English

Egyptian integral domains

Commutative Algebra 2023-08-15 v2

Abstract

The notion of an Egyptian domain (where the analogue of Egyptian fractions works appropriately), first explored by Guerrieri-Loper-Oman, is extended to the more general notions of generically and locally Egyptian domains. Results from the previous paper are extended, as well as reinterpreted in the new expanded context. It is shown that localizations of polynomial rings are typically Egyptian, that positive semigroup-graded domains are not Egyptian, and that affine semigroup rings are not Egyptian unless the semigroup is a group. However, any finitely generated algebra over a field or Z\mathbb Z is shown to be locally Egyptian. It is further shown that if RR is a pullback of SS, then RR is Egyptian if and only if SS is.

Keywords

Cite

@article{arxiv.2303.15685,
  title  = {Egyptian integral domains},
  author = {Neil Epstein},
  journal= {arXiv preprint arXiv:2303.15685},
  year   = {2023}
}

Comments

Some minor errors corrected and points clarified, due to referee comments. 10 pages

R2 v1 2026-06-28T09:37:04.212Z