial order on a n-set? [duplicate]

7 votes
2 answers
1k views

Fractional calculus in complex analysis

7 votes
3 answers
2k views

Which set is unwell-orderable?

7 votes
2 answers
5k views

Do $\omega^\omega=2^{\aleph_0}=\aleph_1$?

7 votes
1 answer
996 views

Cardinality of the set of ultrafilters on an infinite Boolean algebra

6 votes
2 answers
152 views

What's the name of this operator?

6 votes
4 answers
489 views

Is probability objective?

6 votes
2 answers
603 views

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

6 votes
4 answers
2k views

Are there rules in the useage of prepositions in Math?

5 votes
1 answer
546 views

Do filters on a Boolean algebra also make a Boolean algebra?

5 votes
1 answer
275 views

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

4 votes
1 answer
338 views

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

4 votes
1 answer
166 views

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

4 votes
0 answers
425 views

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

4 votes
2 answers
463 views

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

4 votes
1 answer
8k views

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

4 votes
1 answer
809 views

Does elementary embedding exist between two elementary equivalent structures?

3 votes
1 answer
227 views

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

3 votes
1 answer
221 views

What's correspondence between the model theoric and the set theoric kernel of homomorphism?

3 votes
2 answers
65 views

Is operator open at topological groups?