Nepedia
Back to Discover
Advanced Reader
🔢

Fractal

math Maturity 11-13 Next article →

A fractal is a complex geometric shape that contains detailed structure at any scale.

Mandel zoom 00 mandelbrot set
Mandel zoom 00 mandelbrot set

While traditional shapes like circles or squares become smooth when magnified, fractals reveal new details the closer you look. This characteristic is known as self-similarity. It means that small parts of the shape look similar to the whole object.

Sierpinski carpet 6
Sierpinski carpet 6

Some fractals exhibit affine self-similarity, where the replication is an exact copy at every scale, such as in the Menger sponge. This makes fractals a unique way to study how patterns repeat across different sizes.

To understand how fractals function, one must look at how they scale. In standard geometry, scaling follows integer dimensions. If you double the edge of a square, its area increases by four, which is two raised to the power of two. If you double the radius of a sphere, its volume increases by eight, which is two raised to the power of three.

Simple Fractals
Simple Fractals

Fractals do not follow these whole-number rules. When a fractal's length is doubled, its spatial content scales by a power that is often a non-integer. This value is called the fractal dimension, or the Hausdorff dimension. It is used to distinguish the fractal's complexity from its topological dimension, which is its conventional dimension.

There are several ways to categorize these mathematical constructs. One type is the self-similar fractal, where parts are reduced-size copies of the whole. Another category includes the Koch curve, which can be described by the specific math $3^D = 4$ to find its dimension.

Von Koch curve
Von Koch curve

Some fractals are also described as being "nowhere differentiable." This means they are so jagged and irregular that they cannot be measured with traditional straight-line tools. For example, an infinite fractal curve like the Koch snowflake has an infinite perimeter. You could never use a tape measure to find its length because every tiny segment contains more wiggles and bumps.

The history of fractal mathematics began with early ideas of recursion. In the 17th century, Gottfried Leibniz pondered recursive self-similarity, though he incorrectly believed only straight lines could be self-similar. For a long time, these irregular shapes were dismissed by mathematicians as "monsters."

Cantor set in seven iterations
Cantor set in seven iterations

The field changed in 1872 when Karl Weierstrass presented a function that was continuous but nowhere differentiable. Shortly after, in 1883, Georg Cantor published his work on Cantor sets. These researchers provided the rigorous foundation needed to move beyond simple geometric patterns into complex analysis.

Further milestones occurred throughout the early 20th century. In 1904, Helge von Koch created the geometric definition of the Koch snowflake.

Von Koch curve
Von Koch curve

Wacław Sierpiński constructed his famous triangle and carpet between 1915 and 1916. During this same era, Pierre Fatou and Gaston Julia studied how complex numbers and iterative functions create fractal behavior.

Julia set (indigo)
Julia set (indigo)

By 1918, Felix Hausdorff expanded the mathematical definition of dimension. These individual discoveries eventually merged into a cohesive study of complex, fragmented shapes.

Benoît Mandelbrot is the figure who brought these ideas into the modern era. He coined the term "fractal" in 1975, deriving it from the Latin word *fractus*, meaning broken or fractured.

Mandelbrot 12 Encirclements
Mandelbrot 12 Encirclements

Mandelbrot provided various definitions for fractals, ranging from highly technical descriptions of the Hausdorff–Besicovitch dimension to simpler ideas about fragmented shapes. He famously described fractals as "beautiful, damn hard, increasingly useful." His work allowed mathematicians to use fractal dimensions as a generic term for various natural patterns.

Fractals are highly significant in many scientific and artistic fields. They are essential to chaos theory, where they appear as geometric depictions of chaotic processes. These often manifest as attractors or as the boundaries between different basins of attraction.

Karperien Strange Attractor 200
Karperien Strange Attractor 200

Beyond pure math, fractal patterns are found in nature, technology, and architecture. They can even describe processes that occur in time rather than just space. From the branching of a tree to the design of complex buildings, fractals provide a mathematical language for the irregular beauty of the world.

FractalTree
FractalTree
649 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (20)
File:sierpinski-carpet.gif
sierpinski-carpet.gif
File:Mandel zoom 14 satellite julia island.jpg
Mandel zoom 14 satellite julia island.jpg
File:Mandel zoom 00 mandelbrot set.jpg
Mandel zoom 00 mandelbrot set.jpg
File:Mandelbrot 12 Encirclements.jpg
Mandelbrot 12 Encirclements.jpg
File:Mandelbrot sequence new.gif
Mandelbrot sequence new.gif
File:Sierpinski carpet 6.svg
Sierpinski carpet 6.svg
File:LineSegment selfSimilar svg.svg
LineSegment selfSimilar svg.svg
File:Simple Fractals.png
Simple Fractals.png
File:FractalTree.gif
FractalTree.gif
File:3D Computer Generated Fractal.png
3D Computer Generated Fractal.png
File:Von Koch curve.gif
Von Koch curve.gif
File:Cantor set in seven iterations.svg
Cantor set in seven iterations.svg

+ 8 more

More to explore

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.