English

Poincar\'e series of modules over compressed Gorenstein local rings

Commutative Algebra 2014-03-27 v3

Abstract

Given positive integers e and s we consider Gorenstein Artinian local rings R of embedding dimension e whose maximal ideal m\mathfrak{m} satisfies ms0=ms+1\mathfrak{m}^s\ne 0=\mathfrak{m}^{s+1}. We say that R is a compressed Gorenstein local ring when it has maximal length among such rings. It is known that generic Gorenstein Artinian algebras are compressed. If s3s\ne 3, we prove that the Poincare series of all finitely generated modules over a compressed Gorenstein local ring are rational, sharing a common denominator. A formula for the denominator is given. When s is even this formula depends only on the integers e and s. Note that for s=3s=3 examples of compressed Gorenstein local rings with transcendental Poincare series exist, due to B{\o}gvad.

Keywords

Cite

@article{arxiv.1211.6514,
  title  = {Poincar\'e series of modules over compressed Gorenstein local rings},
  author = {Maria Evelina Rossi and Liana M Şega},
  journal= {arXiv preprint arXiv:1211.6514},
  year   = {2014}
}

Comments

revised version, to appear in Adv. Math