A note on rank 2 diagonals


  • Angelo Bella University of Catania
  • Santi Spadaro University of Catania




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


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.


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Author Biographies

Angelo Bella, University of Catania

Dipartimento di Matematica e Informatica

Santi Spadaro, University of Catania

Dipartimento di Matematica e Informatica


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How to Cite

A. Bella and S. Spadaro, “A note on rank 2 diagonals”, Appl. Gen. Topol., vol. 21, no. 1, pp. 81–85, Apr. 2020.