English

A note on $\mathbb{Z}$ as a direct summand of nonstandard models of weak systems of arithmetic

Logic 2016-05-31 v1

Abstract

There are nonstandard models of normal open induction (NOINOI) for which Z\mathbb{Z} is a direct summand of their additive group. We show that this is impossible for nonstandard models of IE2IE_2.

Keywords

Cite

@article{arxiv.1605.09222,
  title  = {A note on $\mathbb{Z}$ as a direct summand of nonstandard models of weak systems of arithmetic},
  author = {Merlin Carl},
  journal= {arXiv preprint arXiv:1605.09222},
  year   = {2016}
}