English

Strong Stability of Cotangent Bundles of Cyclic Covers

Algebraic Geometry 2014-05-28 v2

Abstract

Let XX be a smooth projective variety over an algebraically closed field kk of characteristic p>0p>0 of dimX4\dim X\geq 4 and Picard number ρ(X)=1\rho(X)=1. Suppose that XX satisfies Hi(X,FXm(\OmgXj)\Ls1)=0H^i(X,F^{m*}_X(\Omg^j_X)\otimes\Ls^{-1})=0 for any ample line bundle \Ls\Ls on XX, and any nonnegative integers m,i,jm,i,j with 0i+j<dimX0\leq i+j<\dim X, where FX:XXF_X:X\rightarrow X is the absolute Frobenius morphism. We prove that by procedures combining taking smooth hypersurfaces of dimension 3\geq 3 and cyclic covers along smooth divisors, if the resulting smooth projective variety YY has ample (resp. nef) canonical bundle ωY\omega_Y, then \OmgY\Omg_Y is strongly stable ((resp. strongly semistable)) with respect to any polarization.

Keywords

Cite

@article{arxiv.1405.0106,
  title  = {Strong Stability of Cotangent Bundles of Cyclic Covers},
  author = {Lingguang Li and Junchao Shentu},
  journal= {arXiv preprint arXiv:1405.0106},
  year   = {2014}
}

Comments

To appear in Comptes Rendus Math\'ematique