Equality of T"(X) and T'(X) beyond perfectly normal spaces
Determine whether there exists a topological space X that is not perfectly normal yet satisfies T"(X) = T'(X), where T"(X) is the ring of real-valued functions on X that are continuous on a dense cozero set and T'(X) is the ring of real-valued functions on X that are continuous on an open dense subset.
References
Whether there exists a topological space outside the class of perfectly normal spaces for which T"(X) = T'(X) remains an unanswered question.
                — The ring of real-valued functions which are continuous on a dense cozero set
                
                (2502.15358 - Dey et al., 21 Feb 2025) in Remark 2.9, Section 2