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

learn more… | top users | synonyms

8
votes
2answers
86 views

Examples of smooth fractals

A classic example of a fractal curve is the Koch Snowflake. This is a topological manifold (as opposed to many other fractals which are not), but it also clearly not smooth. Question: Are there ...
0
votes
1answer
21 views

How would I calculate points on the Peano curve?

The Peano curve is often given as an example of a space filling curve which maps the unit line to the unit square. So, it is a function of the form $[0,1] \rightarrow [0,1]^2$? In which case can I ...
22
votes
2answers
265 views

Fractal dimension of the function $f(x)=\sum_{n=1}^{\infty}\frac{\mathrm{sign}\left(\sin(nx)\right)}{n}$

Consider the function $$ f(x)=\sum_{n=1}^{\infty}\frac{\mathrm{sign}\left(\sin(nx)\right)}{n}\, . $$ This is a bizarre and fascinating function. A few properties of this function that SEEM to be true: ...
6
votes
1answer
79 views

Perfect circles in the Mandelbrot set?

It is known that the boundary of the period 2 hyperbolic component of the Mandelbrot set is a perfect circle of radius $\frac{1}{4}$ centered at $-1$. Moreover it is known that the boundaries of the ...
2
votes
2answers
42 views

Radius of inner circles given radius of outer circle and number of inner circles in circular fractal

I am trying to create a circular fractal in which each circle is composed by a given number $n$ of smaller circles. It would look something like this for $n = 8$: However, I don't know how to ...
2
votes
1answer
41 views

Sierpinski triangle formula: How to take into account for 0th power?

The formula to count Sierpinski triangle is 3^k-1 .It is good if you don't take the event when k=0.But how can you write a more ...
2
votes
1answer
47 views

Minkowski Dimension of Special Cantor Set

As can be seen at the top of the page here (exercise 1), Terry Tao gives an exercise to find the Minkowski Dimension of the Quadnary Cantor Set, and of a special Quadnary Cantor Set. The two sets are:...
1
vote
1answer
17 views

Hausdorff dimension of a Cantor Set: attaining a lower bound

I'm considering the problem of calculating the Hausdorff dimension of a Cantor set, according to the following lemmas: Lemma 1 Let $C: [0, 1] \rightarrow [0, 1]$ be a Cantor staircase function. Then ...
1
vote
1answer
34 views

a conundrum regarding integrated Brownian motion and fractals

Let $X(t)$ be a Brownian motion. I know that the integral \begin{equation} Y(t) = \int_0^t d\tau ~ X(\tau) \end{equation} is well-defined, since Brownian motion $X(\tau)$ is a.s. continuous. Thinking ...
4
votes
0answers
75 views

Fractal identification

I was trying different algorithms out, and after a while, I found this fractal: The generation has similarities to Koch's curve, but instead of putting triangles on triangles, I put circles on top ...
1
vote
0answers
40 views

Hausdorff metric between attractor sets of iterated functions systems

Let the set $X:=\{(x,y)\in \mathbb{R}^{2}:0\leq x\leq 1,0\leq y\leq 1-x\}$ and for each positive integer $i$ and $j\in\{1,\ldots,2^{i}-1\}$ define the contracttion $f_{ij}:X\longrightarrow X$ by $f_{...
3
votes
0answers
66 views

Integral over Julia Set (Is my math correct?)

So I was answering this question about whether or not the Julia Set was self-similar in a known way. Of course it is, and that got me thinking. Even though the self similarity is nonlinear, what if ...
2
votes
1answer
69 views

Can a “Julia set” fractal be described in a “closed form”?

What I mean by that is, consider, say, the "Koch snowflake" curve. It is formed by repeatedly applying a substitution to the lines of a triangle to get the final curve in the limit. What I am after ...
0
votes
0answers
21 views

Interpretation of $ \tau $ in the Stephen Astels paper '' Cantor set and numbers with restricted partial quotients?

I am trying to read Stephen Astels paper 'Cantor sets and numbers with restricted partial quotients'. Visit http://www.ams.org/journals/tran/2000-352-01/S0002-9947-99-02272-2 In this he directly ...
3
votes
0answers
20 views

What algorithm can be used to reconstruct a self similar time series from a portion of it?

