Automorphisms, Mahlo Cardinals, and NFU
نویسندگان
چکیده
منابع مشابه
A Model of the Generic Vopěnka Principle in Which the Ordinals Are Not ∆2-mahlo
The generic Vopěnka principle, we prove, is relatively consistent with the ordinals being non-Mahlo. Similarly, the generic Vopěnka scheme is relatively consistent with the ordinals being definably non-Mahlo. Indeed, the generic Vopěnka scheme is relatively consistent with the existence of a ∆2definable class containing no regular cardinals. In such a model, there can be no Σ2-reflecting cardin...
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