Abstract
We show the existence of a subalgebra A⊆P(ω) that satisfies the following three conditions: A is Borel (when P(ω) is identified with 2ω). A is arithmetically closed (i.e., A is closed under the Turing jump, and Turing reducibility). The forcing notion (A,⊆) modulo the ideal FIN of finite sets collapses the continuum to א0.
Original language | English |
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Pages (from-to) | 2495-2502 |
Number of pages | 8 |
Journal | Topology and its Applications |
Volume | 158 |
Issue number | 18 |
DOIs | |
State | Published - 1 Dec 2011 |
Keywords
- Borel structure
- Completely separable family
- Forcing
- Tree indiscernible