We observe that the characterization of rings of constants of derivations in characteristic zero as algebraically closed subrings also holds in positive characteristic after some natural adaptation. We also present a characterization of such rings in terms of maximality in some families of rings.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-cm122-2-9,
author = {Piotr J\k edrzejewicz},
title = {A note on rings of constants of derivations in integral domains},
journal = {Colloquium Mathematicae},
volume = {122},
year = {2011},
pages = {241-245},
zbl = {1221.13040},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm122-2-9}
}
Piotr Jędrzejewicz. A note on rings of constants of derivations in integral domains. Colloquium Mathematicae, Tome 122 (2011) pp. 241-245. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm122-2-9/