On PCF spaces which are not Frechet-Urysohn

Juan Carlos Martínez

Abstrakt

By means of a forcing argument, it was shown by Pereira that if CH holds then there is a separable PCF space of height w1 + 1 which is not Frechet-Urysohn. In this paper, we give a direct proof of Pereira's theorem by means of a forcing-free argument, and we extend his result to PCF spaces of any height  + 1 where  < w2 with cf() = w1.

Słowa kluczowe: PCF space, Sequentiality, Frechet-Urysohn property.
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