The Mandelbrot Set – What It Is and How It Works.
The Mandelbrot Set is a mathematical curiosity with infinite complexity. The pages of this
section of this website are to demonstrate the complexity and beauty of the Mandelbrot Set
 
The Mandelbrot set is derived from iterations of a rather simple equation for numbers in a complex
number plane. The iterated equation is: "z
n+1 = z
n2 + c", where
at the start z
0 = 0 and “c” is a complex number (having two-dimensions) representing
points of the number plain (in this case the display area of the screen), and is expressed in the
following form: “0.7075+0.3088i”. The first part of the number “0.7075” is known as the real
component (x-axis) and the second part “0.3088i” is known as the imaginary component (y-axis).
And the “i” represents the square root of -1 (√-1). To clarify things, the √-1 is a
number that is at right angles to the number line, thus creating the number plane.
 
To square the complex number “z” we must multiply all the components of the complex number.
For example: (0.7075+0.3088i) * (0.7075+0.3088i). Let’s replace “z” with the “x” and “y” component.
 
z
next = z
2 + c   becomes   z
next = (x + y) * (x + y) + cx + cy
 
We expand this to   z
next = x
2 + 2xy + y
2 + cx + cy
 
Now we must now separate the real from the imaginary:
 
x
next = x
2 - y
2 + cx
y
next = 2xy + cy
 
Note that i
2 = -1 therefore y
2 becomes a real number, but negative.
And where x is muntiplied by i, it becomes an imaginary number.
 
I feel that it is important to say that this complex numbers methodology is used extensively in
engineering particularly in electrical engineering with AC circuits, telecommunications, mechanical
& structural engineering, fluid dynamics and aerospace, etc. This is a very real system and not
just something to draw pretty patterns.
 
Core Concept: "Stay Small or Tend Toward Infinity"
For this image to be generated, each and every pixel on the display area represents a
single point on the number plane and this calculation is done multiple times until either
the resulting value of “z” tends toward infinity or results in “z” stays small when we
reach the computation limit. Numbers for “c” that remain small are part of the Mandelbrot
Set; numbers that tend toward infinity are not part of the Mandelbrot Set.
 
We know that the number will tend toward infinity if the number crosses a circle that has
a radius of 2 from the 0+0i point. The number of iterations that it takes to cross that
circle will determine the colour of that single pixel. As you can imagine, if we have a
display area, say 1200x900, there are a lot of calculators to be done.
 
Colour of Numbers in the Set
Normally the colour of numbers in the set (the numbers that stay small) are coloured black.
However, in some colour maps in these pages (and in other sites or programs), numbers in
the set are coloured white. Within these pages you are also given the option to change
that colour to anything you choose.
 
The Rules
Experiment, explore options, do different things and see what happens, gain understanding,
be creative, share it with your friends, but most of all have fun.
 
Having my say
Don’t shy away from getting understanding, it will equip you for living life. God designed
you with an enquiring mind, and He intended us to use that mind to gain understanding and
perhaps even understand Him. When He laid out the foundations of the universe, He set out
the laws of physics and mathematics. He intended us to explore and understand. Jesus is King.
 
Licence
Images generated from this site for private purposes are free to use as you feel fit without
cost. Feel free to share the images with your friends and family, make that coffee mug for your
grandmother, a print for a sibling, a t-shirt for your nephew, etc. I only ask that you share
this site with friends and family so that others can also have fun exploring the world of mathematics.
 
If you intend to use the product for commercial purposes, such as printing on a t-shirt, mugs etc
to sell as a product, or for a business logo, or any other commercial purpose, then I ask that you
get in contact with me. A lot of work has gone into making this program and it is only right that
money is to be made from this, then the one who has written the software should get a small portion
of the proceeds.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© 2026 Richard Faulks. All Rights Reserved.