Nonlinearity Affects a Pendulum(johndcook.com)
johndcook.com
Nonlinearity Affects a Pendulum
https://www.johndcook.com/blog/2026/04/24/nonlinear-pendulum/
4 comments
Yes. That's what the author means by
> There is a closed-form solution, but only if you extend “closed-form” to mean more than the elementary functions a student would see in a calculus class.
> There is a closed-form solution, but only if you extend “closed-form” to mean more than the elementary functions a student would see in a calculus class.
My bad.
I should have encouraged more curiosity by pointing out that these functions actually have additive as well as multiplicative identities
https://msp.org/pjm/1955/5-2/pjm-v5-n2-p02-p.pdf
(Might even be relevant to the pendulum, see the comment below on the Arithmetic-Geometric Mean ;)
I should have encouraged more curiosity by pointing out that these functions actually have additive as well as multiplicative identities
https://msp.org/pjm/1955/5-2/pjm-v5-n2-p02-p.pdf
(Might even be relevant to the pendulum, see the comment below on the Arithmetic-Geometric Mean ;)
Never saw that AGM expression for K0 before in the earlier linked post. Nor had I heard of the AGM, very cool.
https://cococubed.com/code_pages/pendulum.shtml