Effective Non-vanishing for Algebraic Surfaces in Positive Characteristic
arXiv:math/0509086
Abstract
We give a theorem on the effective non-vanishing problem for algebraic surfaces in positive characteristic. For the Kawamata-Viehweg vanishing, the logarithmic Kollar vanishing and the logarithmic semipositivity, we give their counterexamples on ruled surfaces in positive characteristic.
17 pages