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arXiv · 2308.14268

The minimal volume of surfaces of log general type with non-empty non-klt locus

Jihao Liu·Wenfei Liu
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Abstract

We show that the minimal volume of surfaces of log general type, with non-empty non-klt locus on the ample model, is $\frac{1}{825}$. Furthermore, the ample model $V$ achieving the minimal volume is determined uniquely up to isomorphism. The canonical embedding presents $V$ as a degree $86$ hypersurface of $\mathbb P(6,11,25,43)$. This motivates a one-parameter deformation of $V$ to klt stable surfaces within the weighted projective space. Consequently, we identify a $\textit{complete}$ rational curve in the corresponding moduli space $M_{\frac{1}{825}}$. As an important application, we deduce that the smallest accumulation point of the set of volumes for projective log canonical surfaces equals $\frac{1}{825}$.

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Jihao Liu, Wenfei Liu. 2023-08-28. The minimal volume of surfaces of log general type with non-empty non-klt locus. https://arxiv.org/abs/2308.14268

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