English

Cohen Generic Structures with Functions

Logic 2024-06-06 v2

Abstract

Suppose LL\mathscr{L}^-\subseteq \mathscr{L} are languages where LL\mathscr{L} \setminus\mathscr{L}^- is relational. Additionally, let K\mathbf{K} be a strong Frai¨sseˊ\textrm{Fra\"iss\'e} class in L\mathscr{L}. We consider the partial ordering, under substructure, of those elements in K\mathbf{K} whose reduct to L\mathscr{L}^- are substructures of a fixed L\mathscr{L}^--structure M\mathcal{M}^-. In this paper, we establish that, under general conditions, this partial order satisfies the M|\mathcal{M}^-|-chain condition. Furthermore, under these conditions, we demonstrate that any generic for such a partial order satisfies the theory of the \Fraisse\ limit of K\mathbf{K}, provided M\mathcal{M}^- satisfies the theory ofFrai¨sseˊ\textrm{Fra\"iss\'e} limit of its age. We also provide general conditions that guarantee all such generics to be rigid, as well as conditions ensuring that these generics possess large automorphism groups.

Cite

@article{arxiv.2310.11582,
  title  = {Cohen Generic Structures with Functions},
  author = {Nathanael Ackerman and Mohammad Golshani and Mostafa Mirabi},
  journal= {arXiv preprint arXiv:2310.11582},
  year   = {2024}
}
R2 v1 2026-06-28T12:53:50.336Z