I created this page and then I realised that there wasn't much to say on the subject! In the old days, people thought that space, in the sense of outside the atmosphere, as being the "Ether". A mythical material which enabled light to propogate, because up to the beginning of the 20th Century, everyone thought light was a wave. And waves (eg, sound, waves in water) require a medium. Dark matter now seems to be the older brother of "the ether". Also unknown and mystical. We talk about the dual form of light (because it is recognised as being both a wave and a particle) and other quantum mysteries on the Quantum Mechanics page (being written).

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