English

Stability of tangent bundles of complete intersections and effective restriction

Algebraic Geometry 2018-10-23 v3

Abstract

For n3n\geq 3, let MM be an (n+r)(n+r)-dimensional irreducible Hermitian symmetric space of compact type and let OM(1)\mathcal{O}_M(1) be the ample generator of Pic(M)Pic(M). Let Y=H1HrY=H_1\cap\dots\cap H_r be a smooth complete intersection of dimension nn where HiOM(di)H_i\in\vert \mathcal{O}_M(d_i)\vert with di2d_i\geq 2. We prove a vanishing theorem for twisted holomorphic forms on YY. As an application, we show that the tangent bundle TYT_Y of YY is stable. Moreover, if XX is a smooth hypersurface of degree dd in YY such that the restriction Pic(Y)Pic(X)Pic(Y)\rightarrow Pic(X) is surjective, we establish some effective results for dd to guarantee the stability of the restriction TYXT_Y\vert_X. In particular, if YY is a general hypersurface in Pn+1\mathbb{P}^{n+1} and XX is general smooth divisor in YY, we show that TYXT_Y\vert_X is stable except for some well-known examples. We also address the cases where the Picard group increases by restriction.

Keywords

Cite

@article{arxiv.1711.03413,
  title  = {Stability of tangent bundles of complete intersections and effective restriction},
  author = {Jie Liu},
  journal= {arXiv preprint arXiv:1711.03413},
  year   = {2018}
}

Comments

The paper is significantly rewritten. More results on complete intersections in Hermitian symmetric spaces are included. Any comments are welcome