A note on the T2-reflection of semitopological groups

被引:4
|
作者
Sanchez, Ivan
机构
关键词
Semitopological group; T-i-refiection; Open homomorphism; Feebly compact;
D O I
10.1016/j.topol.2014.12.020
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
Given a semitopological group G, denote by N(e) the family of open neighborhoods of the identity e in G. We show that K = boolean AND{(U) over bar : U is an element of N(e)} is a closed invariant subgroup of G. Therefore, the T-2-reflection of G is topologically isomorphic to G/K. Also, we show that in every semitopological group G, the following conditions are equivalent: i) G is feebly compact; ii) T-0(G) is feebly compact; iii) T-1(G) is feebly compact; iv) T-2(G) is feebly compact. These results answer some questions posed by M. Tkachenko about the T-i-reflection of semitopological groups, for i = 1, 2. (C) 2014 Elsevier B.V. All rights reserved.
引用
收藏
页码:117 / 121
页数:5
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