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From: moroney@world.std.spaamtrap.com (Michael Moroney)
Newsgroups: sci.physics
Subject: Re: Gyroscopic matter and light
Date: Sun, 8 Jul 2018 16:40:25 +0000 (UTC)
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john <johnsefton288@gmail.com> writes:

>Odd
>"That is sinusoidal motion.  No rotation. "
>Oh, but the spring is twisting back and forth.

What twisting? Good grief.

Maybe certain real-life non-ideal coil springs may twist but the spring
equation applies anywhere where the ODE is the behavior, such as rubber
or steel rods. No twisting in y" + ky = 0, it's one dimensional.