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Q & A: casimir tricks?

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Most recent answer: 07/28/2008
Q:
Hi! I have a question about the Casimir effect. As I understand it, the force is created through the exclusion of low frequency waves inside the space between the plates. At the inside, only the high-frequency waves push against the plates, while at the outside, both high and low frequency waves push against the plates, creating the force. Now, is it possible to use a two-way mirror for one of the plates, which lets high frequency pass at one side, but not from the other? This way, one of the plates feels a greater force and motion ensues. To summarize, the waves pushing against the four sides of the two plates are as follows: Outside of left plate: high and low Inside of left plate: high (low frequencies don't fit) Inside of right plate: none (this is where the two-way mirror effect is applied) Outside of right plate: high and low I wonder if this works. Seems a little too good to be true, though...
- Douwe Kerstens (age 23)
De Bilt, The Netherlands
A:
That's a nice summary of a simple picture of the Casimir effect. However, the sort of mirror you are wondering about (letting light pass only one way) does not exist. It would violate the laws of thermodynamics. So your gut feeling that it's too good to be true is right.

Mike W.

(published on 07/28/2008)

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