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Comment: Re:Once again Correlation != Causation (Score 3, Informative) 291

Studies don't prove things. Studies fail to disprove things. Correlation doesn't imply causation, but it certainly is consistent with a theory of causation. It's also consistent with the theory that the purported effect is actually the cause, and the cause is the effect.

Comment: Re:It works both ways (Score 3, Insightful) 886

by Khashishi (#49342093) Attached to: Gen Con Threatens To Leave Indianapolis Over Religious Freedom Bill

Because history shows us that it turns out bad. When bigots are a small minority, it's ok to let the free market deal with the problem. When they are in the majority, or when they wield a majority of the power, the free market gets ugly. Just look at pre-civil rights era segregation.

Comment: translation (Score 1) 83

This experiment measures the power level where spontaneous emission becomes comparable to stimulated emission.

You have a similar situation in a laser. A laser works on the principle of stimulated emission. When you pass laser light of an appropriate frequency through an excited laser cavity, the light is amplified, since the light stimulates nearby particles to emit more light. So the light grows exponentially with the length of some cavity until saturating (by fully de-exciting the cavity). But, where does the initial "seed" light come from in a laser? The laser cavity also emits light via spontaneous emission. So what you have is some combination of spontaneous and stimulated emission. The stimulated emission ramps up exponentially and dwarfs the spontaneous emission, which is always present.

Stimulated emission can be treated using classical mechanics by treating the medium as an amplifier. But spontaneous emission must be treated quantum mechanically. Of course, stimulated emission can also be treated with quantum mechanics. So quantum mechanics is valid all the time, but classical mechanics is only valid above a certain point.

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