Generically Computable Linear Orderings

التفاصيل البيبلوغرافية
العنوان: Generically Computable Linear Orderings
المؤلفون: Calvert, Wesley, Cenzer, Douglas, Gonzalez, David, Harizanov, Valentina
سنة النشر: 2024
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Logic
الوصف: We study notions of generic and coarse computability in the context of computable structure theory. Our notions are stratified by the $\Sigma_\beta$ hierarchy. We focus on linear orderings. We show that at the $\Sigma_1$ level all linear orderings have both generically and coarsely computable copies. This behavior changes abruptly at higher levels; we show that at the $\Sigma_{\alpha+2}$ level for any $\alpha\in\omega_1^{ck}$ the set of linear orderings with generically or coarsely computable copies is $\mathbf{\Sigma}_1^1$-complete and therefore maximally complicated. This development is new even in the general analysis of generic and coarse computability of countable structures. In the process of proving these results we introduce new tools for understanding generically and coarsely computable structures. We are able to give a purely structural statement that is equivalent to having a generically computable copy and show that every relational structure with only finitely many relations has coarsely and generically computable copies at the lowest level of the hierarchy.
Comment: 35 pages
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2401.14598
رقم الأكسشن: edsarx.2401.14598
قاعدة البيانات: arXiv