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In this paper we investigate the continuum limits of a class of Markov chains. The investigation of such limits is motivated by the desire to model very large networks. We show that under some conditions, a sequence of Markov chains…

Networking and Internet Architecture · Computer Science 2011-06-22 Yang Zhang , Edwin K. P. Chong , Jan Hannig , Donald Estep

Many classical results in algebraic geometry arise from investigating some extremal behaviors that appear among projective varieties not lying on any hypersurface of fixed degree. We study two numerical invariants attached to such…

Algebraic Geometry · Mathematics 2019-06-20 Edoardo Ballico , Emanuele Ventura

We get sharp degree bound for generic smoothness and connectedness of the space of conics in low degree complete intersections which generalizes the old work about Fano scheme of lines on Hypersurfaces.

Algebraic Geometry · Mathematics 2013-07-25 Hong R. Zong

Hilbert curves of special varieties like Fano manifolds of low coindex as well as fibrations having such a manifold as general fiber, endowed with appropriate polarizations, are investigated. In particular, all most relevant varieties…

Algebraic Geometry · Mathematics 2018-03-06 Antonio Lanteri , Andrea Luigi Tironi

The present paper attempts to show an alternative approach with regards to rational Pythagorean-hodograph (PH) curves and especially more natural approach for rational PH helices (i.e. rational helices). It exploits geometric features of…

Differential Geometry · Mathematics 2014-01-28 Fatma Şengüler-Çiftçi

We prove some results on the fibers and images of rational maps from a hyper-K\"ahler manifold. We study in particular the minimal genus of fibers of a fibration into curves. The last section of this paper is devoted to the study of the…

Algebraic Geometry · Mathematics 2022-08-23 Claire Voisin

How much cutting is needed to simplify the topology of a surface? We provide bounds for several instances of this question, for the minimum length of topologically non-trivial closed curves, pants decompositions, and cut graphs with a given…

Combinatorics · Mathematics 2015-04-08 Éric Colin de Verdière , Alfredo Hubard , Arnaud de Mesmay

The primary objects of study in the ``knot theory of complex plane curves'' are C-links: links (or knots) cut out of a 3-sphere in the complex plane by complex plane transverse and totally tangential. Transverse C-links are naturally…

Geometric Topology · Mathematics 2007-05-23 Lee Rudolph

Given an undirected, edge-weighted graph G together with pairs of vertices, called pairs of terminals, the minimum multicut problem asks for a minimum-weight set of edges such that, after deleting these edges, the two terminals of each pair…

Data Structures and Algorithms · Computer Science 2016-11-24 Éric Colin de Verdière

The goal of this short note is to point out that every Fano manifold with a nef tangent bundle possesses an almost K{\"a}hler-Einstein metric, in a weak sense. The technique relies on a regularization theorem for closed positive (1,…

Complex Variables · Mathematics 2018-02-07 Jean-Pierre Demailly

In statistical inference problems, we wish to obtain lower bounds on the minimax risk, that is to bound the performance of any possible estimator. A standard technique to obtain risk lower bounds involves the use of Fano's inequality. In an…

Information Theory · Computer Science 2018-04-06 Ramji Venkataramanan , Oliver Johnson

A wealth of literature exists on computing and visualizing cuts for the magnetic scalar potential of a current carrying conductor via Finite Element Methods (FEM) and harmonic maps to the circle. By a cut we refer to an orientable surface…

Computational Physics · Physics 2019-06-19 Alex Stockrahm , Valtteri Lahtinen , Jari J. J. Kangas , P. Robert Kotiuga

It is well known that an irreducible algebraic curve is rational (i.e. parametric) if and only if its genus is zero. In this paper, given a tolerance $\epsilon>0$ and an $\epsilon$-irreducible algebraic affine plane curve $\mathcal C$ of…

Algebraic Geometry · Mathematics 2014-01-08 Sonia Perez-Diaz , Sonia L. Rueda , Juana Sendra , J. Rafael Sendra

In this paper we give a splitting criterion for uniform vector bundles on Fano manifolds covered by lines. As a consequence, we classify low rank uniform vector bundles on Hermitian symmetric spaces and Fano bundles of rank two on…

Algebraic Geometry · Mathematics 2015-03-10 Roberto Munoz , Gianluca Occhetta , Luis E. Sola Conde

In this paper we try to further explore the linear model of the moduli of rational maps. Our attempt yields following results. Let $X\subset \mathbf P^n$ be a generic hypersurface of degree $h$. Let $R_d(X, h)$ denote the open set of the…

Algebraic Geometry · Mathematics 2015-01-27 Bin Wang

Manifolds discovered by machine learning models provide a compact representation of the underlying data. Geodesics on these manifolds define locally length-minimising curves and provide a notion of distance, which are key for reduced-order…

Machine Learning · Computer Science 2023-05-25 Daniel Kelshaw , Luca Magri

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

We exhibit planar, rational curves of large degree over ${\mathbb F}_2$ that have a unique singular point, which has multiplicity 2. In characteristic 0 such curves exist only for degrees up to $6$. v.2: references updated and examples of…

Algebraic Geometry · Mathematics 2026-04-21 János Kollár

Using deformation theory of rational curves, we prove a conjecture of Sommese on the extendability of morphisms from ample subvarieties when the morphism is a smooth (or mildly singular) fibration with rationally connected fibers. We apply…

Algebraic Geometry · Mathematics 2020-11-23 Tommaso de Fernex , Chung Ching Lau

We prove the Manin-Peyre conjecture for the number of rational points of bounded height outside of a thin subset on a family of Fano threefolds of bidegree (1,2). The proof uses a mixture of the circle method and techniques from the…

Number Theory · Mathematics 2022-07-18 Dante Bonolis , Tim Browning , Zhizhong Huang