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Comment by EA-3167 | Hacker News Reader

As long as people understand this means perpetual motion which is incapable of doing work is possible, because there's no indication that you can somehow extract anything from this.

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It does make me wonder whether this could help with reversible computing, which reverses out everything except its output, which is all you pay energy for. In theory that would be vastly more efficient.

To my very lay understanding, many quantum phenomena effectively "borrow" energy and then "repay" it. I wonder if one day we might find a way to delay that repayment long enough to accomplish things we otherwise couldn't.

If you are late on your energy loan payments, we will freeze your entire house to 5 Kelvin!

When life freezes your house, make a huge profit from using temperature difference against environment!

It could be fashioned into a neat desk toy though!

If such a toy could be created that displayed a perpetual quantum process, wouldn’t that count as doing work?

If so, then you could only have one that contains an unobservable perpetual quantum process; well, you’d need to trust that the seller that it does!

No, it wouldn’t count: “work” in this context is a technical physics term meaning a force applied over a distance.

If you are not observing some force over some distance then what, exactly, are you observing?

Constant motion doesn't require constant force.

observation requires the transmission of information to the observer, how is it being proposed to do this without force? The question on the table is "constructing a toy which demonstrates" and demonstration requires observation, I think is what is being said

For example, perfectly circular motion against no resistance requires no work since the force is always perpendicular to the motion.

he's saying you can't observe the phenomenon you are talking about without some additional work being done, which you might say is not part of the system, but it is part of the system that G*P proposed

I suspect it should be possible to have something that reflects light without doing work, or at worst absorbs a small portion of the incoming light and reflects the rest. Since it will sit on a desk, it will always be under light when observed by humans.

Brownian motion is perpetual, easily observable by microscope and still it's not doing any work.

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