Preservation of Point Properties Under Refinable Maps

Determine whether each of the continuum properties \(\mathcal{P}_2\), \(\mathcal{P}_3\), \(\mathcal{P}_5\), and \(\mathcal{P}_6\) is preserved under refinable maps, where \(\mathcal{P}_i\) means that every point has the corresponding point property \(\mathbf{P}_i\): non-weak cut point, non-block point, non-strong center point, or non-cut point, respectively.

Background

The paper studies preservation of several global continuum properties under refinable maps. It establishes that P4\mathcal{P}_4, the property that every point is a shore point, is preserved under refinable maps, and recalls that P1\mathcal{P}_1, colocal connectedness, is also preserved. The corresponding preservation question remains unresolved for the intermediate and terminal properties P2\mathcal{P}_2, P3\mathcal{P}_3, P5\mathcal{P}_5, and P6\mathcal{P}_6.

References

Let $i\in {2,3,5,6}$. Is $\mathcal{P}_i$ preserved under refinable maps?

— Whitney Properties and Whitney reversible properties of Cut and Non-Cut Points  (2609.31034 - Matsuhashi, 25 Sep 2026) in Section 3, immediately following Theorem 3.1