English

Asymptotically maximal families of hypersurfaces in toric varieties

Algebraic Geometry 2007-05-23 v1

Abstract

A real algebraic variety is maximal (with respect to the Smith-Thom inequality) if the sum of the Betti numbers (with Z2\mathbb{Z}_2 coefficients) of the real part of the variety is equal to the sum of Betti numbers of its complex part. We prove that there exist polytopes that are not Newton polytopes of any maximal hypersurface in the corresponding toric variety. On the other hand we show that for any polytope Δ\Delta there are families of hypersurfaces with the Newton polytopes (λΔ)λN(\lambda\Delta)_{\lambda \in \mathbb{N}} that are asymptotically maximal when λ\lambda tends to infinity. We also show that these results generalize to complete intersections.

Keywords

Cite

@article{arxiv.math/0504482,
  title  = {Asymptotically maximal families of hypersurfaces in toric varieties},
  author = {Benoit Bertrand},
  journal= {arXiv preprint arXiv:math/0504482},
  year   = {2007}
}

Comments

18 pages, 1 figure