English

Big projective modules over noetherian semilocal rings

Rings and Algebras 2009-03-18 v1

Abstract

We prove that for a noetherian semilocal ring RR with exactly kk isomorphism classes of simple right modules the monoid V(R)V^*(R) of isomorphism classes of countably generated projective right (left) modules, viewed as a submonoid of V(R/J(R))V^*(R/J(R)), is isomorphic to the monoid of solutions in (\No{})k(\No \cup\{\infty\})^k of a system consisting of congruences and diophantine linear equations. The converse also holds, that is, if MM is a submonoid of (\No{})k(\No \cup\{\infty\})^k containing an order unit (n1,...,nk)(n_1,..., n_k) of \Nok\No^k which is the set of solutions of a system of congruences and linear diophantine equations then it can be realized as V(R)V^*(R) for a noetherian semilocal ring such that R/J(R)Mn1(D1)×...×Mnk(Dk)R/J(R)\cong M_{n_1}(D_1)\times ... \times M_{n_k}(D_k) for suitable division rings D1,...,DkD_1,..., D_k.

Keywords

Cite

@article{arxiv.0903.2965,
  title  = {Big projective modules over noetherian semilocal rings},
  author = {Dolors Herbera and Pavel Prihoda},
  journal= {arXiv preprint arXiv:0903.2965},
  year   = {2009}
}

Comments

41 pages

R2 v1 2026-06-21T12:41:32.524Z