Science and Technology of the Casimir Effect | Hacker News Reader

Science and Technology of the Casimir Effect

physicstoday.scitation.org

43 pointsyummypaint8 comments

Decades ago, i invented a perpetual motion machine based on the Casimir effect.

You have this setup with two plates or whatever, with the distance between them suitable for the Casimir effect to arise, pulling the plates together. One of the plates is movable, and you have a mechanism for extracting work when the force pulls the plate inward, and for moving the plate back out - maybe the plate is on a string attached to a motor-generator, or to a magnet moving in a coil or something.

The trick is that you make one of the plates out of a semiconductor. The Casimir effect only arises between conducting plates. So you can turn the effect on and off using a voltage on the semiconducting plate.

So, you can apply a voltage to turn the effect on, let the moving plate move inwards, extracting work as it does so, then withdraw the voltage to turn the effect off, move the plate outwards, this time not needing to do work against the force, then repeat the cycle.

Obviously, this won't work. Mostly it won't work for engineering reasons involved in the scale of the thing. But there must also be a reason why it wouldn't work in principle. I don't know what that reason is.

It's still so weird to me that stuff appears and disappears out of nothing. But experiments show it's really happening. The universe continues to surprise me.

"Nothing" is a colloquial stand-in for "things that don't readily react to sensory machines that we have access to". There's a lot of something in that nothing, otherwise nothing would be happening.

This is not the first time I've felt compelled to quote from Through the Looking Glass: -------- [the White king said:] ‘Just look along the road, and tell me if you can see either of them.’

‘I see nobody on the road,’ said Alice.

‘I only wish I had such eyes,’ the King remarked in a fretful tone. ‘To be able to see Nobody! And at that distance, too! Why, it’s as much as I can do to see real people, by this light!’

That is not true. Casimir force is due to EM interaction between the objects (retarded London forces). EM field is not "nothing", it is a thing that is everywhere and has properties.

Thanks for this. I was under the impression there was some difference between relativistic electron-electron dispersion and the Casimir force - after reading your comment I googled some recent papers and convinced myself.

My first thought after knowing this was that maybe micro/nano-fabrication won't be as kneecapped by this force as I thought - as it is not an intrinsic/unavoidable property of the vacuum, but a tune-able property of the materials.

> That is not true ... EM field is not "nothing", it is a thing that is everywhere and has properties.

I feel that slightly trivializes the unknowns of what fields actually are and is a bit pedantic in the context of the comment you replied to.

If fields are not nothing, okay, point to one. Show me it. Yes, they are a thing in the sense that we can measure their effect on other things that we can see and point to, but I think it's a huge rabbit hole to try to answer just what fields are. In many respects, fields are just a mathematical model of effects we see.

You are reading too much into my comment. I only asserted there is no need for "magical explanations". Of course fields are not a trivial idea.

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