Hodge level and effective non-vanishing for smooth weighted complete intersections

Abstract

We prove that for every smooth well formed weighted complete intersection of general type of dimension $n>0$, the Hodge number $h^{0,n}(X)$ is positive; in other words, its Hodge level is maximal. We also obtain an explicit lower bound for the geometric genus $p_g(X)$. This implies that the only weighted complete intersection of general type that is not a numerical intersection with a linear cone with $p_g(X)=1$ is $X_{6,6}\subset \mathbb{P}(1,2,2,3,3)$. We also prove the Ambro--Kawamata effective non-vanishing conjecture for smooth well formed weighted complete intersections.

10 pages. Revised version with a new title. Added a proof of the Ambro--Kawamata effective non-vanishing conjecture for smooth well formed weighted complete intersections