Abstract
For every smooth complex projective variety \(W\) of dimension \(d\) and nonnegative Kodaira dimension, we show the existence of a universal constant \(m\) depending only on \(d\) and two natural invariants of the very general fibres of an Iitaka fibration of \(W\) such that the pluricanonical system \(|mK_{W}|\) defines an Iitaka fibration. This is a consequence of a more general result on polarized adjoint divisors. In order to prove these results we develop a generalized theory of pairs, singularities, log canonical thresholds, adjunction, etc.
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Birkar, C., Zhang, DQ. Effectivity of Iitaka fibrations and pluricanonical systems of polarized pairs. Publ.math.IHES 123, 283–331 (2016). https://doi.org/10.1007/s10240-016-0080-x
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DOI: https://doi.org/10.1007/s10240-016-0080-x