Questions tagged [complex-dynamics]

This tag is for questions relating to complex dynamics, study of dynamical systems defined by iteration of functions on complex number spaces. It was an area of research established by Fatou and Julia towards the beginning of the last century.

Complex dynamics concerns the iteration of analytic functions of one complex variable. Such iteration arises, for example, when solving complex equations by Newton’s method. For each function, the complex plane is divided into two fundamentally different parts – the Fatou set, where the behavior of the iterates is stable under local variation, and the Julia set, where it is chaotic. The subject of complex dynamics experienced a huge resurgence of interest in the 1980s, with the advent of computer graphics illustrating the highly intricate nature of most Julia sets, and the introduction of powerful new techniques from complex analysis leading to much profound new work.

References:

https://en.wikipedia.org/wiki/Complex_dynamics

369 questions
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Where does the series of real Mandelbrot lobes end?

In the Mandelbrot Set, c=0 has a periodicity of 1 and is surrounded by a cartoid of non-periodic points that asymptotically approach periodicty 1. Extending left along the real axis are connected lobes of respective periodicity…
Jerry Guern
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Julia sets of finite Blaschke products

Is there any book or paper where I can find a detailed discussion of the character of Julia set (Cantor set or the unit circle) depending on zeros and the constant unitary factor of a finite Blaschke product.
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Determine the ray pair at the origin of a vein in the Mandelbrot set.

In a paper I found a description of subsets of the Mandelbrot set called veins (these are also described in earlier papers by other authors, for example Chapters 20-22 of the Orsay Notes by Adrien Douady and John H. Hubbard): Given a dyadic …
Claude
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4
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1 answer

Relation between Filled Julia Set and Julia Set of a rational function

I am doing a small project in school, which is dedicated to exploring what shapes might Julia sets of rational functions take. However, as we've started investigating into the results we've got before presenting them, it turned out that what we…
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1 answer

Show that the Julia set of a function is a Cantor set

I'm asked to show that the Julia set of the function $f(z)=z^2-6$ is a Cantor set contained in $[-3,-\sqrt{3}]\cup [\sqrt{3},3]$. I have identified $3$ as a fixed point of $f$, and found that $-3,-\sqrt{3}, \sqrt{3}$ are bounded components of the…
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Converges of sequence of iterates {$z_n$} of repelling fixed point

I am following the book Iteration of Rational Functions by Alan F. Beardon. In this book, On page number 2, they are characterizing the behaviour of a sequence of iterates of the fixed point. It says that if z is a point close to the fixed point…
N_Set
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How to determine numerically where $c$ is in a mini-Mandelbrot set's filaments?

For example, how to tell efficiently which period $11$ island near a period $4$ island the coordinates $c \in \mathbb{C}$ correspond to, without tracing external rays? Ray tracing takes $O(N^2)$ time for dwell $N$; I need a more efficient algorithm…
Claude
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3 answers

Difference between limbs and bulbs in Mandelbrot Set

Taking a look to the picture of the Mandelbrot set, one immediately notice its biggest component which we call the main cardioid. This region is composed by the parameters $c$ for which $p_c$ is hyperbolic when its periodic point is a fixed point…
Joe
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2 answers

properties of the Mandelbrot set and complex dynamical system

I want to learn some knowledge about complex dynamical system, especially about the properties of Mandelbrot set, are there any literatures about this topics?
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Points $p$ in the Mandelbrot set such that $M\setminus\{p\}$ is not connected

Obviously, only the points in the boundary $p\in\partial M$ are interesting. I managed to prove a few examples: For $p=\frac 14$ the set remains connected, since $M\cap \mathbb R=[-2,\frac 14]$ and the Mandelbrot contains the main cardioid. For…
Derivative
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How to find the initial point whose sequence of iterates converges {$z_n$}?

Consider the iterration of rational function $R$($z$), Suppose the sequence of iterates {$z_n$} of initial point $z_0$ converges to $w$. Then (because $R$ is continuous at $w$), $w$ = $\displaystyle \lim_{n \to \infty}$$z_{n+1}$ =…
N_Set
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Mandelbrot set; are these trajectories chaotic?

I am using the complex Mandelbrot set, with an exponent of 2 so that the iterative equation is z = z^2 + c. The escape threshold is 4.0, and the maximum number of iterations is 5000. I find that all trajectories that belong in the set are cyclical,…
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Linear complex functions

$L_{\alpha}(z) = \alpha z$ where $z$ is a complex number and $\alpha$ is a constant and is also complex. How do I prove for $|\alpha|<1$ all orbits tend to a unique limit and how do I find this limit?
Henry
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Determine whether a point $c$ is in a wake $W_P$.

One can draw wakes in the parameter plane of the Mandelbrot set, by tracing external rays inwards from near $\infty$ (with Newton's method or other algorithm) to get polygonal outlines which can be filled. But reading the following paper I think…
Claude
  • 5,647
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Simple ways for checking if a point is not in a multibrot set

As is well-known, the Mandelbrot set (M-set for short) can be defined by considering the family of functions $f_c(z)=z^2+c$ for $c\in\mathbb{C}$, iterating them for each $c$ to obtain sequences $z_{n+1}=f_c(z_n)$ starting with $z_0=0$, and checking…
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