I am working on a process which produces time series similar to the one shown in the graph below: I calculated Fractal dimension $D$ and Generalised Hurst Exponent $H$, to confirm that equality $D=...
5
votes
0answers
110 views

Arithmetic implications of different ways to geometrically construct an Hilbert's curve

I have a question on the relation between the geometric and the arithmetic representation of the Hilbert's space-filling curve. Geometric representation: consider the Hilbert's curve $f_h:[0,1]\...
1
vote
0answers
22 views

On the construction os a space-filling curve by interpolation fractals functions

I'am trying to construct a space-filling curve in the unit square $I^{2}:=[0,1]\times [01,]$ following the results shown in the Barnsley's book "Fractals Everywhere". Thus, let $\Delta:=\big\{ (0,0),(...
0
votes
0answers
15 views

What are the Geometric Properties of Non Integer Vector Spaces?

I found a paper from Princeton called "Axiomatic Basis for Spaces with Non Integer Dimension" that presents five axioms and then starts to create a framework similar to what I'd think the subject ...
3
votes
2answers
41 views

Hausdorff dimension via ergodic theory

This is definitely a soft question, but it was recently mentioned to me that one can study the dimension of fractals via ergodic methods. I'm familiar with ergodic theory on about the level of ...
7
votes
0answers
203 views

Pythagoras tree bounding size

The Pythagoras tree is a fractal generated by squares. For each square, two new smaller squares are constructed and connected by their corners to the original square. The angle of the triangle formed ...
1
vote
1answer
53 views

Geometric generation principle form constructing the Hilbert Curve

I have some questions on the generation of the Hilbert's space-filling curve. Any help to clarify doubts a-e would be very appreciated. The Hilbert's space-filling curve is a function $f_h:[0,1]\...
0
votes
1answer
85 views

Continuous or Differentiable but Nowhere Lipschitz Continuous Function

What is a real valued function that is continuous on a close interval but not Lipschitz continuous on any subinterval? What is a real valued function that is differentiable on a close interval but not ...
52
votes
4answers
5k views

Does this Fractal Have a Name?

I was curious whether this fractal(?) is named/famous, or is it just another fractal? I was playing with the idea of randomness with constraints and the fractal was generated as follows: Draw a ...
18
votes
3answers
277 views

What is the moment of inertia of a Gosper island?

We know that regular hexagons can tile the plane but not in a self-similar fashion. However we can construct a fractal known as a Gosper island, that has the same area as the hexagon but has the ...
0
votes
0answers
26 views

Is there a there a non intersecting mapping to unit square.

Is there a way to go from the fat cantor set to a half unit square in a non intersecting way using Hilberts curve? How would I go about constructing a non intersecting space filling curve of non zero ...
3
votes
1answer
116 views

Is a hypersphere of non-integer dimension a fractal?

Thanks to the gamma function the formula for the surface of a unit http://mathworld.wolfram.com/Hypersphere.html $$ S(n) = \frac{2 \pi^{n/2}}{\Gamma(n/2)} $$ allows to calculate the surface of a ...
0
votes
0answers
18 views

Sierpinski gasket is the closure of a set of its vertices

Why Sierpinski gasket is the closure of a set of its vertices? Let $V_0:=\{0=p_0, p_1, p_2\}$ be vertices of an equilateral triangle, and let $\hat {\mathcal H} := \bigcup_{i=0,1,2}(- + p_i)/2$ (...
1
vote
1answer
41 views

IFS which construct this fractal and have affine transformation only

[Image updated] Is there an IFS which construct this fractal and have affine transformation only? (I think there must be a restriction, which is not an affine transformation. Can it be proved?)
1
vote
0answers
18 views

When the self-similar dimension and the Hausdorff dimension are different?

By the en.wikipedia, for the self-similar sets in a metric space, the self-similar dimension and the Hausdorff dimension are often the same, but not always. Is there a known sufficient-necessary ...
7
votes
1answer
92 views

What is the shortest path to a “little Mandelbrot” from $i$?

As you all already know, the Mandelbrot set has little "copies" of itself strewn throughout the boundary region (some of them distorted somewhat), and these are all connected. The point $i$ (or $x = ...
2
votes
1answer
27 views

Exact value of Hausdorff measure of middle-third Cantor set

Is there any result about the exact value of $\log_3 2$-dimensional Hausdorff measure of the middle-third Cantor set? And is there any fractal (in $\mathbb R^n$) which is not contained in a $p$-...
0
votes
0answers
37 views

What´s the dimension of a Sierpinski fractal?

I know the dimension of a Koch snowflake (log4/log3), but what numbers do I have to put in to obtain the dimension of a Sierpinski fractal?
2
votes
1answer
49 views

What is the condensation set of a fractal?

