Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8904268 | Annals of Pure and Applied Logic | 2018 | 21 Pages |
Abstract
Using a modification of the invariant Jensen forcing of [11], we define a model of ZFC, in which, for a given nâ¥3, there exists a lightface Î n1-set of reals, which is a E0-equivalence class, hence a countable set, and which does not contain any OD element, while every non-empty countable Σn1-set of reals is constructible, hence contains only OD reals.
Related Topics
Physical Sciences and Engineering
Mathematics
Logic
Authors
Vladimir Kanovei, Vassily Lyubetsky,