Apparently in a topological space, the property of being normal (can separate closed sets) is not productive.
What is an example of such a space? In other words, normal spaces $X$ and $Y$ such that $X\times Y$ is not normal.
Apparently in a topological space, the property of being normal (can separate closed sets) is not productive.
What is an example of such a space? In other words, normal spaces $X$ and $Y$ such that $X\times Y$ is not normal.