On Algebraic Varieties with Finite Polyhedral Mori Cone
نویسندگان
چکیده
The fundamental property of Fano varieties with mild singularities is that they have a finite polyhedral Mori cone. Thus, it is very interesting to ask: What we can say about algebraic varieties with a finite polyhedral Mori cone? I give a review of known results. All of them were obtained applying methods which were originated in the theory of discrete groups generated by reflections in hyperbolic spaces with a fundamental chamber of finite volume.
منابع مشابه
A Remark on Algebraic Surfaces with Polyhedral Mori Cone
We denote by FPMC the class of all non-singular projective algebraic surfaces X over C with finite polyhedral Mori cone NE(X) ⊂ NS(X)⊗ R. If ρ(X) = rk NS(X) ≥ 3, then the set Exc(X) of all exceptional curves on X ∈ FPMC is finite and generates NE(X). Let δE(X) be the maximum of (−C ) and pE(X) the maximum of pa(C) respectively for all C ∈ Exc(X). For fixed ρ ≥ 3, δE and pE we denote by FPMCρ,δE...
متن کاملPolyhedral Divisors and Algebraic Torus Actions
We provide a complete description of normal affine varieties with effective algebraic torus action in terms of what we call proper polyhedral divisors on semiprojective varieties. Our theory extends classical cone constructions of Dolgachev, Demazure and Pinkham to the multigraded case, and it comprises the theory of affine toric varieties.
متن کاملThe cone conjecture for Calabi-Yau pairs in dimension two
A central idea of minimal model theory as formulated by Mori is to study algebraic varieties using convex geometry. The cone of curves of a projective variety is defined as the convex cone spanned by the numerical equivalence classes of algebraic curves; the dual cone is the cone of nef line bundles. For Fano varieties (varieties with ample anticanonical bundle), these cones are rational polyhe...
متن کاملAlgebraic surfaces and hyperbolic geometry
Many properties of a projective algebraic variety can be encoded by convex cones, such as the ample cone and the cone of curves. This is especially useful when these cones have only finitely many edges, as happens for Fano varieties. For a broader class of varieties which includes Calabi-Yau varieties and many rationally connected varieties, the Kawamata-Morrison cone conjecture predicts the st...
متن کاملAsymptotic cohomological functions of toric divisors
We study functions on the class group of a toric variety measuring the rates of growth of the cohomology groups of multiples of divisors. We show that these functions are piecewise polynomial with respect to finite polyhedral chamber decompositions. As applications, we express the self-intersection number of a T -Cartier divisor as a linear combination of the volumes of the bounded regions in t...
متن کامل