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Related papers: Fano threefolds with affine canonical extensions

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We present a smooth, complete toric threefold with no nontrivial nef line bundles. This is a counterexample to a recent conjecture of Fujino.

Algebraic Geometry · Mathematics 2007-05-23 Sam Payne

Given a smooth non-hyperelliptic prime Fano threefold X, we prove the existence of all rank 2 ACM vector bundles on X by deformation of semistable sheaves. We show that these bundles move in generically smooth components of the…

Algebraic Geometry · Mathematics 2011-05-04 Maria Chiara Brambilla , Daniele Faenzi

In this note we prove that any toric Fano manifold with nef tangent bundle is a product of projective spaces. In particular, it implies that Campana-Peternell conjecture hold for toric manifolds.

Algebraic Geometry · Mathematics 2015-06-19 Qilin Yang

We determine the rationality of very general quasismooth Fano 3-fold weighted hypersurfaces completely and determine the stable rationality of them except for cubic 3-folds. More precisely we prove that (i) very general Fano 3-fold weighted…

Algebraic Geometry · Mathematics 2017-09-25 Takuzo Okada

A V_{12} Fano threefold is a smooth Fano threefold X of index 1 with Pic X = Z and (-K_X)^3=12. We show that the bounded derived category of coherent sheaves on any V_{12} threefold X admits a semiorthogonal decomposition consisting of two…

Algebraic Geometry · Mathematics 2007-05-23 Alexander Kuznetsov

A smooth variety is said to satisfy Condition (A) if every finite abelian subgroup of its automorphism group has a fixed point. We classify smooth Fano 3-folds that satisfy Condition (A).

Algebraic Geometry · Mathematics 2025-05-21 Hamid Abban , Ivan Cheltsov , Takashi Kishimoto , Frederic Mangolte

We describe the moduli space of rational curves on smooth Fano varieties of coindex 3. For varieties of dimension 5 or greater, we prove the moduli space has a single irreducible component for each effective numerical class of curves. For…

Algebraic Geometry · Mathematics 2024-09-04 Eric Jovinelly , Fumiya Okamura

We show that mixed-characteristic and equi-characteristic small deformations of 3-dimensional canonical (resp. terminal) singularities with perfect residue field of characteristic $p>5$ are canonical (resp. terminal). We discuss…

Algebraic Geometry · Mathematics 2024-03-08 Fabio Bernasconi , Iacopo Brivio , Stefano Filipazzi

We show that the nefness of the canonical bundle of compact K\"ahler threefolds is invariant under deformed symplectic diffeomorphisms.

Algebraic Geometry · Mathematics 2015-12-22 Hsueh-Yung Lin

We prove that the Fano variety of lines of a generic cubic fourfold containing a plane is isomorphic to a moduli space of twisted stable complexes on a K3 surface. On the other hand, we show that the Fano varieties are always birational to…

Algebraic Geometry · Mathematics 2011-12-26 Emanuele Macri , Paolo Stellari

Let X be a complex-projective contact manifold whose second Betti-number is one. It has long been conjectured that X should then be rational-homogeneous, or equivalently, that there exists an embedding of X into a projective space whose…

Algebraic Geometry · Mathematics 2007-05-23 Stefan Kebekus

We classify families of free rational curves on all smooth Fano threefolds over the complex numbers. In particular, we prove the family of very free rational curves representing any fixed numerical curve class is either irreducible or…

Algebraic Geometry · Mathematics 2024-09-04 Andrew Burke , Eric Jovinelly

We study the moduli spaces of rational curves on prime Fano threefolds of index 1. For general threefolds of most genera we compute the dimension and the number of irreducible components of these moduli spaces. Our results confirm Geometric…

Algebraic Geometry · Mathematics 2019-08-26 Brian Lehmann , Sho Tanimoto

We give necessary and sufficient conditions for unirationality and rationality of Fano threefolds of geometric Picard rank-1 over an arbitrary field of zero characteristic.

Algebraic Geometry · Mathematics 2021-04-29 Alexander Kuznetsov , Yuri Prokhorov

The purpose of this paper is to translate positivity properties of the tangent bundle (and the anti-canonical bundle) of an algebraic manifold into existence and movability properties of rational curves and to investigate the impact on the…

Algebraic Geometry · Mathematics 2016-09-06 Frédéric Campana , Thomas Peternell

We give an algebraic characterization of the possible characteristic tensors of an infinitesimally homogeneous affine manifold with G-structure.

Differential Geometry · Mathematics 2010-08-27 Carlos Alberto Marin Arango

Generalising a classical theorem by Ueno, we prove structure results for manifolds with nef or semiample cotangent bundle.

Algebraic Geometry · Mathematics 2017-11-07 Andreas Höring

This paper is devoted to the study of holomorphic distributions of dimension and codimension one on smooth weighted projective complete intersection Fano manifolds threedimensional, with Picard number equal to one. We study the relations…

Algebraic Geometry · Mathematics 2020-01-31 Alana Cavalcante , Mauricio Corrêa , Simone Marchesi

We classify smooth locally free actions of the real affine group on closed orientable three-dimensional manifolds up to smooth conjugacy. As a corollary, there exists a non-homogeneous action when the manifold is the unit tangent bundle of…

Dynamical Systems · Mathematics 2011-10-21 Masayuki Asaoka

We identify all smooth manifolds of curves for Heath-Jarrow-Morton models that are consistent with any tangential diffusion coefficient. In fact, we show that these manifolds cannot be affine but must be of linear-rational type.

Mathematical Finance · Quantitative Finance 2025-11-17 Andreas Celary , Paul Krühner