Minimal 3-folds of small slope and the Noether inequality for canonically polarized 3-folds
نویسندگان
چکیده
منابع مشابه
The Noether Inequality for Smooth Minimal 3-folds
Let X be a smooth projective minimal 3-fold of general type. We prove the sharp inequality K X ≥ 2 3 (2pg(X)− 5), an analogue of the classical Noether inequality for algebraic surfaces of general type.
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Assume that X is a smooth projective 3-fold with ample KX . We study a problem of Miles Reid to prove the inequality K X ≥ 2 3 (2pg(X)− 5), where pg(X) is the geometric genus. This inequality is sharp according to known examples of M. Kobayashi. We also birationally classify arbitrary minimal 3-folds of general type with small slope.
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If X is a smooth complex projective 3-fold with ample canonical divisor K, then the inequality K ≥ 2 3 (2pg − 7) holds, where pg denotes the geometric genus. This inequality is nearly sharp. We also give similar, but more complicated, inequalities for general minimal 3-folds of general type. Introduction Given a minimal surface S of general type, we have two famous inequalities, which play cruc...
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The number h(L) of linearly independent section of a line bundle L can be used to define subschemes of JacC, called the Brill–Noether locuses. These have been studied since the 19th century, since they reflect properties of an individual curve that are beyond the control of the Riemann–Roch theorem. In this article, we recall this theory briefly in §2, then generalize it to the moduli spaces MC...
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ژورنال
عنوان ژورنال: Mathematical Research Letters
سال: 2004
ISSN: 1073-2780,1945-001X
DOI: 10.4310/mrl.2004.v11.n6.a9