Wadge Hierarchy and Veblen Hierarchy. Part II: Borel Sets of Infinite Rank
submitted to the Journal of Symbolic Logic
We consider Borel sets of the form A ⊆ Λω (with usual topology) where cardinality of Λ is less than some uncountable regular cardinal Κ. We obtain a ``normal form'' of A, by finding a Borel set Ω(α) such that A and Ω(α) continuously reduce to each other. We do so by defining Borel operations which are homomorphic to the Κ first Veblen ordinal functions of base Κ required to compute the Wadge degree of the set A: the ordinal α.
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