No hedgehog in the product?
Simon, Petr ; Tironi, Gino
Commentationes Mathematicae Universitatis Carolinae, Tome 43 (2002), p. 349-361 / Harvested from Czech Digital Mathematics Library
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Assuming OCA, we shall prove that for some pairs of Fréchet $\alpha_4$-spaces $X, Y$, the Fréchetness of the product $X\times Y$ implies that $X\times Y$ is $\alpha_4$. Assuming MA, we shall construct a pair of spaces satisfying the assumptions of the theorem.

Publié le : 2002-01-01
Classification:  03E50,  03E65,  54B10,  54D55,  54G20 
@article{119325,
     author = {Petr Simon and Gino Tironi},
     title = {No hedgehog in the product?},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {43},
     year = {2002},
     pages = {349-361},
     zbl = {1090.54024},
     mrnumber = {1922133},
     language = {en},
     url = {http://dml.mathdoc.fr/item/119325}
}

Simon, Petr; Tironi, Gino. No hedgehog in the product?. Commentationes Mathematicae Universitatis Carolinae, Tome 43 (2002) pp. 349-361. http://gdmltest.u-ga.fr/item/119325/

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