R. Matsuda has shown that a group ring is a Krull domain if and only if the coefficient ring is a Krull domain and the group is a torsion-free abelian group satisfying the ascending chain condition (ace) on cyclic subgroups [6]. D. F. Anderson has used this to obtain a partial determination of when a semigroup ring is a Krull domain, and under certain circumstances to describe the divisor class group of such a ring ([1], [2]). Using some of Anderson's techniques, but taking a different approach, we arrive at a complete answer of a different nature to these questions. We call a semigroup satisfying the major new conditions arising a Krull semigroup, and define its divisor class group.In particular, every abelian group is the divisor class group of such a ring, and it follows that every abelian group is the divisor class group of a quasi-local ring, which seems to be a new result.
@misc{10_4153_CJM_1981_112_x,
title = {Krull {Semigroups} and {Divisor} {Class} {Groups}},
journal = {Canadian journal of mathematics},
pages = {1459--1468},
year = {1981},
volume = {33},
number = {6},
doi = {10.4153/CJM-1981-112-x},
url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1981-112-x/}
}
TY - JOUR
TI - Krull Semigroups and Divisor Class Groups
JO - Canadian journal of mathematics
PY - 1981
SP - 1459
EP - 1468
VL - 33
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UR - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1981-112-x/
DO - 10.4153/CJM-1981-112-x
ID - 10_4153_CJM_1981_112_x
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%R 10.4153/CJM-1981-112-x
%F 10_4153_CJM_1981_112_x