The Luminiferous Ether Was Disproved in 1887
Ether is an anaesthetic chemical and a name for the upper air. Physics once proposed an ether filling space, and an experiment ruled it out.
Ether is a volatile liquid once used as an anaesthetic, and an old name for the upper air. Nineteenth-century physics also proposed a *luminiferous ether* filling all space, on the reasoning that light waves must travel through something. The Michelson-Morley experiment of 1887 looked for it and found nothing, and that null result helped clear the way for Einstein's special relativity. In Greek myth, *aither* was the pure air the gods breathed.
- An anaesthetic liquid. *Ether was used in surgery.*
- The upper air. *The clear ether.*
- A hypothetical medium. *The luminiferous ether.*
- Ethereal — delicate and unearthly. *An ethereal voice.*
- Greek — *aither*, the upper air. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | ether | Diethyl ether. |
| Adjective | ethereal | Ethereal beauty. |
| Alt spelling | aether | The aether. |
| Greek | aither | Upper air. |
| Related | ethereally | Ethereally pale. |
- Ether was first used as an anaesthetic in 1846.Medicine.
- The Michelson-Morley experiment found no ether.Physics.
- She has an ethereal quality.Adjective.
Why the ether was proposed
- Waves need a medium — sound needs air, water waves need water
- Light was known to be a wave, so physicists assumed a medium
- The ether was to be everywhere, weightless and undetectable
- Michelson and Morley, 1887 — measured light in two directions and found no difference
- Einstein, 1905 — special relativity made the ether unnecessary
Latin *aether*, from Greek *aither*, the upper pure air, from *aithein*, to burn or shine.
Does the luminiferous ether exist?
No. The Michelson-Morley experiment of 1887 found no evidence for it, and special relativity made it unnecessary.
Is ether still used as an anaesthetic?
Rarely. It is flammable and causes nausea, so safer agents replaced it in most countries.