万物简史(MP3+中英字幕) 第206期:威力巨大的原子(20)
日期:2017-02-06 18:06

(单词翻译:单击)

What this means in practice is that you can never predict where an electron will be at any given moment. You can only list its probability of being there. In a sense, as Dennis Overbye has put it, an electron doesn’t exist until it is observed. Or, put slightly differently, until it is observed an electron must be regarded as being “at once everywhere and nowhere.”
真正的意思是,你永远也无法预测电子在任何特定时刻的位置。你只能认为它有可能在那里。在某种意义上,正如丹尼斯·奥弗比所说,电子只有等到被观察到了,你才能说它确实存在。换句稍稍不同的话来说,在电子被观察到之前,你非得认为电子"哪里都有,而又哪里都没有"。
If this seems confusing, you may take some comfort in knowing that it was confusing to physicists, too. Overbye notes: “Bohr once commented that a person who wasn’t outraged on first hearing about quantum theory didn’t understand what had been said.” Heisenberg, when asked how one could envision an atom, replied: “Don’t try.”
如果你觉得被这种说法弄得稀里糊涂,你要知道,它也把物理学家们弄得稀里糊涂,这是值得安慰的。奥弗比说:"有一次,玻尔说,要是谁第一次听说量子理论时没有发火,这说明他没有理解意思。"当有人问海森伯是不是可以想像一下原子的模样,他回答说:"别这么干。"
蓝色的原子辐射背景

So the atom turned out to be quite unlike the image that most people had created. The electron doesn’t fly around the nucleus like a planet around its sun, but instead takes on the more amorphous aspect of a cloud. The “shell” of an atom isn’t some hard shiny casing, as illustrations sometimes encourage us to suppose, but simply the outermost of these fuzzy electron clouds. The cloud itself is essentially just a zone of statistical probability marking the area beyond which the electron only very seldom strays. Thus an atom, if you could see it, would look more like a very fuzzy tennis ball than a hard-edged metallic sphere (but not much like either or, indeed, like anything you’ve ever seen; we are, after all, dealing here with a world very different from the one we see around us).
因此,结果证明,原子不完全是大多数人创造的那个模样。电子并不像行星绕着太阳转动那样在绕着原子核飞速转动,而更像是一朵没有固定形状的云。原子的"壳"并不是某种坚硬而光滑的外皮,就像许多插图有时候怂恿我们去想像的那样,而只是这种绒毛状的电子云的最外层。实质上,云团本身只是个统计概率的地带,表示电子只是在极少的情况下才越过这个范围。因此,要是你弄得明白的话,原子更像是个毛茸茸的网球,而不大像个外缘坚硬的金属球。(其实,二者都不大像,换句话说,不大像你见过的任何东西。毕竟,我们在这里讨论的世界,跟我们身边的世界是非常不同的。)

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