English

Discrete orderings in the real spectrum

Logic 2019-03-12 v2

Abstract

We study discrete orderings in the real spectrum of a commutative ring by defining discrete prime cones and give an algebro-geometric meaning to some kind of diophantine problems over discretely ordered rings. Also for a discretely ordered ring MM and a real closed field RR containing MM we prove a theorem on the distribution of the discrete orderings of M[X1,,Xn]M[X_1,\dots,X_n] in \Spec(R[X1,,Xn])\Spec(R[X_1,\dots,X_n]) in geometric terms. To be more precise, we prove that any ball B(α,r)\mathbb{B}(\alpha,r) in \Spec(R[X1,,Xn]\Spec(R[X_1,\dots,X_n]) with center α\alpha and radius rr (defined via Robson's metric) contains a discrete ordering of M[X1,,Xn]M[X_1,\dots,X_n] whenever rr is non-infinitesimal and α\alpha is away from all hyperplanes over MM passing through the origin.

Keywords

Cite

@article{arxiv.1807.00501,
  title  = {Discrete orderings in the real spectrum},
  author = {Shahram Mohsenipour},
  journal= {arXiv preprint arXiv:1807.00501},
  year   = {2019}
}

Comments

Revised and refined

R2 v1 2026-06-23T02:47:46.441Z