English
Related papers

Related papers: Fano manifolds whose Chern characters satisfy some…

200 papers

We find new lower bounds on the torsion orders of very general Fano hypersurfaces over (uncountable) fields of arbitrary characteristic. Our results imply that unirational parametrizations of most Fano hypersurfaces need to have enormously…

Algebraic Geometry · Mathematics 2021-03-03 Stefan Schreieder

We prove that compact complex manifolds with admitting metrics with negative Chern curvature operator either admit a $dd^c$-exact positive (1,1) current, or are K\"ahler with ample canonical bundle. In the case of complex surfaces we obtain…

Differential Geometry · Mathematics 2019-04-01 Man-Chun Lee , Jeffrey Streets

Fano varieties are subvarieties of the Grassmannian whose points parametrize linear subspaces contained in a given projective variety. These expository notes give an account of results on Fano varieties of complete intersections, with a…

Algebraic Geometry · Mathematics 2012-12-05 Paul Larsen

This paper aims to develop a theory of projective and affine structures on higher-dimensional varieties in positive characteristic. This theory deals with Frobenius-projective and Frobenius-affine structures, which have been previously…

Algebraic Geometry · Mathematics 2026-05-19 Yasuhiro Wakabayashi

We study three-dimensional Fano varieties with $\mathbb{C}^*$-action. Complementing recent results [13], we give classification results in the canonical case, where the maximal orbit quotient is $\mathbb{P}_2$ having a line arrangement of…

Algebraic Geometry · Mathematics 2019-12-18 Christoff Hische , Milena Wrobel

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 prove that the lengths of extremal rays of log canonical Fano surfaces with Picard number one satisfy the ascending chain condition. This confirms the 2-dimensional case of a conjecture stated by Fujino and Ishitsuka

Algebraic Geometry · Mathematics 2014-10-27 Evgeny Mayanskiy

We overview some recent results on Fano varieties giving evidence of their rigid nature under small deformations.

Algebraic Geometry · Mathematics 2009-11-04 Tommaso de Fernex , Christopher Hacon

We investigate power series satisfying the exponential concentration property, and show that suitable modifications of hypergeometric series respect this property. As a geometric application, we prove that the quantum period of a Fano…

Algebraic Geometry · Mathematics 2026-05-18 Jingwei Lu , Hua-Zhong Ke , Jianxun Hu

In this note we prove that any closed graph manifold admitting a metric of non-positive sectional curvature (NPC-metric) has a finite cover, which is fibered over the circle. An explicit criterion to have a finite cover, which is fibered…

Geometric Topology · Mathematics 2016-09-07 P. Svetlov

As a generalization of the Mukai conjecture, we conjecture that the Fano manifolds $X$ which satisfy the property $\rho_X(r_X-1)\geq\dim X-1$ have very special structure, where $\rho_X$ is the Picard number of $X$ and $r_X$ is the index of…

Algebraic Geometry · Mathematics 2015-04-03 Kento Fujita

We prove the $W\mathcal{O}$-rationality of klt threefolds and the rational chain connectedness of klt Fano threefolds over a perfect field of characteristic $p>5$. As a consequence, any klt Fano threefold over a finite field has a rational…

Algebraic Geometry · Mathematics 2016-12-01 Yoshinori Gongyo , Yusuke Nakamura , Hiromu Tanaka

We construct first examples of Fano varieties with torsion in their third cohomology group. The examples are constructed as double covers of linear sections of rank loci of symmetric matrices, and can be seen as higher-dimensional analogues…

Algebraic Geometry · Mathematics 2023-11-17 John Christian Ottem , Jørgen Vold Rennemo

Let $X$ be a smooth Fano manifold equipped with a `` nice '' $n$-blocks collection in the sense of \cite{cm2} and $\mathcal {F}$ a coherent sheaf on $X$. Assume that $X$ is Fano and that all blocks are coherent sheaves. Here we prove that…

Algebraic Geometry · Mathematics 2007-10-23 E. Ballico , F. Malaspina

We obtain a sufficient condition for a Fano threefold with terminal singularities to have a conic bundle structure.

Algebraic Geometry · Mathematics 2022-02-02 Yuri Prokhorov

This work deals with the study of embeddings of toric Calabi-Yau fourfolds which are complex cones over the smooth Fano threefolds. In particular, we focus on finding various embeddings of Fano threefolds inside other Fano threefolds and…

High Energy Physics - Theory · Physics 2016-11-23 Siddharth Dwivedi

In this note we consider the problem of determining which Fano manifolds can be realised as fibres of a Mori fibre space. In particular, we study the case of toric varieties, Fano manifolds with high index and some Fano manifolds with high…

Algebraic Geometry · Mathematics 2022-11-08 Giulio Codogni , Andrea Fanelli , Roberto Svaldi , Luca Tasin

We classify three-dimensional Fano varieties with canonical Gorenstein singularities of degree bigger than 64.

Algebraic Geometry · Mathematics 2015-05-13 Ilya Karzhemanov

Let X be a smooth complex Fano 4-fold. We show that if X has a small elementary contraction, then the Picard number rho(X) of X is at most 12. This result is based on a careful study of the geometry of X, on which we give a lot of…

Algebraic Geometry · Mathematics 2022-05-20 C. Casagrande

We study Fano varieties endowed with a faithful action of a symmetric group, as well as analogous results for Calabi--Yau varieties, and log terminal singularities. We show the existence of a constant $m(n)$, so that every symmetric group…

Algebraic Geometry · Mathematics 2025-02-05 Louis Esser , Lena Ji , Joaquín Moraga