Countable Toronto spaces
نویسنده
چکیده
A space X is called an α-Toronto space if X is scattered of Cantor– Bendixson rank α and is homeomorphic to each of its subspaces of the same rank. We answer a question of Steprāns by constructing a countable α-Toronto space for each α ≤ ω. We also construct consistent examples of countable α-Toronto spaces for each
منابع مشابه
ar X iv : m at h / 99 02 07 1 v 1 [ m at h . G N ] 1 1 Fe b 19 99 COUNTABLE TORONTO SPACES
A space X is called an α-Toronto space if X is scattered of Cantor-Bendixson rank α and is homeomorphic to each of its subspaces of same rank. We answer a question of Steprans by constructing a countable α-Toronto space for each α ≤ ω. We also construct consistent examples of countable α-Toronto spaces for each α < ω 1 .
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تاریخ انتشار 2007