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Related papers: Helly-type Theorems for Plane Convex Curves

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We apply the methods of Heegaard Floer homology to identify topological properties of complex curves in the complex projective plane. As one application, we resolve an open conjecture that constrains the Alexander polynomial of the link of…

Algebraic Geometry · Mathematics 2016-09-15 Maciej Borodzik , Charles Livingston

A theorem of Picard's type is proved for entire holomorphic mappings into complex projective varieties. This theorem has local character in the sense that the existence of Julia directions can be proved under a natural additional…

Complex Variables · Mathematics 2025-07-30 Alexandre Eremenko

Hadwiger's theorem is a Helly-type theorem involving common transversals to families of convex sets instead of common intersections. Subsequently, Pollack and Wenger identified a necessary and sufficient condition, called a consistent…

Combinatorics · Mathematics 2025-12-03 Ilani Axelrod-Freed , João Pedro Carvalho , Yuki Takahashi

In this long survey article we show that the theory of elliptic and hyperelliptic curves can be extended naturally to all superelliptic curves. We focus on automorphism groups, stratification of the moduli space $\mathcal{M}_g$, binary…

Algebraic Geometry · Mathematics 2023-11-30 Andreas Malmendier , Tony Shaska

This study introduces a new type of general helix called associated helix which is associated to a special surface curve. The basic idea is to determinate the parametric form of an associated helix by means of Darboux frame and surface…

General Mathematics · Mathematics 2022-01-25 Mehmet Önder

We describe degenerations of projective plane curves to curves containing a fixed line $l$ as a component, and show that $H^1({\overline V}_{n,d,m}, {\Cal O} (r))=0, r \in{\Bbb Z}$, where $V_{n,d,m}\subset {\Bbb P}^N (N = n(n+3)/2)$ is the…

alg-geom · Mathematics 2008-02-03 Robert Treger

We investigate the geometry of holomorphic curves and complex surfaces from the perspective of singularity theory. We show that, with a suitable choice of a complex bilinear symmetric form, the families of functions and mappings that…

Differential Geometry · Mathematics 2025-12-23 Amanda Dias Falqueto , Farid Tari

In this paper, we present a variety of problems in the interface between combinatorics and geometry around the theorems of Helly, Radon, Carath\'eodory, and Tverberg. Through these problems we describe the fascinating area of Helly-type…

Combinatorics · Mathematics 2021-10-28 Imre Bárány , Gil Kalai

Helly graphs are graphs in which every family of pairwise intersecting balls has a non-empty intersection. This is a classical and widely studied class of graphs. In this article we focus on groups acting geometrically on Helly graphs --…

Group Theory · Mathematics 2025-01-08 Jérémie Chalopin , Victor Chepoi , Anthony Genevois , Hiroshi Hirai , Damian Osajda

We prove that every polynomially convex arc is contained in a polynomially convex simple closed curve. We also establish results about polynomial hulls of arcs and curves that are locally rectifiable outside a polynomially convex subset.

Complex Variables · Mathematics 2021-06-21 Alexander J. Izzo , Edgar Lee Stout

For every simplicial complex K there exists a vertex-transitive simplicial complex homotopy equivalent to a wedge of copies of K with some copies of the circle. It follows that every simplicial complex can occur as a homotopy wedge summand…

Combinatorics · Mathematics 2014-09-18 Michal Adamaszek

We determine conditions that guarantee that a hyperelliptic or plane curve over a field of characteristic not equal to 2 can be defined over its field of moduli. We also give new examples of curves not definable over their fields of moduli.

Number Theory · Mathematics 2007-05-23 Bonnie Huggins

Given a smooth curve defined over a field $k$ that admits a non-singular plane model over $\overline{k}$, a fixed separable closure of $k$, it does not necessarily have a non-singular plane model defined over the field $k$. We determine…

Number Theory · Mathematics 2016-11-15 Eslam Badr , Francesc Bars , Elisa Lorenzo

Using an explicit family of plane quartic curves, we prove the existence of a genus 3 curve over any finite field of characteristic 3 whose number of rational points stays within a fixed distance from the Hasse-Weil-Serre upper bound. We…

Number Theory · Mathematics 2007-05-23 Roland Auer , Jaap Top

We give explicit formulas for the number of distinct elliptic curves over a finite field, up to isomorphism, in the families of Legendre, Jacobi, Hessian and generalized Hessian curves.

Algebraic Geometry · Mathematics 2011-12-30 Reza Rezaeian Farashahi

In this paper, we introduce a new class of curves \alpha called a f-rectifying curves, which its f-position vector defined by {\alpha}_{f}(s)=\int f(s)T(s)ds always lie in the rectifying plane of \alpha, where f is an integrable function…

Differential Geometry · Mathematics 2022-01-25 Fouzi Hathout

In this text we expose basic cases of some fundamental ideas and methods of topology. Namely, of homotopy, degree, fundamental group, covering, Whitehead invariant, etc. This is done by considering the elementary example: closed polygonal…

History and Overview · Mathematics 2026-05-07 E. Alkin , O. Nikitenko , A. Skopenkov

A description of the class of spectral curves, and explicit formulas for algebraic-geometric action-angle coordinates are obtained for the Hitchin systems on hyperelliptic curves, for any complex simple Lie algebra of the types $A_l$,…

Mathematical Physics · Physics 2020-05-11 O. K. Sheinman

In this paper, as a result of a theorem of Serre on congruence properties, a complete solution is given for an open question (see the text) presented recently by Kim, Koo and Park. Some further questions and results on similar types of…

Number Theory · Mathematics 2012-06-05 Derong Qiu

The existence of translated curves for quasiperiodically forced maps is established, under very mild regularity hypotheses, for rotation numbers of constant type. Among the translated curves, the invariant curves are characterized as the…

Dynamical Systems · Mathematics 2026-03-31 Amadeu Delshams , Rafael Ortega