Cohesive Powers of Linear Orders
Logic
2019-08-28 v1
Abstract
Cohesive powers of computable structures can be viewed as effective ultraproducts over effectively indecomposable sets called cohesive sets. We investigate the isomorphism types of cohesive powers for familiar computable linear orders . If is isomorphic to the ordered set of natural numbers and has a computable successor function, then is isomorphic to Here, stands for the sum and for the lexicographical product of two orders. We construct computable linear orders and isomorphic to both with noncomputable successor functions, such that is isomorphic to , while is not While cohesive powers preserve all and sentences, we provide new examples of sentences and computable structures such that while
Cite
@article{arxiv.1901.04786,
title = {Cohesive Powers of Linear Orders},
author = {Rumen Dimitrov and Valentina Harizanov and Andrey Morozov and Paul Shafer and Alexandra Soskova and Stefan Vatev},
journal= {arXiv preprint arXiv:1901.04786},
year = {2019}
}