Models of arithmetic and subuniform bounds for the arithmetic sets
A. H. Lachlan, Robert Irving Soare · Journal of Symbolic Logic · 1998
Abstract It has been known for more than thirty years that the degree of a non-standard model of true arithmetic is a subuniform upper bound for the arithmetic sets (suub). Here a notion of generic enumeration is presented with the property that the degree of such an enumeration is an suub but not the degree of a non-standard model of true arithmetic. This answers a question posed in the literature.