Abstract
We extend results found by Greenberg, Turetsky and Westrick in [7] and investigate effective properties of bases of uncountable free abelian groups. Assuming V = L, we show that if κ is a regular uncountable cardinal and X is a Δ11Lκ subset of κ, then there is a κ-computable free abelian group whose bases cannot be effectively computed by X. Unlike in [7], we give a direct construction.
| Original language | English |
|---|---|
| Title of host publication | Higher Recursion Theory and Set Theory |
| Publisher | World Scientific Publishing Co. |
| Pages | 71-85 |
| Number of pages | 15 |
| ISBN (Electronic) | 9789819806584 |
| ISBN (Print) | 9789819806577 |
| DOIs | |
| State | Published - 1 Jan 2025 |
Bibliographical note
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