This is why scientists still cannot predict the double pendulum exactly.

They used to call me the double pendulum on the dance floor...I don't think it was a complement.

Double pendulum also known as Russian Tecktonik brothers

All I can see is a teenager in the 80s practicing with his nunchucks.

I predict the double pendulum video will run for exactly 1:21 min. What's so hard about that?

I could watch this for a week straight

They might not be able to predict it but they can control it, here's a triple pendulum robot

Here's a bunch of great simulations and visualizations, examining the chaotic (not random!) behavior of the double pendulum.

Anyone else see Bruce Lee with nunchucks?

It was fun from beginning to the end. At some point it looked a stickman dancing

They can't predict it because "all things being equal" was a lie from day one... Which is why I stopped studying physics formally in high school.... And economics in college. Truth was never a part of the equation. They seemed like they were bending the physics to match the story. They were bending the economics to match the story. They were bending the statistics to match the elections. It is tiresome. I think I am just going to start making pool cues and learn to play that table game from India with the floating circular disk. :)

Can they predict a triple pendulum?

never will. just like 3 body problem

I know a guy whose legs move like this when dancing. He should be studied closely

In a normal system (like a single simple pendulum), a tiny 0.1% error in your initial measurement stays small. In a chaotic system like a double pendulum, that 0.1% error doubles repeatedly over time. Within a few swings, the error grows large enough to completely change the path

Sensitive dependence on initial conditions, or, as it is popularly known, chaos theory

Wow watching this explained exactly why

Yup - stock market behaves the same...

Seems deadly 😆

i thought it was bruce lee with a nunchuck

That thing is alive. LMAO

So we can predict the "temperature of earth" in a 100 years at a 10th of a degree, but not this? Seriously? Then science is a scam 😳

@grok is this video genuine?

What keeps it going for so long? Genuine question.

I think it looks predictable. it's obviously a function of initial speed, initial positions, lengths, weights, and frictional forces and the butterfly effect. however an omniscient being would be able to predict it exactly.

I need you to run an errand for me, go tell them to play it on slow motion and calculate.

Nonlinear dynamics

まるでオタ芸だ

@grok please explain

Is it perpetual?

@grok what is the math equation for this?

Well, not with THAT attitude...

The moving pivot is the obvious part. The real reason prediction dies so fast is that the two arms keep kicking each other nonlinearly, so any tiny difference in starting angle or speed grows exponentially. Better measurements stretch how long you stay accurate, they don’t remove the limit. It’s deterministic if you measure properly, but a tiny amount of error in measurement leads to massive results..