Algebra & Number Theory

Effectiveness of the log Iitaka fibration for 3-folds and 4-folds

Gueorgui Todorov and Chenyang Xu

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We prove the effectiveness of the log Iitaka fibration in Kodaira codimension two for varieties of dimension 4. In particular, we finish the proof of effective log Iitaka fibration in dimension two. Also, we show that for the log Iitaka fibration, if the fiber is of dimension two, the denominator of the moduli part is bounded.

Article information

Algebra Number Theory, Volume 3, Number 6 (2009), 697-710.

Received: 20 January 2009
Revised: 9 July 2009
Accepted: 17 August 2009
First available in Project Euclid: 20 December 2017

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 14E05: Rational and birational maps
Secondary: 14J35: $4$-folds 14J30: $3$-folds [See also 32Q25]

Iitaka fibration boundedness


Todorov, Gueorgui; Xu, Chenyang. Effectiveness of the log Iitaka fibration for 3-folds and 4-folds. Algebra Number Theory 3 (2009), no. 6, 697--710. doi:10.2140/ant.2009.3.697.

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