The Alexandroff Duplicate and its subspaces

Agata Caserta, Stephen Watson


We study some topological properties of the class of the Alexandroff duplicates and their subspaces. We give a characterization of metrizability and Lindel¨of properties of subspaces of the Alexandroff duplicate. This characterization clarifies the potential for finding Michael spaces among the subspaces of Alexandroff duplicates.


Resolution; Alexandroff duplicate; Lindelöf property; Michaeltype line

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doi: 10.1007/s00009-011-0162-4

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