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Related papers: Incidences among flows

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Let $P$ be a set of $m$ points and $L$ a set of $n$ lines in $\mathbb R^4$, such that the points of $P$ lie on an algebraic three-dimensional surface of degree $D$ that does not contain hyperplane or quadric components, and no 2-flat…

Combinatorics · Mathematics 2016-09-29 Micha Sharir , Noam Solomon

We show that the number of incidences between $m$ distinct points and $n$ distinct lines in ${\mathbb R}^4$ is $O\left(2^{c\sqrt{\log m}} (m^{2/5}n^{4/5}+m) + m^{1/2}n^{1/2}q^{1/4} + m^{2/3}n^{1/3}s^{1/3} + n\right)$, for a suitable…

Combinatorics · Mathematics 2015-03-26 Micha Sharir , Noam Solomon

We present some elementary ideas to prove the following Sylvester-Gallai type theorems involving incidences between points and lines in the planes over the complex numbers and quaternions. (1) Let A and B be finite sets of at least two…

Combinatorics · Mathematics 2009-03-12 Jozsef Solymosi , Konrad J. Swanepoel

A regular linear line complex is a three-parameter set of lines in space, whose Pl\"ucker vectors lie in a hyperplane, which is not tangent to the Klein quadric. Our main result is a bound $O(n^{1/2}m^{3/4} + m+n)$ for the number of…

Combinatorics · Mathematics 2021-07-01 Misha Rudnev

Families of $N$ interacting curves are considered, with long range, mean field type, interaction. A family of curves defines a 1-current, concentrated on the curves, analog of the empirical measure of interacting point particles. This…

Analysis of PDEs · Mathematics 2017-02-01 Hakima Bessaih , Michele Coghi , Franco Flandoli

This paper addresses the problems of spline interpolation on smooth Riemannian manifolds, with or without the inclusion of least-squares fitting. Our unified approach utilizes gradient flows for successively connected curves or networks,…

Optimization and Control · Mathematics 2025-10-29 Chun-Chi Lin , Dung The Tran

A general, two-way coupled, point-particle formulation that accounts for the disturbance created by the dispersed particles in obtaining the undisturbed fluid flow field needed for accurate computation of the force closure models is…

Fluid Dynamics · Physics 2021-06-02 Pedram Pakseresht , Sourabh V. Apte

We consider classical curvature flows: 1-parameter families of convex embeddings of the 2-sphere into Euclidean 3-space which evolve by an arbitrary (non-homogeneous) function of the radii of curvature. The associated flow of the radii of…

Differential Geometry · Mathematics 2020-07-14 Brendan Guilfoyle , Wilhelm Klingenberg

In this paper, we define some new associated curves as integral curves of a vector field generated by Frenet vectors of tangent indicatrix of a curve in Euclidean 3-space. We give some relationships between curvatures of these curves. By…

Differential Geometry · Mathematics 2019-10-16 Burak Sahiner

We investigate vertices for plane curves with singular points. As plane curves with singular points, we consider Legendre curves (respectively, Legendre immersions) in the unit tangent bundle over the Euclidean plane and frontals…

Differential Geometry · Mathematics 2024-06-25 Nozomi Nakatsuyama , Masatomo Takahashi

We generalize two classical formulas for complete intersection curves by introducing the the complete intersection discrepancy of a curve as a correction term. The first is a well-known multiplicity formula in singularity theory, due to…

Algebraic Geometry · Mathematics 2026-04-07 Andrei Benguş-Lasnier , Antoni Rangachev

Curves in ${\mathbb R}^n$ for which the ratios between two consecutive curvatures are constant are characterized by the fact that their tangent indicatrix is a geodesic in a flat torus. For $n= 3,4$, spherical curves of this kind are also…

Differential Geometry · Mathematics 2007-05-23 J. Monterde

Let f = 0 be an implicit singular plane curve. When deforming f = 0, inflections and vertex emerge from the singularities. In this papper, we classify the deformations of f = 0 with respect to the inflections and the vertices in the cases…

Differential Geometry · Mathematics 2025-02-28 Marco Antônio do Couto Fernandes , Samuel Paulino dos Santos

We give an exponential upper and a quadratic lower bound on the number of pairwise non-isotopic simple closed curves can be placed on a closed surface of genus g such that any two of the curves intersects at most once. Although the gap is…

Geometric Topology · Mathematics 2013-01-04 Justin Malestein , Igor Rivin , Louis Theran

In this paper, flows of a viscid fluids on curves are considered. Symmetry algebras and the corresponding fields of differential invariants are found. We study their dependence on thermodynamic states of media, and provide classification of…

Fluid Dynamics · Physics 2020-06-29 Anna Duyunova , Valentin Lychagin , Sergey Tychkov

We prove bounds on approximate incidences between families of circles and families of points in the plane. As a consequence, we prove a lower bound for the dimension of circular $(u,v)$-Furstenberg sets, which is new for large $u$ and $v$.

Classical Analysis and ODEs · Mathematics 2025-02-18 John Green , Terence L. J. Harris , Yumeng Ou , Kevin Ren , Sarah Tammen

We define a computable topological invariant $\mu(\gamma)$ for generic closed planar regular curves $\gamma$, which gives an effective lower bound for the number of inflection points on a given generic closed planar curve. Using it, we…

Differential Geometry · Mathematics 2011-03-18 Shuntaro Ohno , Tetsuya Ozawa , Masaaki Umehara

We prove a point-wise and average bound for the number of incidences between points and hyper-planes in vector spaces over finite fields. While our estimates are, in general, sharp, we observe an improvement for product sets and sets…

Classical Analysis and ODEs · Mathematics 2007-07-31 Derrick Hart , Alex Iosevich , Doowon Koh , Misha Rudnev

The point-line incidence problem has been widely studied in Euclidean spaces and vector spaces over finite fields, whereas the analogous problem has rarely been considered over finite $p$-adic rings. In this paper, we investigate incidences…

Combinatorics · Mathematics 2025-10-24 Yuhan Chu

Flows of vector fields are an essential tool in differential geometry, with countless applications in both theory and practice. While they have been extensively studied for ordinary manifolds and supermanifolds, a treatment of flows in…

Differential Geometry · Mathematics 2026-05-25 Rudolf Smolka , Jan Vysoky