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Mystery #1Tier 3quantum light

Is light a spread-out wave, or a stream of tiny separate bits?

Sunlight streams through your window and lands warm on your hand. Is it a smooth wave, spreading and rippling like the sea? Or is it a hail of tiny separate specks, arriving one by one? So which is it: a spread-out wave, or a stream of tiny bits?

A real double-slit pattern: bright coloured stripes with dark gaps between them, the tell-tale sign of waves adding up and cancelling out
Photo: Aleksandr Berdnikov · CC BY-SA 4.0 · via Wikimedia Commons

Your guess

What do you reckon light really is: a wave, tiny bits, or something else entirely?

There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.

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