Strong colorings yield $\kappa$-bounded spaces with discretely untouchable points

Abstract:

It is well known that every non-isolated point in a compact Hausdorff space is the accumulation point of a discrete subset. Answering a question raised by Z. Szentmiklóssy and the first author, we show that this statement fails for countably compact regular spaces, and even for $\omega$-bounded regular spaces. In fact, there are $\kappa$-bounded counterexamples for every infinite cardinal $\kappa$. The proof makes essential use of the so-called strong colorings that were invented by the second author.