English

Projective normality and basepoint-freeness thresholds of general polarized abelian varieties

Algebraic Geometry 2022-04-22 v1

Abstract

For a polarized abelian variety (X,L)(X,L), Z. Jiang and G. Pareschi introduce an invariant β(X,L)\beta(X,L), called the basepoint-freeness threshold. Using this invariant, we show that a general polarized abelian variety (X,L)(X,L) of dimension gg is projectively normal if χ(L)22g1\chi(L) \geq 2^{2g-1} and the type of LL is not (2,4,,4)(2,4,\dots,4). This bound is sharp since it is known that any polarized abelian variety of type (2,4,,4)(2,4,\dots,4) is not projectively normal. We also give an application of β(X,L)\beta(X,L) to the Infinitesimal Torelli Theorem for YLY \in |L|.

Keywords

Cite

@article{arxiv.2204.10035,
  title  = {Projective normality and basepoint-freeness thresholds of general polarized abelian varieties},
  author = {Atsushi Ito},
  journal= {arXiv preprint arXiv:2204.10035},
  year   = {2022}
}

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18 pages