English

On a generalization of the Mukai conjecture for Fano fourfolds

Algebraic Geometry 2013-10-01 v2

Abstract

Let X be a complex Fano manifold of dimension n. Let s(X) be the sum of l(R)-1 for all the extremal rays of X, the edges of the cone NE(X) of curves of X, where l(R) denotes the minimum of (-K_X \cdot C) for all rational curves C whose class [C] belongs to R. We show that s(X)\leq n if n\leq 4. And for n\leq 4, we completely classify the case the equality holds. This is a refinement of the Mukai conjecture on Fano fourfolds.

Keywords

Cite

@article{arxiv.1206.1990,
  title  = {On a generalization of the Mukai conjecture for Fano fourfolds},
  author = {Kento Fujita},
  journal= {arXiv preprint arXiv:1206.1990},
  year   = {2013}
}

Comments

16 pages. v2: title changed, add references