Kodaira dimension

In mathematics, the pluricanonical ring of an algebraic variety V (which is non-singular), or of a complex manifold, is the graded ring  of sections of powers of the canonical bundle K. Its nth graded component (for ) is:that is, the space of sections of the n-th tensor product Kn of the canonical bundle K.The 0th graded component is sections of the trivial bundle, and is canonically the ring of regular functions; thus R is an algebra over the regular functions on V.
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