Quantum Consepts - that can be wrong-but Usually ain't

  The Lewis Ratchet Revisited: Two Perspectives, One Principle https://www.youtube.com/watch?v=OxHIMhTpFYU When we first imagine the Lewis Ratchet —the idea that you can move a platform by throwing and retrieving a mass inside it—it’s often easiest to picture a raft on water. You throw a medicine ball forward (the “kick”), then gently walk it back (the “reset”), and thanks to friction or drag, the raft creeps ahead a little more each cycle. That initial, Huck Finn–style image might suggest that friction is absolutely essential. After all, friction is what lets you walk without slipping and prevents the raft from drifting back during the slow reset. But in a more general, frictionless environment—say, a sealed box floating in the vacuum of space—the same fundamental process happens via normal forces , collisions , and hooks or latches that allow internal masses to push off the box’s walls. This is an example of the idea.  The Vpython Script launches 4 masses and then the Spac...

  The Lewis Ratchet: Forward Asymmetric Momentum Transfer I figured out how to make a model of this:  https://www.youtube.com/watch?v=A5x0Yd7kjSc Imagine you’re floating on a small raft in a calm lake—a bit like Huck Finn’s raft, but with a twist. Instead of a motor or engine, your raft relies on an ingenious idea: by moving an internal mass back and forth in an asymmetric way, you can slowly “scooch” the raft forward. This is the essence of the Lewis Ratchet. The Basic Idea In an ideal, frictionless world, any internal motion—like shaking a heavy bar or throwing a medicine ball—cancels out. When you push one way, you push the other equally. But if you can arrange for the forward push to be strong and quick, and the return motion to be gentle and slow, the momentum transferred during the fast “kick” isn’t completely undone by the slow “reset.” In a real-world setting, friction (or water drag) then “locks in” that net gain, causing the raft to move forward incrementally with ea...