English
Related papers

Related papers: Rational curves on hypersurfaces

200 papers

We lay the foundations of convex hypersurface theory in contact topology, extending the work of Giroux in dimension three. Specifically, we prove that any closed hypersurface in a contact manifold can be $C^0$-approximated by a convex one.…

Symplectic Geometry · Mathematics 2026-04-30 Joseph Breen , Austin Christian , Ko Honda , Yang Huang

Let $k$ be a non-archimedean complete valued field and let X be a smooth Berkovich analytic $k$-curve. Let $F$ be a finite locally constant \'{e}tale sheaf on $k$ whose torsion is prime to the residue characteristic. We denote by $|X|$ the…

Algebraic Geometry · Mathematics 2007-05-23 Antoine Ducros

In the present article we work out a relative setup of generic structures on surface singularities. We fix an analytic type on a subgraph of a rational homology sphere resolution graph $\mathcal{T}$ and we choose a relatively generic normal…

Algebraic Geometry · Mathematics 2021-12-30 János Nagy

We prove the existence of rotational hypersurfaces in $\mathbb{H}^n\times \mathbb{R}$ with $H_{r+1}=0$ and we classify them. Then we prove some uniqueness theorems for $r$-minimal hypersurfaces with a given (finite or asymptotic) boundary.…

Differential Geometry · Mathematics 2015-08-13 Maria Fernanda Elbert , Barbara Nelli , Walcy Santos

Using ideas from the theory of tropical curves and degeneration, we prove that any Fano hypersurface (and more generally Fano complete intersections) is swept by at most quadratic rational curves.

Algebraic Geometry · Mathematics 2011-08-23 Takeo Nishinou

We consider holomorphic mappings $H$ between a smooth real hypersurface $M\subset \bC^{n+1}$ and another $M'\subset \bC^{N+1}$ with $N\geq n$. We provide conditions guaranteeing that $H$ is transversal to $M'$ along all of $M$. In the…

Complex Variables · Mathematics 2020-06-15 Peter Ebenfelt , Duong Ngoc Son

Kontsevich and Manin gave a formula for the number $N_e$ of rational plane curves of degree $e$ through $3e-1$ points in general position in the plane. When these $3e-1$ points have coordinates in the rational numbers, the corresponding set…

Algebraic Geometry · Mathematics 2020-05-01 David Holmes , Nick Rome

Inspired by their results on the Chow rings of projective K3 surfaces, Beauville and Voisin made the following conjecture: given a projective hyperkaehler manifold, for any algebraic cycle which is a polynomial with rational coefficients of…

Algebraic Geometry · Mathematics 2014-04-09 Lie Fu

In this paper we study birational immersions from a very general smooth plane curve to a non-rational surface with $p_g=q=0$ to treat dominant rational maps from a very general surface $X$ of degree$\geq 5$ in ${\mathbb P}^3$ to smooth…

Algebraic Geometry · Mathematics 2015-03-26 Yongnam Lee , Gian Pietro Pirola

Using the path lattice cohomology we provide a conceptual topological characterization of the geometric genus for certain complex normal surface singularities with rational homology sphere links, which is uniformly valid for all…

Algebraic Geometry · Mathematics 2016-03-27 András Némethi , Baldur Sigurðsson

By considering mirror symmetry applied to conformal field theories corresponding to strings propagating in quintic hypersurfaces in projective 4-space, Candelas, de la Ossa, Green and Parkes calculated the ``number of rational curves on the…

High Energy Physics - Theory · Physics 2008-02-03 Sheldon Katz

In this note, we establish the following Second Main Theorem type estimate for every entire non-algebraically degenerate holomorphic curve $f\colon\mathbb{C}\rightarrow\mathbb{P}^n(\mathbb{C})$, in present of a {\sl generic} hypersuface…

Algebraic Geometry · Mathematics 2017-11-28 Dinh Tuan Huynh , Duc-Viet Vu , Song-Yan Xie

Under natural hypotheses we give an upper bound on the dimension of families of singular curves with hyperelliptic normalizations on a surface S with p_g(S) >0 via the study of the associated families of rational curves in Hilb^2(S). We use…

Algebraic Geometry · Mathematics 2007-05-25 Flaminio Flamini , Andreas Leopold Knutsen , Gianluca Pacienza , Edoardo Sernesi

Let W be a projective variety of dimension n+1, L a free line bundle on W, X in $H^0(L^d)$ a hypersurface of degree d which is generic among those given by sums of monomials from $L$, and let $f : Y \to X$ be a generically finite map from a…

Algebraic Geometry · Mathematics 2007-05-23 L. Chiantini , A. F. Lopez , Z. Ran

In this work we use arithmetic, geometric, and combinatorial techniques to compute the cohomology of Weil divisors of a special class of normal surfaces, the so-called rational ruled toric surfaces. These computations are used to study the…

Algebraic Geometry · Mathematics 2018-03-14 Enrique Artal Bartolo , José Ignacio Cogolludo-Agustín , Jorge Martín-Morales

Here we investigate the canonical Gaussian map for higher multiple coverings of curves, the case of double coverings being completely understood thanks to previous work by Duflot. In particular, we prove that every smooth curve can be…

Algebraic Geometry · Mathematics 2007-05-23 Edoardo Ballico , Claudio Fontanari

A very general hypersurface of dimension $n$ and degree $d$ in complex projective space is rational if $d \leq 2$, but is expected to be irrational for all $n, d \geq 3$. Hypersurfaces in weighted projective space with degree small relative…

Algebraic Geometry · Mathematics 2024-11-20 Louis Esser

We compute some numerical invariants of the lines on hyperplane sections of a smooth cubic threefold over complex numbers. We also prove that for any smooth hypersurface $X\subset \mathbb P^{n+1}$ of degree $d$ over an algebraically closed…

Algebraic Geometry · Mathematics 2020-07-08 Yiran Cheng

Let X be a smooth quasi-projective variety over the algebraic closure of the rational number field. We show that the cycle map of the higher Chow group to Deligne cohomology is injective and the higher Hodge cycles are generated by the…

Algebraic Geometry · Mathematics 2008-05-19 Morihiko Saito

We give necessary and sufficient topological conditions for a simple closed curve on a real rational surface to be approximable by smooth rational curves. We also study approximation by smooth rational curves with given complex…

Algebraic Geometry · Mathematics 2025-05-26 János Kollár , Frédéric Mangolte