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by lukan 371 days ago
"If you shine a laser into a box with one-way mirrors on the inside, will it reflect forever?"

No, because each reflection comes at a cost (some light transformed to heat)

"Why do people mainly marry and make friends with people who look extraordinarily similar to themselves?"

To not get so much surprises and have a more stable life. (I didn't choose that path.)

(But I feel it would be too much OT answering the other questions and don't want to distract from this great submission or the interesting Wasmi concept)
1 comments
9d 371 days ago
No, I do not accept this. There must be a way. What if the mirror box has a high enough heat? Would it work then? The box could be made of a heat resistant material, like fiberglass.
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Bjartr 371 days ago
It's not that the mirror or box is damaged by heat, it's that each bit of heat energy comes from a bit of light energy. Eventually the light bounces enough times that there's no energy left in it.
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9d 371 days ago
I understand, but what I mean is, what if there is no more opportunity for the light to emit heat, because the surrounding environment is already saturated with so much heat that it can't accept more? Is this a possible way to prevent the light from emitting heat and therefore prevent the light from decreasing its luminousness? There must be a way!
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Bjartr 370 days ago
Why must there be a way?

A few notes: * There's no such thing as "absolute hot" state that meansno more heat can be added * Blackbody radiation means that above a certain temperature, regardless of what you make your mirror out of, it will be spontaneously emitting visible light at all times.

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lukan 370 days ago
Indeed. There is only an absolute zero, that cannot get colder, but more heat is always possible as more heat means more rapid movement of elements. While absolute zero at 0 K means no movement.
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lukan 371 days ago
Are you aware of that old concept and why it doesn't work?

https://de.wikipedia.org/wiki/Perpetuum_mobile

Same principle.

Basically, what you propose negates the nature of reality. There is always friction/energy loss into heat (increased chaotic movement). Only way to deal with it, if you want permanent cycles, is constantly add energy in the same amount that is lost.

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