Is there a definition of the condensation set of a fractal that is both clear and rigorous? I've been searching around to get a sense of what exactly the condensation set of a fractal is - I've ...
6
votes
1answer
73 views

Can the fractal dimension of a surface be less than 2?

I have two surfaces represented as raster images with heights as grayscale values. One is natural landscape elevations; the other is just distance from a line. I have computed Minkowsky D = 2 - H ...
1
vote
0answers
29 views

How was one derivied from the other?

In the geological paper entitled The power–law relationship between landslide occurrence and rainfall level by C. Li et al, a power-law cumulative probability distribution is derived. However, I don't ...
0
votes
1answer
32 views

How to determine constant $C$ in $p(x) = Cx^{-D}$?

Given a distribution obeying the power-law (fractal) relation, such as the cumulative distribution function $L_{cf}(> X) = CR^{-D}$, if $X$ is given, how does one find the constant $C$ from a given ...
1
vote
0answers
56 views

Scaling factor closest to 1 in an infinite sequential rectangle packing

The Ammann Chair can be used in an infinite dissection of a rectangle, where the pieces have a scaling factor of $ k = 1/\sqrt{\phi} = 0.786151...$. The largest piece has area $\sqrt{5}$ and longest ...
0
votes
2answers
61 views

hyperbolic spaces and fractals

Is there a relation between hyperbolic spaces and fractals? In group theory, if we take the Cayley graph of a free group on two generators, we get a fractal quaternary tree, which I'd like to think as ...
4
votes
1answer
80 views

Is this a valid definition of “self-similar fractal”?

I have always been fascinated by self-similarity, particularly in fractals. I was always wanted to find a simple definition of a self-similar fractal. Of course, saying "is self-similar, and is a ...
2
votes
1answer
40 views

Why c>1/4 is not in Mandelbrot set

As title: $f_c(x)=x^2+c$ I got to the step: $f_c(x)>x$ (for all x) But what's next? How to show that after k iterations, $f^k_c \to \infty$ as $k \to \infty$ Thanks,
3
votes
1answer
67 views

Fractal fundamentals

I am a programmer by trade, and am very interested in fractals. To be very basic about the concept, one might say a 'circle of circles' is a fractal. Where each circle is made up of circles, and ...
2
votes
1answer
86 views

Is every basin of attraction completely invariant?

I can't seem to find a definitive answer in the literature. I believe the answer is yes, but my focus has been on the rational maps on the Riemann sphere. At the very least I'm confident that if the ...
0
votes
1answer
61 views

Is there a general metod to construct a fractal?

I would like to construct a fractal (traditional, self-affine, and fat fractal) with a given embedding and fractal dimension, but I don't know how to do it programmatically. The shape of the fractal ...
1
vote
0answers
41 views

How to generate/validate unique fractal?

There are many known fractals that exist such as Mandelbrot, Cantor set, or the Koch curve, Sierpinski Triangle. What I am curious about, is how one could go about creating their own, unique fractal ...
5
votes
1answer
90 views

How is this fractal produced?

It is stated here: Iterating the above optimized map $$f(z)=\frac{1}{4}(1 + 4z - (1 + 2z)\cos(\pi z))$$in the complex plane produces the Collatz fractal. The point of view of iteration on ...
2
votes
0answers
36 views

Is the generalized mandelbrot set a fractal in the $d$ dimension?

The $d$-mandelbrot set is defined as the set of $c$ such that the iterations of $$z \mapsto z^d + c$$ starting with $z=0$ is bounded in absolute value. Here is a picture of the mandelbrot sets from $...
0
votes
0answers
32 views

On a formulation in Hilberts original paper about the space-filling Hilbert curve

I have a question on the famous paper Über die stetige Abbildung einer Linie auf ein Flächenstück (which translates roughly as On the continuous mapping of a line onto a square) by D. Hilbert. Let the ...
2
votes
1answer
58 views

Is there a plane filling function calculator online?

I recently read about the "Hilbert Curve" and found it very interesting. Does anyone know of a place online where I could extrapolate different shapes and explore this field of mathematics?
1
vote
0answers
46 views

Deriving convergence region of iterative formula

A year ago I asked this question about fractal icons, however I didn't get any wiser yet. Now I am trying to understand the convergence of a simplified version of the fractal, to learn more about the ...
18
votes
0answers
181 views

Has this chaotic map been studied?

I have recently been playing around with the discrete map $$z_{n+1} = z_n - \frac{1}{z_n}$$ That is, repeatedly mapping each number to the difference between itself and its reciprocal. It shows some ...