Rafał Gruszczyński's user avatar
Rafał Gruszczyński's user avatar
Rafał Gruszczyński's user avatar
Rafał Gruszczyński
  • Member for 12 years
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11 votes
1 answer
427 views

A strictly descending chain of subalgebras of $P(\omega)/_{\mathrm{fin}}$

8 votes
2 answers
286 views

Does $\aleph_0$-density of regular open algebra entail existence of countable basis?

7 votes
1 answer
638 views

(Finite) Models of two subtheories of Peano Arithmetic

5 votes
1 answer
246 views

Convergent filters generated by (not necessarily countable) chains

5 votes
1 answer
167 views

(A kind of) Irreducibiliy of regular open convex sets in the Cartesian space

5 votes
1 answer
309 views

A problem of non-emptiness of intersections of certain chains of regular open sets

4 votes
1 answer
388 views

Is normality of a Hausdorff space consequence of some property of open domains?

3 votes
1 answer
440 views

An example of a regular but not linear-based topological space

2 votes
2 answers
435 views

An example of a frame homomorphism which does not preserve Heyting implication

2 votes
2 answers
235 views

Special filters in the algebra of regular open sets of a topological space

2 votes
1 answer
301 views

Boolean algebras and free filters generated by chains

2 votes
1 answer
143 views

Regular open Boolean algebras and homomorphism which does not preserve nearness of sets

2 votes
0 answers
362 views

The theory of frames and locales as elementary topology [closed]

1 vote
1 answer
138 views

Intersections of families of open sets ordered by well-inside relation in Euclidean space

1 vote
2 answers
710 views

An interpretation of not-Con(PA)

0 votes
1 answer
158 views

Existence of half-planes with respect to regular open sets of the Euclidean plane