English

Smooth hypersurface sections containing a given subscheme over a finite field

Algebraic Geometry 2017-04-03 v1 Number Theory

Abstract

We use the "closed point sieve" to prove a variant of a Bertini theorem over finite fields. Specifically, given a smooth quasi-projective subscheme X of P^n of dimension m over F_q, and a closed subscheme Z in P^n such that Z intersect X is smooth of dimension l, we compute the fraction of homogeneous polynomials vanishing on Z that cut out a smooth subvariety of X. The fraction is positive if m>2l.

Keywords

Cite

@article{arxiv.1012.0628,
  title  = {Smooth hypersurface sections containing a given subscheme over a finite field},
  author = {Bjorn Poonen},
  journal= {arXiv preprint arXiv:1012.0628},
  year   = {2017}
}

Comments

7 pages. This paper appeared a few years ago. (I'm posting it in response to a request for the TeX file.)

R2 v1 2026-06-21T16:52:50.525Z