Questions on fractals, irregular-looking mathematical objects that display the property of self-similarity.

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Greek cross fractal

I need some code to generate a Greek cross fractal. Example: It must be made of increasingly smaller panels, but the panels may not overlap with previous panels. Does anyone know where I might ...
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1answer
73 views

Taylor series of mandelbrot bulb boundaries

What I am looking for is a way to find an approximation to the boundaries of hyperbolic components of the Mandelbrot set. I would like to be able to write a program to find the equations which ...
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1answer
47 views

Bisecting a fractal area

Simple case It is well-known that if we have a regular hexagon on a plane, then every line that passes through the centre of the circumscribed circle bisects the area of the hexagon. Extension ...
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1answer
90 views

Can you help me find a fractal drawing program?

In a previous course on chaos, the professor had us experiment with a program. The program allowed you to draw a base image (with microsoft paint like tools), then it would iterate that image under ...
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29 views

Can you help find me a particular fractal drawer? [duplicate]

In a previous course on fractals and chaos, the professor had us experiment with a program. The program allowed you to draw a base image (with microsoft paint like tools), then iterate that image ...
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2answers
67 views

How does one determine the containing boundary of a fractal?

In the Mandelbrot set, the fractal is said to be contained in the circle of radius 2. $$ z_{n+1} = {z_{n}}^{2} + c $$ I did read about a proof that showed values of 'c' beyond this circle are not ...
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1answer
144 views

How does one estimate the Hausdorff measure for arbitrary fractals, and does the constant c in $N=c\epsilon^d$ provide a good estimate?

Background: When one finds the fractal dimension of a fractal in real life, they will generally use the relation $N=c\epsilon^d$ to do so. However, the constant c is almost always neglected in ...
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1answer
25 views

Is there a hilbert curve equivalent for circles?

Is there a space-filling curve that has the same properties of a hilbert curve (two points close in 1D are close in 2D) but grows in a circular shape instead of a rectangular one?
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37 views

multifractal scaling exponent tau(q) - concave up or down?

I have read some conflicting information from two reliable sources regarding the scaling exponent in multifractal systems - tau. On the Yale website devoted to fractals, they say "Tau is a decreasing ...
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1answer
41 views

What are properties of dynamical systems in non-integer dimension spaces?

A 1D dynamical system (R1) exhibits convergence to a fixed point, or escapes to infinity. A 2D dynamical system (R3) can produce oscillations, spiral-shaped trajectories, etc. A 3D dynamical system ...
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2answers
58 views

Explicit formula for IFS fractal dimesnion

Is there an explicit formula for finding the box counting dimension of an arbitrary IFS fractal, such as the IFS fern or any other random IFS fractal? If not, is there at least a summation, or ...
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1answer
55 views

Integral over Fractals with respect to fractal dimension

I understand that there is type of integral with respect to measures that can return values when evaluated over an integral. But is there an Integral that returns d dimensional volume where d is the ...
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34 views

Are the iterates of this function bounded?

I have the function $f(z) = \sqrt z + C.$ For the value of $C = i$ (complex number), would the iterates be bounded or not? Iterating from $z = 0: f(0) = i, f(i) = \sqrt i + i$ and it goes on, ...
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15 views

Comparing fractals plant representations

After collecting data , by measuring angles and lengths of branches on some plants, i tried to represent them with L-system fractals. Let's assume that we have two plants (see below) . Those two ...
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1answer
30 views

Prove that $\mathscr{H}^0(F) = |F|$.

As stated above, I'd like to prove that the 0-dimensional Hausdorff Measure of a set $F \subset \mathbb{R}^n$ is the cardinality of $F$. In other words, that $\mathscr{H}^0 (F) = |F|$, or the number ...
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1answer
50 views

Mandelbrot Set - Predict which value of c will give bounded results?

