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Related papers: Toric Fano varieties and birational morphisms

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The cohomological rigidity problem for toric manifolds asks whether toric manifolds are diffeomorphic (or homeomorphic) if their integral cohomology rings are isomorphic. Many affirmative partial solutions to the problem have been obtained…

Algebraic Topology · Mathematics 2020-05-29 Akihiro Higashitani , Kazuki Kurimoto , Mikiya Masuda

We study (smooth, complex) Fano 4-folds X having a rational contraction of fiber type, that is, a rational map X-->Y that factors as a sequence of flips followed by a contraction of fiber type. The existence of such a map is equivalent to…

Algebraic Geometry · Mathematics 2020-06-24 Cinzia Casagrande

We explicitly construct the smooth toric Fano variety which is isomorphic to the blow-up of the projective space at torus invariant points in codimension one by anti-flips.

Algebraic Geometry · Mathematics 2023-05-17 Hiroshi Sato , Shigehito Tsuzuki

Let (X,D) be a dlt pair, where X is a normal projective variety. Let S denote the support of the rounddown of D, and K the canonical divisor of X. We show that any smooth family of canonically polarized varieties over X\S is isotrivial if…

Algebraic Geometry · Mathematics 2019-02-20 Daniel Lohmann

We consider subtorus actions on divisorial toric varieties. Here divisoriality means that the variety has many Cartier divisors like quasiprojective and smooth ones. We characterize when a subtorus action on such a toric variety admits a…

Algebraic Geometry · Mathematics 2007-05-23 A. A'Campo-Neuen , J. Hausen

In this paper we explain the complete biregular classification of all 4-dimensional smooth toric Fano varieties. The main result states that there exist exactly 123 different types of toric Fano 4-folds up to isomorphism.

Algebraic Geometry · Mathematics 2007-05-23 Victor V. Batyrev

We obtain 866 isomorphism classes of five-dimensional nonsingular toric Fano varieties using a computer program and the database of four-dimensional reflexive polytopes. The algorithm is based on the existence of facets of Fano polytopes…

Algebraic Geometry · Mathematics 2010-02-14 Maximilian Kreuzer , Benjamin Nill

We completely classify toric weakened Fano 3-folds, that is, smooth toric weak Fano 3-folds which are not Fano but are deformed to smooth Fano 3-folds. There exist exactly 15 toric weakened Fano 3-folds up to isomorphisms.

Algebraic Geometry · Mathematics 2007-05-23 Hiroshi Sato

We study holomorphic foliations of aribitrary codimension in smooth complete toric varieties. We show that split foliations are stable if some good behaviour of their singular set is provided. As an application of these results, we exhibit…

Algebraic Geometry · Mathematics 2022-01-25 Sebastián Velazquez

We give a structure theorem for n-dimensional smooth toric Fano varieties whose associated polytope has "many" pairs of centrally symmetric vertices.

Algebraic Geometry · Mathematics 2007-05-23 Cinzia Casagrande

In this note we collect some results on the deformation theory of toric Fano varieties.

Algebraic Geometry · Mathematics 2022-06-22 Andrea Petracci

Rationality is not a constructible property in families. In this article, we consider stronger notions of rationality and study their behavior in families of Fano varieties. We first show that being toric is a constructible property in…

Algebraic Geometry · Mathematics 2025-09-29 Lena Ji , Joaquín Moraga

A conjecture of Pukhlikov states that a smooth Fano variety of dimension at least four and index one is birationally rigid. We show that a general member of the linear system given by the ample generator of the Picard group of the moduli…

Algebraic Geometry · Mathematics 2007-05-23 Ana-Maria Castravet

We prove that any affine, resp. polarized projective, spherical variety admits a flat degeneration to an affine, resp. polarized projective, toric variety. Motivated by Mirror Symmetry, we give conditions for the limit toric variety to be a…

Algebraic Geometry · Mathematics 2007-05-23 Valery Alexeev , Michel Brion

There exist exactly 166 4-dimensional reflexive polytopes such that the corresponding 4-dimensional Gorenstein toric Fano varieties have at worst terminal singularities in codimension 3 and their anticanonical divisor is divisible by 2. For…

Algebraic Geometry · Mathematics 2017-08-23 Victor Batyrev , Maximilian Kreuzer

Given $X$ a smooth projective toric variety, we construct a morphism from a closed substack of the moduli space of stable maps to $X$ to the moduli space of quasimaps to $X$. If $X$ is Fano, we show that this morphism is surjective. The…

Algebraic Geometry · Mathematics 2024-12-24 Alberto Cobos Rabano

Let $X$ be a K3 surface with Picard number 1 and genus $g$, such that $g\not\equiv 3 \mod 4$. In this paper, we show that $X$ is a Fano visitor, i.e., there is a smooth Fano variety $Y$ and an embedding $D^b(X)\hookrightarrow D^b(Y)$ given…

Algebraic Geometry · Mathematics 2025-05-08 Anibal Aravena

In this paper, we introduce the notion of toric special weak Fano manifolds, which have only special primitive crepant contractions. We study the structure of them, and in particular completely classify smooth toric special weak Fano…

Algebraic Geometry · Mathematics 2021-05-26 Hiroshi Sato

We characterize the smooth toric varieties for which the Merkurjev spectral sequence, connecting equivariant and ordinary K-theory, degenerates. We find under which conditions on the support of the fan the $E^2$ terms of the spectral…

Algebraic Geometry · Mathematics 2007-05-23 Silvano Baggio

We give a description of all log-Fano pairs (X, D) where X is a smooth toric surface and D a reduced simple normal crossing divisor such that the pair (X, D) is equivariant.

Algebraic Geometry · Mathematics 2022-04-21 Achim Napame
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