Countable tightness and $${\mathfrak {G}}$$-bases on free topological groups

Autor: Jing Zhang, Alex Ravsky, Fucai Lin
Rok vydání: 2020
Předmět:
Zdroj: Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas. 114
ISSN: 1579-1505
1578-7303
Popis: Given a Tychonoff space $X$, let $F(X)$ and $A(X)$ be respectively the free topological group and the free Abelian topological group over $X$ in the sense of Markov. In this paper, we consider two topological properties of $F(X)$ or $A(X)$, namely the countable tightness and $\mathfrak G$-base. We provide some characterizations of the countable tightness and $\mathfrak G$-base of $F(X)$ and $A(X)$ for various special classes of spaces $X$. Furthermore, we also study the countable tightness and $\mathfrak G$-base of some $F_{n}(X)$ of $F(X)$.
Comment: 11
Databáze: OpenAIRE