English

Ideals with componentwise linear powers

Commutative Algebra 2025-02-12 v1 Combinatorics

Abstract

Let S=K[x1,,xn]S=K[x_1,\ldots,x_n] be the polynomial ring over a field KK, and let AA be a finitely generated standard graded SS-algebra. We show that if the defining ideal of AA has a quadratic initial ideal, then all the graded components of AA are componentwise linear. Applying this result to the Rees ring R(I)\mathcal{R}(I) of a graded ideal II gives a criterion on II to have componentwise linear powers. Moreover, for any given graph GG, a construction on GG is presented which produces graphs whose cover ideals IGI_G have componentwise linear powers. This in particular implies that for any Cohen-Macaulay Cameron-Walker graph GG all powers of IGI_G have linear resolutions. Moreover, forming a cone on special graphs like unmixed chordal graphs, path graphs and Cohen-Macaulay bipartite graphs produces cover ideals with componentwise linear powers.

Keywords

Cite

@article{arxiv.2309.01677,
  title  = {Ideals with componentwise linear powers},
  author = {Takayuki Hibi and Somayeh Moradi},
  journal= {arXiv preprint arXiv:2309.01677},
  year   = {2025}
}