| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4661831 | Annals of Pure and Applied Logic | 2015 | 15 Pages |
Abstract
A normal measure U on a measurable cardinal κ cannot be definable over H(κ+)H(κ+), as otherwise it would belong to its own ultrapower. In this article we show that it may however be Δ1Δ1 definable over H(κ++)H(κ++) when the GCH fails at κ. In [7] it is shown that there can be a unique normal measure on κ when the GCH fails at κ ; we show here that this unique normal measure can in addition be Δ1Δ1 definable over H(κ++)H(κ++).
Keywords
Related Topics
Physical Sciences and Engineering
Mathematics
Logic
Authors
Sy-David Friedman, Liuzhen Wu,