Science & TechFact

Jittering pollen proved that atoms exist.

In 1827 the botanist Robert Brown watched pollen particles twitch in water under his microscope, with nothing alive involved. In 1905 Einstein explained the jitter: invisible water molecules keep bumping the grains. Jean Perrin measured it in 1908, and the debate over whether atoms are real was over. Nobel Prize in 1926.

Useful: Dust dancing in a sunbeam is being shoved around by air molecules in the same way.

Source: en.wikipedia.org

AtomeGeschichte Physik

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