I have been looking into the Mandelbrot set a little bit lately, and I have a question. Given the equation: $$z(n+1) = (zn)^2 + c$$ where $c$ is a complex number of the form $a+bi$ is there an easy ...
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0answers
60 views

interior distance estimate for Julia sets - getting rid of spots

From wikibooks colouring the Julia set, the distance estimate $\delta(z)$ can be calculated by: $$\begin{aligned} \delta(z) &= \lim_{n \to \infty} \frac{|z_n| \log ...
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2answers
65 views

test for membership in mandelbrot bulb of period n

Is there a efficient test (formula or inequality) of whether a given point is in a bulb of period n? In other words, something other than running the iteration a lot of times to see if it converges ...
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1answer
73 views

Numerical computation of unlimited small Julia set details

I've read the claim of a fractal image application to be able to show infinite levels of zoom for Julia sets for the classic iteration formula $z_{i+1}:=z_i^2+c$. The application has a realtime ...
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1answer
52 views

Generalizing the Apollonian Gasket to other closed curves

An Apollonian Gasket is a fractal set constructed out of tangent circles. The first stage is three mutually tangent circles (which are not all tangent at a single point). At each step, we can take a ...
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1answer
65 views

Negative Fractal dimension values in plants images

After calculating lengths and angles from a plant i represented it with the help of L-system fractals (see image below). I made that process for many plants and then i went to matlab to calculate ...
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2answers
106 views

Collage theorem to generate a spiral

I need to answer a question on fractals from the book Fractals Everywhere by M. Barsley and I have been struggling with it for a while: Use collage theorem to help you find an IFS consisting of two ...
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3answers
117 views

Is there a koch circle?

Is there some fractal like the koch snowflake, but only with many circles around a bigger initial circle, each of them surrounded by smaller circles and so on (but all of them kissing one bigger ...
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1answer
58 views

Proof of x-intersection of the Mandelbrot Set?

I'm trying to prove that the Mandelbrot set intersects the X-axis on the interval [-2,.25]. I understand and have proven that the Mandelbrot set lies in a radius of 2. Mostly, I'm wondering how to ...
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2answers
119 views

What is the algorithm hiding beneath the complexity in this paper?

So, I am a computer scientist (at least, I'm working to become one..) and I asked a question on here concerning some mathematics behind the Mandelbrot set. A reply I recieved pointed me to this paper. ...
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67 views

Bounded bessel functions in an s-set projection proof

The following is an extract from Falconer's Geometry of Fractal Sets about the proof of: "...Using the definition of a Bessel function $J_0=\frac{1}{2\pi}\int^{2\pi}_0 \cos(u \cos \theta) ...
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18 views

Identify rules for fractal L-system for plant representation using lengths and angles

As some of you already knew, to develop an L-system fractal you need some rules for angles and lengths. L-system also is well known for its application in plants. So i had a plant in the ground and ...
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1answer
43 views

Infinite number of points in the Sierpinski Triangle

I have basic background in mathematics (Linear Algebra, Calculus) and I've been reading up on fractals, because I find them fascinating. I can't understand one thing in basically all of the fractals ...
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60 views

Symmetric Icon Fractals

I have always been fascinated by fractals. But most of all I like the Symmetric Icon fractals. There is a nice book about these fractals, written by Michael Field, called Symmetry in Chaos. I'm ...
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41 views

Is there a name for the relation between Menger Sponge and Vicsek Fractal?

Both the Menger Sponge and the Vicsek Fractal in 3D can be constructed by starting with a cube, dividing it into 27 smaller cubes (3x3x3 grid), removing some of these cubes, and then applying the ...
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1answer
80 views

Finding external angles for Misiurewicz points in the Mandelbrot set

In the Mandelbrot set for the quadratic polynomial $z \to z^2 + c$, rational external angles with even denominator are pre-periodic and have corresponding external rays which land at Misiurewicz ...
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32 views

A zero-dimension set and self-referencial equation

Let $K$ be a compact set in $\mathbb{R}^2$. Let $f_1,..., f_n$ be contracting similarities of $\mathbb{R}^2$ to itself. Suposse $K$ satisfies the self-referencial equation ...
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1answer
60 views

Bounding dimension of IFS

Given the IFS $\{\frac x {2+x},\frac 2 {2+x}\}$ ($0\le x \le 1$) with attractor K prove that $0.53<\dim_HK<0.8$ I thought using the results from my last question by saying ...
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1answer
110 views

Proving ineqalities for the similarity dimension

a. Let $K$ be the attractor of the IFS $\{f_1,\dots f_n\}$ which satisfies SSC (i.e $f_i(K)\cap f_j(K)=\emptyset\forall i\neq j$) where for all $i, c_i$ such that $ 1\le i\le n, \space ...
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13 views

Reference request: Generalized Hurst Exponent

I'm looking for some references on the Generalized Hurst Exponent of a time series, more than what is on wikipedia. The Generalized Hurst Exponent, $\mathbb{H}_q$ is defined by ...
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37 views

Compact metric space implies that the hyperspace is compact

I need a hint to the following problem: If $S$ is a compact metric space then the hyperspace $H(S)$ is compact. I don't know how to begin this problem. Thanks!
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1answer
46 views

Upper Minkowski content and finite Hausdorff measure

Does someone know an example of a set $E$ with positive finite $s$-Hausdorff measure, Minkowski dimension $s$, and infinite $s$-dimensional upper Minkowski content ? The $s$-dimensional upper ...
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1answer
43 views

Minkowski dimension behaviour of sets with positive finite Hausdorff measure.

