We show that a (weakly) Whyburn space $X$ may be mapped continuously via an open map $f$ onto a non (weakly) Whyburn space $Y$. This fact may happen even between topological groups $X$ and $Y$, $f$ a homomorphism, $X$ Whyburn and $Y$ not even weakly Whyburn.
@article{119406,
author = {Franco Obersnel},
title = {Open maps do not preserve Whyburn property},
journal = {Commentationes Mathematicae Universitatis Carolinae},
volume = {44},
year = {2003},
pages = {525-530},
zbl = {1098.54008},
mrnumber = {2025818},
language = {en},
url = {http://dml.mathdoc.fr/item/119406}
}
Obersnel, Franco. Open maps do not preserve Whyburn property. Commentationes Mathematicae Universitatis Carolinae, Tome 44 (2003) pp. 525-530. http://gdmltest.u-ga.fr/item/119406/
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