No matter how I look at this issue, I cannot escape being troubled by the fact that we have in place a policy which forces young men and women to lie about who they are in order to defend their fellow citizens."

VOA: special.2010.02.06

So we can see if we look at the probability density plot, we can see there's a place where the probability density of is actually going to be zero.

就能看到,有些地方，找到一个电子的,概率密度,我们可以考虑。

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