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arXiv · 1003.1782

Big arithmetic divisors on the projective spaces over Z

Atsushi Moriwaki
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Abstract

This paper is an enhancement of the previous note "Explicit computations of Zariski decompositions on P_Z^1". In this paper, we observe several properties of a certain kind of an arithmetic divisor D on the n-dimensional projective space over Z and give the exact form of the Zariski decomposition of D on the projective line over Z. Further, we show that, if n>=2 and D is big and non-nef, then, for any birational morphism f: X --> P^n_Z of projective, generically smooth and normal arithmetic varieties, we can not expect a suitable Zariski decomposition of f^*(D). We also give a concrete construction of Fujita's approximation of D.

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Atsushi Moriwaki. 2010-03-09. Big arithmetic divisors on the projective spaces over Z. https://doi.org/10.1215/21562261-1299882

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