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Effective Non-vanishing for Algebraic Surfaces in Positive Characteristic

Qihong Xie
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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.

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Qihong Xie. 2006-05-23. Effective Non-vanishing for Algebraic Surfaces in Positive Characteristic. https://arxiv.org/abs/math/0509086

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