Double Pendulums are Chaoticn't
2swapCited 3× on HN, 2025–2026
explainer · general · evergreen · 2025–2026 on HN
A short explainer from 2swap on the chaotic behavior of double pendulums. It examines how predictable the system is for some starting conditions and whether closed-form solutions exist.
Cited as a related video when threads touch on chaos, predictability and fractals from pendulum state spaces.
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3 comments from Hacker News
Correct, it's akin to chaos theory or the butterfly effect, which, even it can be predictable for many ranges of input: ▶ this video
As an aside, here's a relevant video about the (sometimes not) chaotic nature of double pendulums: ▶ this video
You can make a fractal out of the state graph of a double pendulum: ▶ this video I don't doubt there could be an iterative formula that maps to it, but I'd be very surprised.