It is (rather) well known that the set \begin{equation*} E=\{k^{-1},k\in\mathbb{N}^{*}\} \end{equation*} has box-dimension $1/2$ and Hausdorff dimension $0$. However $H^{0}(E)=|E|=+\infty$. Is it ...
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1answer
48 views

Solving inverse problem related to Iterated function systems?

I generated a Barnsley's fern fractal using details in this link with the aid of MATLAB. My doubts are as follows : How do we justify the shape generated from those equations? Is it possible to ...
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2answers
133 views

Examples of bounded continuous functions which are not differentiable

Most often examples given for bounded continuous functions which are not differentiable anywhere are fractals.If we include probabilistic fractals exact self-similarity is not required. Are their ...
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1answer
49 views

Prove carpet has positive Hausdorff measure in its dimension

Given $D\subset\{0,1,2,\dots n-1\}\times\{0,\dots,m-1\}$, let $$K(D)=\{\sum_{k=1}^\infty(a_kn^{-k},b_km^{-k}):(a_k,b_k)\in D\forall k\}.$$ Show that if $D$ has uniform horizontal fibers (i.e. the ...
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1answer
151 views

Finding the location of an image of the Mandelbrot set

I've got an image of a segment of the Mandelbrot set that I generated with an iPhone app a long time ago (I use it as my background image). I now have no idea where in the set the image came from. ...
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52 views

Structure of Mandelbrot bug antennae

I have analysed the structure of of Mandelbrot set and I have understood something, but I still have some questions, mainly about antennae and little bugs. Mandelbrot set consists of the main ...
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1answer
119 views

Self-similar fractal dimension of unsymmetrial fractal

As far as I know, the following fractal has a self-similar fractal dimension of $D = -\log(3) / \log(1/2) = 1.5850$ But what is the fractal dimension of the following fractal (4 times the fractal ...
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5answers
517 views

If $f(x)=x^2-x-1$ and $f^n(x)=f(f(\cdots f(x)\cdots))$, find all $x$ for which $f^{3n}(x)$ converges.

Let $f:\mathbb{R}\to\mathbb{R}$ be the polynomial defined by $$f(x)=x^2-x-1$$ and let $$g_0(x)=f(x),\quad g_1(x)=f(f(x)),\quad\ldots\quad g_n(x)=f(f(f(\cdots f(x)\cdots)))$$ The positive root of ...
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3answers
388 views

Simplifying $\sqrt {1+\sqrt 5}$

I considered simplifying $\sqrt {1+\sqrt 5}$. So I started $(a+b \sqrt 5)^2 = 1 + \sqrt 5$. This gave me $a\color{blue}{^2} + 5b^2 =1 , 2ab = 1$ so the result was $ \sqrt{1+\sqrt 5} = \sqrt{1/2 - ...
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2answers
57 views

How do I prove the circumference of the Koch snowflake is divergent?

How do I prove that the circumference of the Koch snowflake is divergent? Let's say that the line in the first picture has a lenght of $3cm$. Since the middle part ($1cm$) gets replaced with a ...
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1answer
143 views

Convex hull of the Mandelbrot set

What is the convex hull of the Mandelbrot set? I know that the leftmost point is $c=-2$ and I thought the extreme vertical points were $c=\pm i$. Sheldon's answers says they're not. I think that the ...
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0answers
63 views

Every projection of the square of the middle thirds Cantor set contains an interval

Let $C_\lambda$ the cantor set which is defined by the IFS $\{\lambda x,\lambda x+(1-\lambda)\}$ and also let $E=C_\lambda\times C_\lambda$.Suppose $\lambda =\frac 1 3$, we get the standard ...
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53 views

Slightly Chunky Cantor Sets

I'm familiar with the construction of so-called "fat" Cantor sets (e.g. the Volterra construction), where a Cantor-type construction is used to construct a nowhere-dense set of positive Lebesgue ...