1-Genericity Is Not Weihrauch Reducible to the Finite Intersection Principle
Patrizio Cintioli
Abstract
This paper shows that the problem of producing a Cohen 1-generic real relative to a given oracle is not Weihrauch reducible to the finite intersection principle (FIP). More strongly, no nontrivial computable FIP instance admits a single Turing functional that produces an absolute 1-generic real from every enumeration of every maximal centered set of indices. The argument combines a 1-generic real that computes no perfect tree all of whose paths are 1-generic with local constancy and a parametrization of maximal centered sets. This answers Question~9.10.25 of Dzhafarov and Mummert.
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