Results 11 to 20 of about 81,984 (133)
Inverse problems for invariant algebraic curves: explicit computations
Given an algebraic curve in the complex affine plane, we describe how to determine all planar polynomial vector fields which leave this curve invariant.
C. Christopher +3 more
semanticscholar +1 more source
Characteristic Number: Theory and Its Application to Shape Analysis
Geometric invariants are important for shape recognition and matching. Existing invariants in projective geometry are typically defined on the limited number (e.g., five for the classical cross-ratio) of collinear planar points and also lack the ability ...
Xin Fan +5 more
doaj +1 more source
Unique ergodicity for foliations in $$\mathbb {P}^2$$P2 with an invariant curve [PDF]
Consider a foliation in the projective plane admitting a projective line as the unique invariant algebraic curve. Assume that the foliation is generic in the sense that its singular points are hyperbolic. We show that there is a unique positive $${dd^c}$$
T. Dinh, N. Sibony
semanticscholar +1 more source
Quadratic systems with a symmetrical solution
In this paper we study the existence and uniqueness of limit cycles for so-called quadratic systems with a symmetrical solution: \begin{equation*} \begin{split} \frac{dx(t)}{dt}& = P_2(x,y) \equiv a_{00}+a_{10}x+a_{01}y+a_{20}x^2+a_{11}xy+a_{02}y^2 ...
Andre Zegeling, Robert Kooij
doaj +1 more source
Necessary conditions for the existence of invariant algebraic curves for planar polynomial systems
This work deals with planar polynomial differential systems { x ˙ } = P ( x , y ) , { y ˙ } = Q ( x , y ) . We give a set of necessary conditions for a system to have an invariant algebraic curve.
J. Chavarriga, H. Giacomini, M. Grau
semanticscholar +1 more source
Algebraic curves with many automorphisms [PDF]
Let $X$ be a (projective, geometrically irreducible, nonsingular) algebraic curve of genus $g \ge 2$ defined over an algebraically closed field $K$ of odd characteristic $p$.
M. Giulietti, G. Korchmáros
semanticscholar +1 more source
The Ceresa class and tropical curves of hyperelliptic type
We define a new algebraic invariant of a graph G called the Ceresa–Zharkov class and show that it is trivial if and only if G is of hyperelliptic type, equivalently, G does not have as a minor the complete graph on four vertices or the loop of three ...
Daniel Corey, Wanlin Li
doaj +1 more source
Invariant Algebraic Curves and Rational First Integrals for Planar Polynomial Vector Fields
We present three main results. The first two provide sufficient conditions in order that a planar polynomial vector field in C2 has a rational first integral, and the third one studies the number of multiple points that an invariant algebraic curve of ...
J. Chavarriga, J. Llibre
semanticscholar +1 more source
Invariant algebraic curves of large degree for quadratic system
In this paper we present for the first time examples of algebraic limit cycles and saddle loops of degree greater than 4 for planar quadratic systems. In particular, we give examples of algebraic limit cycles of degree 5 and 6, and algebraic saddle loops
C. Christopher, J. Llibre, G. Swirszcz
semanticscholar +1 more source
On the algebraic invariant curves of plane polynomial differential systems [PDF]
We consider a plane polynomial vector field $P(x,y)dx+Q(x,y)dy$ of degree $m>1$. To each algebraic invariant curve of such a field we associate a compact Riemann surface with the meromorphic differential $\omega=dx/P=dy/Q$. The asymptotic estimate of the
Alexei Tsygvintsev
semanticscholar +1 more source

