English

Higher dimensional Teter rings

Commutative Algebra 2025-01-24 v1

Abstract

Let (A,m)(A,\mathfrak{m}) be a complete Cohen-Macaulay local ring. Assume AA is not Gorenstein. We say AA is a Teter ring if there exists a complete Gorenstein ring (B,n)(B,\mathfrak{n}) with dimB=dimA\dim B = \dim A and a surjective map BAB \rightarrow A with e(B)e(A)=1e(B) - e(A) = 1 (here e(A)e(A) denotes multiplicity of AA). We give an intrinsic characterization of Teter rings which are domains. We say a Teter ring is a strongly Teter ring if G(B)=i0ni/ni+1G(B) = \bigoplus_{i \geq 0}\mathfrak{n}^i/\mathfrak{n}^{i+1} is also a Gorenstein ring. We give an intrinsic characterizations of strongly Teter rings which are domains. If kk is algebraically closed field of characteristic zero and RR is a standard graded Cohen-Macaulay kk-algebra of finite representation type (and not Gorenstein) then we show that RM^\widehat{R_\mathfrak{M}} is a Teter ring (here M\mathfrak{M} is the maximal homogeneous ideal of RR).

Keywords

Cite

@article{arxiv.2501.13526,
  title  = {Higher dimensional Teter rings},
  author = {Tony J. Puthenpurakal},
  journal= {arXiv preprint arXiv:2501.13526},
  year   = {2025}
}
R2 v1 2026-06-28T21:14:37.537Z