English

Scott sentence complexities of linear orderings

Logic 2026-02-11 v1

Abstract

We study possible Scott sentence complexities of linear orderings using two approaches. First, we investigate the effect of the Friedman-Stanley embedding on Scott sentence complexity and show that it only preserves Παin\Pi^{\mathrm{in}}_{\alpha} complexities. We then take a more direct approach and exhibit linear orderings of all Scott complexities except Σ3in\Sigma^{\mathrm{in}}_{3} and Σλ+1in\Sigma^{\mathrm{in}}_{\lambda+1} for λ\lambda a limit ordinal. We show that the former can not be the Scott sentence complexity of a linear ordering. In the process we develop new techniques which appear to be helpful to calculate the Scott sentence complexities of structures.

Cite

@article{arxiv.2305.07126,
  title  = {Scott sentence complexities of linear orderings},
  author = {David Gonzalez and Dino Rossegger},
  journal= {arXiv preprint arXiv:2305.07126},
  year   = {2026}
}
R2 v1 2026-06-28T10:32:28.931Z