That's because it started out that way; when the federal government wasn't involved in those sorts of things and somehow, we never had the in fact, it's talked about--we should-- maybe we'll see it in the next ten or twenty years.

因为从一开始就是分开的,当时的联邦政府还没有介入监管,我们从来没有过...,实际上有一种说法,我们应该,也许10年或20年内,统一监管能够实现

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So, that can be a little bit confusing for us to think about, and when it's a very good question you might, in fact, say well, maybe there's not zero probability here, maybe it's just this teeny, teeny, tiny number, and in fact, sometimes an electron can get through, it's just very low probability so that's why we never really see it.

这想起来有点令人困惑，你们可能会说也许，这里的概率并不是严格的为零，而是非常非常小，所以有时电子就可以穿过去，这是个,很好的想法。

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