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  • One thing that's astounding about Einstein's publications in 1905 is that they spanned

  • such a large breadth of physics: after illuminating the quantum nature of light by explaining

  • the photoelectric effect in March, in April he turned to something apparently more mundane:

  • particles suspended in fluids.

  • In particular, if you look at tiny particles in water, or dust motes in the air, you'll

  • see that they jitter about in a very odd and random way.

  • That is, it appears odd and random unless you believe that the air or water itself is

  • made up of even smaller particles called atoms or molecules, which just bounce off of each

  • other according to very simple rules.

  • This is called Brownian motion, despite the fact that botanist Brown wasn't the first

  • to discover it, and similarly Einstein wan't the first to describe it mathematically

  • but he did draw the conclusion that the mathematical description of Brownian motion is evidence

  • for the existence of atoms even if you can't see them directly, and then he cleverly derived

  • how big atoms should be just based on how much the Brownian particles move.

  • That's like measuring the size of a penguin just by looking at how icebergs jiggle.

  • Talk about cold and calculating!

One thing that's astounding about Einstein's publications in 1905 is that they spanned

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B1 中級

阿爾伯特-愛因斯坦:《原子的大小和存在》。原子的大小和存在 (Albert Einstein: The Size and Existence of Atoms)

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    林宜悉 發佈於 2021 年 01 月 14 日
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