Borel decomposition into an injective part and a countable-image part
Ascertain whether for every Borel function f between Polish zero-dimensional spaces there exists a Borel partition (A,B) of the domain such that the restriction f|A is continuously equivalent to an injection and the restriction f|B has countable image.
References
This was [Question 5.6] we upgrade it here to the status of conjecture, and we do the same for the next question.
Conjecture Given any Borel function f between Polish (zero-dimen-sional) spaces, there is a Borel partition (A,B) of dom f such that f{A} is continuously equivalent to an injection, and f{B} has countable image.
                — A well-quasi-order for continuous functions
                
                (2410.13150 - Carroy et al., 17 Oct 2024) in Section 7.3 (DirectionPolish)