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Related papers: On the connectivity of some complete intersections

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We present an explicit connected spanning structure that appears in a random graph just above the connectivity threshold with high probability.

Combinatorics · Mathematics 2021-11-29 Yahav Alon , Michael Krivelevich , Peleg Michaeli

Recent work showing the existence of conflict-free almost-perfect hypergraph matchings has found many applications. We show that, assuming certain simple degree and codegree conditions on the hypergraph $ \mathcal{H} $ and the conflicts to…

Combinatorics · Mathematics 2026-02-25 Felix Joos , Dhruv Mubayi , Zak Smith

Consider a $d$-uniform random hypergraph on $n$ vertices in which hyperedges are included iid so that the average degree is $n^\delta$. The projection of a hypergraph is a graph on the same $n$ vertices where an edge connects two vertices…

Combinatorics · Mathematics 2025-02-24 Guy Bresler , Chenghao Guo , Yury Polyanskiy , Andrew Yao

Nonsingular projective varieties which are both convex and rationally connected are considered. We ask whether such varieties must be algebraic homogeneous spaces G/P. In case X is a complete intersection, an affirmative answer is obtained…

Algebraic Geometry · Mathematics 2007-05-23 R. Pandharipande

Checkerboard surfaces in alternating link complements are used frequently to determine information about the link. However, when many crossings are added to a single twist region of a link diagram, the geometry of the link complement…

Geometric Topology · Mathematics 2016-12-21 Marc Lackenby , Jessica S. Purcell

We study various measures of irrationality for hypersurfaces of large degree in projective space and other varieties. These include the least degree of a rational covering of projective space, and the minimal gonality of a covering family…

Algebraic Geometry · Mathematics 2019-02-20 Francesco Bastianelli , Pietro De Poi , Lawrence Ein , Robert Lazarsfeld , Brooke Ullery

Many complex networks exhibit a percolation transition involving a macroscopic connected component, with universal features largely independent of the microscopic model and the macroscopic domain geometry. In contrast, we show that the…

Disordered Systems and Neural Networks · Physics 2017-06-29 Justin Coon , Carl P. Dettmann , Orestis Georgiou

We prove that every connected component of an intersection of tropical hypersurfaces contains a point of their stable intersection unless their stable intersection is empty. This is done by studying algebraic hypersurfaces that tropicalize…

Combinatorics · Mathematics 2023-02-27 Yue Ren

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

We give necessary and sufficient criteria for a smooth Enriques surface S in P^r to be scheme-theoretically an intersection of quadrics. Moreover we prove in many cases that, when S contains plane cubic curves, the intersection of the…

Algebraic Geometry · Mathematics 2013-09-25 Andreas Leopold Knutsen , Angelo Felice Lopez

We show the existence of metrically dense entire curves in rationally connected complex projective manifolds confirming for this case a conjecture according to which such entire curves on projective manifolds exist if and only if these are…

Algebraic Geometry · Mathematics 2020-01-09 Frederic Campana , Joerg Winkelmann

Two cycles on a projective variety over an algebraically closed field are shown to be rationally equivalent if and only if their difference equals a difference of complete intersections of a certain kind. Some of Bloch's conjectures for…

alg-geom · Mathematics 2008-02-03 R. Barlow

We prove analogues of several well-known results concerning rational morphisms between quadrics for the class of so-called quasilinear $p$-hypersurfaces. These hypersurfaces are nowhere smooth over the base field, so many of the geometric…

Algebraic Geometry · Mathematics 2013-11-19 Stephen Scully

We prove the "Sullivan Conjecture" on the classification of 4-dimensional complete intersections up to diffeomorphism. Here an $n$-dimensional complete intersection is a smooth complex variety formed by the transverse intersection of $k$…

Geometric Topology · Mathematics 2025-02-11 Diarmuid Crowley , Csaba Nagy

We consider the realization space of the $d$-dimensional cube, and show that any two realizations are connected by a finite sequence of projective transformations and normal transformations. We use this fact to define an analog of the…

Combinatorics · Mathematics 2019-12-23 Karim Adiprasito , Daniel Kalmanovich , Eran Nevo

We prove that a component of the closure of the set of star points on a hypersurface X of degree d>2 in N-dimensional projective space is linear. Afterwards, we focus on the case where the component is of maximal dimension N-2 and the case…

Algebraic Geometry · Mathematics 2009-09-10 Filip Cools , Marc Coppens

The article continues the study of the 'regular' arrangement of a collection of sets near a point in their intersection. Such regular intersection or, in other words, transversality properties are crucial for the validity of qualification…

Optimization and Control · Mathematics 2018-05-15 Alexander Y. Kruger

We ask when certain complete intersections of codimension $r$ can lie on a generic hypersurface in $\PP^n$. We give a complete answer to this question when $2r \leq n+2$ in terms of the degrees of the hypersurfaces and of the degrees of the…

Algebraic Geometry · Mathematics 2009-09-29 E. Carlini , L. Chiantini , A. V. Geramita

We give a new differential proof of our result on the maximal rank of generic unions of points of multiplicity two in projective space in degrees greater than five. This simplifies somewhat our proof of the Waring conjecture.

alg-geom · Mathematics 2008-02-03 J. Alexander , A. Hirschowitz

Let $k$ be the function field of a complex curve or the field $C((t))$. We show that for a smooth complete intersection $X$ of $r$ hypersurfaces in $P^n_k$ of respective degrees $d_1,...,d_r$ with $\sum d_i^2\leq n+1$ the R-equivalence on…

Algebraic Geometry · Mathematics 2009-12-04 Alena Pirutka