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arXiv · 2210.00967

Strong non-vanishing of cohomologies and strong non-freeness of adjoint line bundles on $n$-Raynaud surfaces

Yongming Zhang
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Abstract

We begin by formally defining n-Tango curves and n-Raynaud surfaces. Our investigation then focuses on the pathological behaviors exhibited by n-Raynaud surfaces. As a direct corollary of this analysis, we present a concise disproof of Fujita's conjecture for surfaces in positive characteristics.

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Yongming Zhang. 2022-10-03. Strong non-vanishing of cohomologies and strong non-freeness of adjoint line bundles on $n$-Raynaud surfaces. https://arxiv.org/abs/2210.00967

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