Abstract
We present some results about generics for computable Mathias forcing. The n-generics and weak n-generics in this setting form a strict hierarchy as in the case of Cohen forcing. We analyze the complexity of the Mathias forcing relation, and show that if G is any n-generic with n ≥ 3 then it satisfies the jump property G (n − 1) = G′ ⊕ ∅ (n). We prove that every such G has generalized high degree, and so cannot have even Cohen 1-generic degree. On the other hand, we show that G, together with any bi-immune A ≤ T ∅ (n − 1), computes a Cohen n-generic.
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Cholak, P.A., Dzhafarov, D.D., Hirst, J.L. (2012). On Mathias Generic Sets. In: Cooper, S.B., Dawar, A., Löwe, B. (eds) How the World Computes. CiE 2012. Lecture Notes in Computer Science, vol 7318. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-30870-3_14
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DOI: https://doi.org/10.1007/978-3-642-30870-3_14
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