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Cardinality bound for Urysohn spaces with an H-closed π-base using wL, t, and ψ_c

Determine whether the cardinality inequality |X| ≤ 2^{wL(X) t(X) ψ_c(X)} holds for every Urysohn Hausdorff topological space X that admits a π-base whose elements have H-closed closures.

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Background

The paper studies cardinal bounds for spaces with a π-base whose elements have H-closed closures. For quasiregular spaces in this class, Carlson establishes |X| ≤ 2{wL(X) t(X) ψ_c(X)}. For Urysohn spaces, the authors prove a different bound |X| ≤ 2{wL(X) k(X)}, where k(X) is a cardinal function introduced by Alas and Kocinac, and present examples showing k(X) may be strictly smaller than χ(X). Whether the stronger inequality with t(X) and ψ_c(X) also holds for Urysohn spaces remains explicitly questioned by the authors.

References

Question 1.5. Does the inequality |X| ≤ 2 wL(X)t(X)c (X)hold for Urysohn spaces having an H-closed π-base?

On spaces with a $π$-base whose elements have an H-closed closure (2401.17160 - Giacopello, 30 Jan 2024) in Question 1.5, Section 1 (Introduction)