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Epicycles Demo
Circles on circles. More epicycles can trace almost any closed path — including a square-ish loop.
Before you start
Circles on circles can trace almost any closed curve. That is why the old model was so flexible — and so suspicious.
Key idea
A model that can draw anything explains nothing until it is forced to make a risky prediction.
What you see
- 1–5 nested circles
- Blue tracer path
Try this
- Set 2 circles, then 4
- Pause and look at the path
Common mistakes
- Equating ‘fits the path’ with ‘is the mechanism’
Glossary
- Fourier intuition
- Sums of circles can approximate other shapes.