English

Ideal class groups of monoid algebras

Commutative Algebra 2015-05-21 v2

Abstract

Let ABA\subset B be an extension of commutative reduced rings and MNM\subset N an extension of positive commutative cancellative torsion-free monoids. We prove that AA is subintegrally closed in BB and MM is subintegrally closed in NN if and only if the group of invertible AA-submodules of BB is isomorphic to the group of invertible A[M]A[M]-submodules of B[N]B[N]. In case M=NM=N, we prove the same without the assumption that the ring extension is reduced.

Keywords

Cite

@article{arxiv.1409.0299,
  title  = {Ideal class groups of monoid algebras},
  author = {Husney Parvez Sarwar},
  journal= {arXiv preprint arXiv:1409.0299},
  year   = {2015}
}

Comments

Title is changed. Main theorem is improved significantly, viz, relative version of monoid is considered. Final version is going to appear in Journal of Commutative Algebra

R2 v1 2026-06-22T05:45:11.717Z