English

Linear resolution of products of monomial ideals related to maximal minors

Commutative Algebra 2026-03-02 v3

Abstract

Let X X be an m×n m \times n matrix of distinct indeterminates over a field K K , where mn m \le n . Set the polynomial ring K[X]:=K[Xij:1im,1jn] K[X] := K[X_{ij} : 1 \le i \le m, 1 \le j \le n] . Let 1k<ln 1 \le k < l \le n be such that lk+1m l - k + 1 \ge m . Consider the submatrix Ykl Y_{kl} of consecutive columns of X X from k k th column to l l th column. Let Jkl J_{kl} be the ideal generated by `diagonal monomials' of all m×m m \times m submatrices of Ykl Y_{kl} , where the diagonal monomial of a square matrix means product of its main diagonal entries. We show that Jk1l1Jk2l2Jksls J_{k_1 l_1} J_{k_2 l_2} \cdots J_{k_s l_s} has a linear free resolution, where k1k2ks k_1 \le k_2 \le \cdots \le k_s and l1l2ls l_1 \le l_2 \le \cdots \le l_s . This result is a variation of a theorem due to Bruns and Conca. Moreover, our proof is self-contained, elementary and combinatorial.

Keywords

Cite

@article{arxiv.1902.09748,
  title  = {Linear resolution of products of monomial ideals related to maximal minors},
  author = {Arindam Banerjee and Dipankar Ghosh and S. Selvaraja},
  journal= {arXiv preprint arXiv:1902.09748},
  year   = {2026}
}

Comments

10 pages, Revised version, with modifications to the title and the introduction. To appear in J. Ramanujan Math. Soc