EFFECTIVE DIVISORS ON BOTT–SAMELSON VARIETIES
نویسندگان
چکیده
منابع مشابه
Effective divisors on moduli spaces of curves and abelian varieties
The pseudo-effective cone Eff(X) of a smooth projective variety X is a fundamental, yet elusive invariant. On one hand, a few general facts are known: the interior of the effective cone is the cone of big divisors so, in particular, X is of general type if and only if KX ∈ int(Eff(X)); less obviously [4], a variety X is uniruled if and only if KX is not pseudo-effective and the dual of Eff(X) i...
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In [Bat92] Batyrev studied the cone of pseudo-effective divisors on Q-factorial terminal threefolds and its dual cone, the cone of nef curves. Given a uniruled Q-factorial terminal threefold X , and an ample divisor H on X , he showed that the effective threshold of H (see Definition 1.5 below) is a rational number. Using similar arguments, Fujita generalized this result to log terminal pairs (...
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ژورنال
عنوان ژورنال: Transformation Groups
سال: 2018
ISSN: 1083-4362,1531-586X
DOI: 10.1007/s00031-018-9493-6