Bort - 2017-04-17
I think the same effect can be seen with books too. Take a normal rectangle-shaped book. There are three basic axes of rotation: the one that goes top to bottom, the one that goes left to right, and the one that goes front to back. If you toss the book in the air and spin it along the top-to-bottom or front-to-back axes, it wobbles in the air a tiny bit; but if you try to spin it along the left-to-right axis, it's going to spin all unpredictably.
It's been 30 years since I did the math on this, but the basic deal is, on the largest and smallest moments of inertia*, any small motion on the other axes results in a sine-wave wobble; while on the middle moment of inertia*, those small motions throw the whole system increasingly out of whack.
*: Moment of inertia: think of it like the cross-section as the book rotates. Like for the left-to-right axis, look at the spine of the book. You get the smallest cross section with the top-to-bottom axis -- look down at the top surface of the book -- while you get the biggest cross section with the front-to-back axis, looking at the front of the book like a normal person.
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Mr. Purple Cat Esq. - 2017-04-17 You may find this interesting
https://mathoverflow.net/questions/81960/the-dzhanibekov-effec t-an-exercise-in-mechanics-or-fiction-explain-mathemat
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Oscar Wildcat - 2017-04-17 Depends what the book said, but about the general idea, quite serious. The system most studied is a drop being bounced above a liquid surface. The resulting wave/particle interacts with other drops and the environment just as individual quanta do. It's a physical analog to the De Broglie pilot wave.
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Oscar Wildcat - 2017-04-18 Yes, well that is crazy nonsense, of which there is no end of.
Here is what I am talking about. Pilot waves for dummies.
https://www.youtube.com/watch?v=WIyTZDHuarQ
For the more erudite.
https://youtu.be/nmC0ygr08tE
http://math.mit.edu/~bush/wordpress/wp-content/uploads/2013/10 /Gallery-Harris-2013.pdf
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