A note on rank 2 diagonals

Angelo Bella, Santi Spadaro

Abstract

We solve two questions regarding spaces with a (Gδ)-diagonal of rank 2. One is a question of Basile, Bella and Ridderbos about weakly Lindelöf spaces with a Gδ-diagonal of rank 2 and the other is a question of Arhangel’skii and Bella asking whether every space with a diagonal of rank 2 and cellularity continuum has cardinality at most continuum.


Keywords

cardinality bounds; weakly Lindelöf; Gδ-diagonal; neighbourhood assignment; dual properties

Subject classification

54D10; 54A25

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References

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