An example of a compact space of uncountable character for which the space exp (n) (X) \ X is normal

作者：Ivanov A V^*

来源：Mathematical Notes, 2015, 98(1-2): 251-257.

DOI：10.1134/S0001434615070263

• Katetov's theorem
• square of a compact space
• first-countable compact space
• functor exp(n)
• Jensen's axiom
• normal functor

Under Jensen's axiom, a compact space X of uncountable character such that the space exp (n) (X) \ X is normal for each n is constructed. Thereby, it is proved that the Arkhangel'skii-Kombarov theorem on the countability of the character of a compact space whose square is normal outside the diagonal cannot be "na < vely" carried over to normal functors of finite degree.

• 出版日期2015-7