English

On Lyubeznik numbers of projective schemes

Commutative Algebra 2007-09-07 v1 Algebraic Geometry

Abstract

Let XX be an arbitrary projective scheme over a field kk. Let AA be the local ring at the vertex of the affine cone for some embedding ι:XPkn\iota: X\hookrightarrow \mathbb{P}^n_k. G. Lyubeznik asked (in \cite{l2}) whether the integers λi,j(A)\lambda_{i,j}(A) (defined in \cite{l1}), called the Lyubeznik numbers of AA, depend only on XX, but not on the embedding. In this paper, we make a big step toward a positive answer to this question by proving that in positive characteristic, for a fixed XX, the Lyubezink numbers λi,j(A)\lambda_{i,j}(A) of the local ring AA, can only achieve finitely many possible values under all choices of embeddings.

Keywords

Cite

@article{arxiv.0709.0747,
  title  = {On Lyubeznik numbers of projective schemes},
  author = {Wenliang Zhang},
  journal= {arXiv preprint arXiv:0709.0747},
  year   = {2007}
}
R2 v1 2026-06-21T09:14:22.863Z