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Viewing Version 5 of 'Kodaira dimension'
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Title of object: Kodaira dimension
Canonical Name: KodairaDimension
Type: Definition

Created on: 2006-09-01 15:08:51
Modified on: 2006-11-15 10:19:22

Creator: Mravinci
Modifier: Mravinci
Author: yark
Author: Lando47
Author: PrimeFan

Classification: msc:14E05

Revision comment (for changes between this and next version):

Hmm, another instance of copying from Wikipedia, perhaps?

Preamble:

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Content:

This entry makes no sense, and the owner has rejected a correction requesting that it be fixed.

Named after the Japanese mathematician Kunihiko Kodaira, the {\em Kodaira dimension} $K$ of a non-singular algebraic variety $V$ is $t - 1$, where $t$ is the transcendence degree of a graded ring $R$.

If $V$ is on the projective line and $R$ is in the zero ring, the Kodaira dimension is set as $−1$. But the Kodaira dimension is 0 if the curve $K$ is both elliptic and a trivial bundle, and all plurigenera are 1.