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arXiv · 1304.6686

Birational positivity in dimension 4 (with an appendix by Frédéric Campana)

Behrouz Taji
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Abstract

In this paper we prove that for a nonsingular projective variety of dimension at most 4 and with non-negative Kodaira dimension, the Kodaira dimension of coherent subsheaves of $Ω^p$ is bounded from above by the Kodaira dimension of the variety. This implies the finiteness of the fundamental group for such an $X$ provided that $X$ has vanishing Kodaira dimension and non-trivial holomorphic Euler characteristic.

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Behrouz Taji. 2013-04-24. Birational positivity in dimension 4 (with an appendix by Frédéric Campana). https://arxiv.org/abs/1304.6686

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