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arXiv · 2506.17956

Fujita-Zariski decompositions on some product threefolds

Mihai Fulger·Victor Lozovanu
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Abstract

We use explicit blow-ups and computations of birational Fujita-Zariski decompositions to determine generic infinitesimal Newton-Okounkov bodies for box-product ample polarizations on three classes of spaces: product between a curve and the projective plane, products of three curves, and the product between a curve and a Jacobian surface. In particular we compute the volume of many big but non-nef divisors on blow-ups of these threefolds.

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Mihai Fulger, Victor Lozovanu. 2025-06-22. Fujita-Zariski decompositions on some product threefolds. https://arxiv.org/abs/2506.17956

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