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Related papers: Non-existence of torically maximal hypersurfaces

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We show that the normal points of a cubic hypersurface in projective space have canonical singularities unless the hypersurface is an iterated cone over an elliptic curve. As an application, we give a simple linear algebraic description of…

Algebraic Geometry · Mathematics 2026-02-12 Ashima Bansal , Supravat Sarkar , Shivam Vats

We study area-stationary, or maximal, surfaces in the space ${\mathbb L}({\mathbb H}^3)$ of oriented geodesics of hyperbolic 3-space, endowed with the canonical neutral K\"ahler structure. We prove that every holomorphic curve in ${\mathbb…

Differential Geometry · Mathematics 2010-02-10 Nikos Georgiou

We relate the geometry of curves to the notion of hyperbolicity in real algebraic geometry. A hyperbolic variety is a real algebraic variety that (in particular) admits a real fibered morphism to a projective space whose dimension is equal…

Algebraic Geometry · Mathematics 2022-10-04 Mario Kummer , Rainer Sinn

We first show that the union of a projective curve with one of its extremal secant lines satisfies the linear general position principle for hyperplane sections. We use this to give an improved approximation of the Betti numbers of curves…

Algebraic Geometry · Mathematics 2009-05-29 Markus Brodmann , Peter Schenzel

We address the problem of the maximal finite number of real points of a real algebraic curve (of a given degree and, sometimes, genus) in the projective plane. We improve the known upper and lower bounds and construct close to optimal…

Algebraic Geometry · Mathematics 2019-09-13 Erwan Brugallé , Alex Degtyarev , Ilia Itenberg , Frédéric Mangolte

We study the geometry of stable maximal hypersurfaces in a variety of spacetimes satisfying various physically relevant curvature assumptions, for instance the Timelike Convergence Condition (TCC). We characterize stability when the target…

Differential Geometry · Mathematics 2019-03-05 Giulio Colombo , José A. S. Pelegrín , Marco Rigoli

Let $C$ be a complex irreducible plane curve that is not the vanishing locus of a modular polynomial. We show that $C$ contains finitely many real algebraic curves whose projection on each coordinate axis is a union of special geodesics.

Number Theory · Mathematics 2026-03-31 Matteo Tamiozzo

The aim of this paper is to provide a direct link between maximizing curves that occur in the construction of smooth algebraic surfaces having the maximal possible Picard numbers and reduced free plane curves with simple singularities. We…

Algebraic Geometry · Mathematics 2024-11-12 Alexandru Dimca , Piotr Pokora

We prove that maximal real algebraic curves associated with sub-Gaussian random real holomorphic sections of a smoothly curved ample line bundle are exponentially rare. This generalizes the result of Gayet and Welschinger \cite{GW} proved…

Algebraic Geometry · Mathematics 2025-04-30 Turgay Bayraktar , Emel Karaca

A Lie hypersurface in the complex hyperbolic space is a homogeneous real hypersurface without focal submanifolds. The set of all Lie hypersurfaces in the complex hyperbolic space is bijective to a closed interval, which gives a deformation…

Differential Geometry · Mathematics 2009-08-25 Tatsuyoshi Hamada , Yuji Hoshikawa , Hiroshi Tamaru

Given a real algebraic curve, embedded in projective space, we study the computational problem of deciding whether there exists a hyperplane meeting the curve in real points only. More generally, given any divisor on such a curve, we may…

Algebraic Geometry · Mathematics 2021-06-29 Huu Phuoc Le , Dimitri Manevich , Daniel Plaumann

Given a real algebraic curve in the projective 3-space, its hyperbolicity locus is the set of lines with respect to which the curve is hyperbolic. We give an example of a smooth irreducible curve whose hyperbolicity locus is disconnected…

Algebraic Geometry · Mathematics 2024-12-04 Stepan Orevkov

A polygonal surface in the pseudo-hyperbolic space H^(2,n) is a complete maximal surface bounded by a lightlike polygon in the Einstein universe Ein^(1,n) with finitely many vertices. In this article, we give several characterizations of…

Differential Geometry · Mathematics 2026-05-05 Alex Moriani

We classify complete orientable hypersurfaces of constant isotropic curvature in space forms. We show that such a hypersurface has constant mean curvature only if it is an isoparametric hypersurface, and that it is minimal if and only if it…

Differential Geometry · Mathematics 2022-10-18 H. A. Gururaja , Niteesh Kumar

We study various classes of real hypersurfaces that are not embeddable into more special hypersurfaces in higher dimension, such as spheres, real algebraic compact strongly pseudoconvex hypersurfaces or compact pseudoconvex hypersurfaces of…

Complex Variables · Mathematics 2015-02-16 Xiaojun Huang , Dmitri Zaitsev

We introduce the separating semigroup of a real algebraic curve of dividing type. The elements of this semigroup record the possible degrees of the covering maps obtained by restricting separating morphisms to the real part of the curve. We…

Algebraic Geometry · Mathematics 2020-08-04 Mario Kummer , Kristin Shaw

We study projective surfaces in $\mathbb{P}^3$ which can be written as Hadamard product of two curves. We show that quadratic surfaces which are Hadamard product of two lines are smooth and tangent to all coordinate planes, and such…

Algebraic Geometry · Mathematics 2026-03-30 Dario Antolini , Edoardo Ballico , Alessandro Oneto

We study constant mean curvature spacelike hypersurfaces and in particular maximal hypersurfaces immersed in pp-wave spacetimes satisfying the timelike convergence condition. We prove the non-existence of compact spacelike hypersurfaces…

Differential Geometry · Mathematics 2016-04-29 José A. S. Pelegrín , Alfonso Romero , Rafael M. Rubio

We study real trigonal curves and elliptic surfaces of type $\I$ (over a base of an arbitrary genus) and their fiberwise equivariant deformations. The principal tool is a real version of Grothendieck's \emph{dessins d'enfants}. We give a…

Algebraic Geometry · Mathematics 2014-06-06 Alex Degtyarev , Ilia Itenberg , Victor Zvonilov

Based on the fact that projective monomial curves in the plane are complete intersections, we give an effective inductive method for creating infinitely many monomial curves in the projective $n$-space that are set theoretic complete…

Commutative Algebra · Mathematics 2015-12-09 Tran Hoai Ngoc Nhan , Mesut Şahin