We study binormality, a separation property of spaces endowed with two topologies known in the real analysis as the Luzin-Menchoff property. The main object of our interest are Banach spaces with their norm and weak topologies. We show that every separable Banach space is binormal and the space $\ell^{\infty}$ is not binormal.
@article{118926, author = {Petr Holick\'y}, title = {Binormality of Banach spaces}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {38}, year = {1997}, pages = {279-282}, zbl = {0886.46012}, mrnumber = {1455495}, language = {en}, url = {http://dml.mathdoc.fr/item/118926} }
Holický, Petr. Binormality of Banach spaces. Commentationes Mathematicae Universitatis Carolinae, Tome 38 (1997) pp. 279-282. http://gdmltest.u-ga.fr/item/118926/
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