English

Determinants of incidence and Hessian matrices arising from the vector space lattice

Combinatorics 2016-09-15 v2 Commutative Algebra

Abstract

Let V=i=0nVi\mathcal{V}=\bigsqcup_{i=0}^n\mathcal{V}_i be the lattice of subspaces of the nn-dimensional vector space over the finite field Fq\mathbb{F}_q and let A\mathcal{A} be the graded Gorenstein algebra defined over Q\mathbb{Q} which has V\mathcal{V} as a Q\mathbb{Q} basis. Let FF be the Macaulay dual generator for A\mathcal{A}. We compute explicitly the Hessian determinant 2FXiXj|\frac{\partial ^2F}{\partial X_i \partial X_j}| evaluated at the point X1=X2==XN=1X_1 = X_2 = \cdots = X_N=1 and relate it to the determinant of the incidence matrix between V1\mathcal{V}_1 and Vn1\mathcal{V}_{n-1}. Our exploration is motivated by the fact that both of these matrices arise naturally in the study of the Sperner property of the lattice and the Lefschetz property for the graded Artinian Gorenstein algebra associated to it.

Keywords

Cite

@article{arxiv.1408.2136,
  title  = {Determinants of incidence and Hessian matrices arising from the vector space lattice},
  author = {Saeed Nasseh and Alexandra Seceleanu and Junzo Watanabe},
  journal= {arXiv preprint arXiv:1408.2136},
  year   = {2016}
}