English

A new dp-minimal expansion of the integers

Logic 2019-06-12 v2

Abstract

We consider the structure (Z,+,0,p1,,pn)(\mathbb{Z},+,0,|_{p_{1}},\dots,|_{p_{n}}), where xpyx|_{p}y means vp(x)vp(y)v_{p}(x)\leq v_{p}(y) and vpv_p is the pp-adic valuation. We prove that its theory has quantifier elimination in the language {+,,0,1,(Dm)m1,p1,,pn}\{+,-,0,1,(D_{m})_{m\geq1},|_{p_{1}},\dots,|_{p_{n}}\} where Dm(x)y my=xD_m(x)\leftrightarrow \exists y ~ my = x, and that it has dp-rank nn. In addition, we prove that a first order structure with universe Z\mathbb{Z} which is an expansion of (Z,+,0)(\mathbb{Z},+,0) and a reduct of (Z,+,0,p)(\mathbb{Z},+,0,|_{p}) must be interdefinable with one of them. We also give an alternative proof for Conant's analogous result about (Z,+,0,<)(\mathbb{Z},+,0,<).

Keywords

Cite

@article{arxiv.1707.07203,
  title  = {A new dp-minimal expansion of the integers},
  author = {Eran Alouf and Christian d'Elbée},
  journal= {arXiv preprint arXiv:1707.07203},
  year   = {2019}
}

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24 pages