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Related papers: A note on the Severi problem for toric surfaces

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Suppose $Y$ is a smooth variety equipped with a top form. We prove a simple theorem giving a sharp lower bound on the geometric genus of a family of subvarieties of $Y$, in terms of the dimension of this family. Two elementary applications…

Algebraic Geometry · Mathematics 2024-10-16 Yeuk Hay Joshua Lam , Federico Moretti , Giovanni Passeri

In this paper, we show that Severi varieties parameterizing irreducible reduced planar curves of a given degree and geometric genus are either empty or irreducible in any characteristic. Following Severi's original idea, this gives a new…

Algebraic Geometry · Mathematics 2023-01-06 Karl Christ , Xiang He , Ilya Tyomkin

For a complete, smooth toric variety Y, we describe the graded vector space T_Y^1. Furthermore, we show that smooth toric surfaces are unobstructed and that a smooth toric surface is rigid if and only if it is Fano. For a given toric…

Algebraic Geometry · Mathematics 2011-02-23 Nathan Owen Ilten

Let $\mathcal{K}$ be the space of properly embedded minimal tori in quotients of $\R^3$ by two independent translations, with any fixed (even) number of parallel ends. After an appropriate normalization, we prove that $\mathcal{K}$ is a…

Differential Geometry · Mathematics 2007-05-23 Joaquin Perez , M. Magdalena Rodriguez , Martin Traizet

We study the subvariety of singular sections, the discriminant, of a base point free linear system $|L|$ on a smooth toric variety $X$. On one hand we describe pairs $(X,L)$ for which the discriminant is of low dimension. Precisely, we…

Algebraic Geometry · Mathematics 2021-06-09 Roberto Muñoz , Álvaro Nolla

We construct a new family of minimal surfaces of general type with $p_g=q=2$ and $K^2=6$, whose Albanese map is a quadruple cover of an abelian surface with polarization of type $(1,3)$. We also show that this family provides an irreducible…

Algebraic Geometry · Mathematics 2014-12-01 Matteo Penegini , Francesco Polizzi

That short note, meant as an addendum to [CCE14], enhances the results contained in loc. cit. In particular it is proven here that a linear K{\"a}hler group is already the fundamental group of a smooth complex projective variety. This is…

Algebraic Geometry · Mathematics 2016-10-26 Benoît Claudon

This article studies the relationship between tropical Severi varieties and secondary fans. In the case when tropical Severi varieties are hypersurfaces this relationship is very well known; specifically, in this case, a tropical Severi…

Algebraic Geometry · Mathematics 2015-12-08 Jihyeon Jessie Yang

We investigate the class of degenerations of smooth cubic surfaces which are obtained from degenerating their Cox rings to toric algebras. More precisely, we work in the spirit of Sturmfels and Xu who use the theory of Khovanskii bases to…

Algebraic Geometry · Mathematics 2020-02-28 Maria Donten-Bury , Paul Görlach , Milena Wrobel

We construct 1-parameter families of non-periodic embedded minimal surfaces of infinite genus in $T \times \mathbb{R}$, where $T$ denotes a flat 2-tori. Each of our families converges to a foliation of $T \times \mathbb{R}$ by $T$. These…

Differential Geometry · Mathematics 2021-02-08 Hao Chen , Martin Traizet

We introduce the class of weakly log canonical singularities, a natural generalization of semi-log canonical singularities. Toric varieties (associated to toric face rings, possibly non-normal or reducible) which have weakly (semi-) log…

Algebraic Geometry · Mathematics 2017-11-02 Florin Ambro

We describe a class of toric varieties in the $N$-dimensional affine space which are minimally defined by no less than $N-2$ binomial equations.

Algebraic Geometry · Mathematics 2007-05-23 Margherita Barile

This note presents a formula for the enumerative invariants of arbitrary genus in toric surfaces. The formula computes the number of curves of a given genus through a collection of generic points in the surface. The answer is given in terms…

Algebraic Geometry · Mathematics 2007-05-23 Grigory Mikhalkin

The Severi and Scorza varieties are the limiting cases of a theorem of Zak conjectured by Hartshorne. Zak also classified the Severi and Scorza varieties. Surprisingly enough, there are only 4 Severi varieties, one for each dimension 2,4,8…

Algebraic Geometry · Mathematics 2007-05-23 P. E. Chaput

The geometric and algebraic properties of smooth projective varieties with 1-regular structure sheaf are well understood, and the complete classification of these varieties is a classical result. The aim of this paper is to study the next…

Algebraic Geometry · Mathematics 2018-03-06 Sijong Kwak , Jinhyung Park

For each closed orientable surface we introduce a simplical complex with some additional structure which is a version of the complex of curves of this surface adjusted to investigation of its Torelli group. We call this complex the Torelli…

Geometric Topology · Mathematics 2007-05-23 Benson Farb , Nikolai V. Ivanov

We study the topological invariant $\phi$ of Kwieci\'nski and Tworzewski, particularly beyond the case of mappings with smooth targets. We derive a lower bound for $\phi$ of a general mapping, which is similarly effective as the upper bound…

Complex Variables · Mathematics 2016-12-19 Hadi Seyedinejad

We prove the Lipman-Zariski conjecture for complex surface singularities of genus one, and also for those of genus two whose link is not a rational homology sphere. As an application, we characterize complex $2$-tori as the only normal…

Algebraic Geometry · Mathematics 2021-05-07 Patrick Graf

We give an algorithm for computing Segre classes of subschemes of arbitrary projective varieties by computing degrees of a sequence of linear projections. Based on the fact that Segre classes of projective varieties commute with…

Algebraic Geometry · Mathematics 2015-11-30 Corey Harris

The main purpose of this notes is to supplement the paper reid, which treated Minimal Model Program (also called Mori's Program) on toric varieties. We calculate lengths of negative extremal rays of toric varieties. As an application, we…

Algebraic Geometry · Mathematics 2007-05-23 Osamu Fujino
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