Wyniki wyszukiwania

1

Separating by $G_{δ}$-sets in finite powers of ω₁

100%

Hirata Y., Kemoto N.

Fundamenta Mathematicae

|

2003

|

tom 177

|

nr 1

83-94

EN

It is known that all subspaces of ω₁² have the property that every pair of disjoint closed sets can be separated by disjoint $G_{δ}$-sets (see [4]). It has been conjectured that all subspaces of ω₁ⁿ also have this property for each n < ω. We exhibit a subspace of {⟨α,β,γ⟩ ∈ ω₁³: α ≤ β ≤ γ} which does not have this property, thus disproving the conjecture. On the other hand, we prove that all subspaces of {⟨α,β,γ⟩ ∈ ω₁³: α < β < γ} have this property.

2

Normal subspaces in products of two ordinals

81%

Kemoto N., Nogura T., Smith K. D., Yajima Y.

Fundamenta Mathematicae

|

1996

|

tom 151

|

nr 3

279-297

EN

Let λ be an ordinal number. It is shown that normality, collectionwise normality and shrinking are equivalent for all subspaces of $(λ+1)^2$.

3

The shrinking property and the B-property in ordered spaces

70%

Kemoto N.

Fundamenta Mathematicae

|

1990

|

tom 134

|

nr 3

255-261

4

The shrinking property of products of cardinals

50%

Kemoto N.

Fundamenta Mathematicae

|

1991

|

tom 137

|

nr 1

59-63

5

Subparacompactness in locally nice spaces

50%

Kemoto N.

Fundamenta Mathematicae

|

1989

|

tom 132

|

nr 2

163-169

6

Collectionwise Hausdorffness at limit cardinals

50%

Kemoto N.

Fundamenta Mathematicae

|

1991

|

tom 138

|

nr 1

59-67

Ograniczanie wyników

6 Fundamenta Mathematicae

6 Kemoto N.

1 Hirata Y.

1 Nogura T.

1 Smith K. D.

1 Yajima Y.

1 2003

1 1996

2 1991

1 1990

1 1989

Separating by $G_{δ}$-sets in finite powers of ω₁

Normal subspaces in products of two ordinals

The shrinking property and the B-property in ordered spaces

The shrinking property of products of cardinals

Subparacompactness in locally nice spaces

Collectionwise Hausdorffness at limit cardinals