https://mathoverflow.net/a/156407
(updated link to original, not the repost)
A lot of times with math I don't think the word "why" should be used. Those blocks computing pi was a good example where they "proved that they compute pi", but not really why. What is the real distinction I'm trying to make here and how to explain it?
https://easylang.online/show/#cod=jVPbbptAEH3frzhSpMqJFYppI0...
If you hold 2 balls up, and let them fall, 2 balls swing up on the other side. How does it know how many you swung??? It boggled my mind for the longest time. Then I got to playing with one, and found something interesting. It doesn't always seem to work!
If the balls are perfectly aligned, and touching each other, the effect is dampened by the multi-body collision. It's strongest when the balls are just barely not touching.
What we see as multiple balls swinging and hitting is really a whole bunch of individual 2 body collisions that are close enough in time to seem like they are a single event.
I could be wrong about the reason, but this was my observation.
Edit: You’re reading his notes/summary of the topic. Basically what he’s understood so far. “Expository webpages - For my own future reference. Intended audience is myself.”, see https://vanhunteradams.com/#Expository-webpages
(Just joking).
Dealing with friction complicates matters significantly. At the very least you can't expect the collision to be elastic.
