Ether theories

On Saturday we talked about including some definitions of ether in the newsletter that we’re making. As a concept that some of us have found challenging since Geoff’s radio workshop we thought we might have a look at how the meaning of the word ether has changed – possibly by constructing a timeline of definitions. I actually found this on Wikipedia but it would be nice to put together a few concise definitions, maybe including some of our own. The following are taken from books that I had at home but they were all written relatively recently so are quite consistent – if anyone can find a much older definition to compare, that would be great.

ether clear sky, upper air. (The Little Oxford Dictionary, 1994)

ether n. Clear sky, upper air; medium formerly assumed to permeate space and transmit electromagnetic radiation; ethereal a. light, airy, of unearthly delicacy of substance etc., heavenly (The Oxford Handy Dictionary, 1978)

ether, a hypothetical substance formerly supposed to pervade the whole of space and be the medium in which light travelled. The Michelson-Morley experiment, which used interferometry to detect the presence of this luminiferous ether and to measure the movement of the Earth with respect to the ether, has led to the abandonment of this hypothesis and the acceptance that electromagnetic radiation is a wave motion without a medium. (Oxford Illustrated Encyclopedia of the Universe, 1992)

Michelson-Morley experiment An experiment performed by A.A. Michelson and E.W. Morley in 1881 in an attempt to demonstrate the existence of the luminiferous ether by measuring the earth’s velocity relative to it. They used a Michelson interferometer to obtain interference fringes and then rotated the apparatus through 90 degrees expecting to find a shift in the fringes, since the velocity of light would be different in the two directions. This difference would result from the earth’s motion through the ether. However, no shift was detected. This negative result led to the downfall of the ether theory  and was explained by Einstein’s theory of relativity in 1905. (The Macmillan Encyclopedia,1988)

Michelson, Albert Abraham (1852-1931) American physicist, of German extraction, who is mainly remembered for his work on the velocity of light. Using his interferometer (invented in 1881), he and Edward W. Morley showed in 1887 that the speed of light in a vacuum is the same in all inertial reference systems (coordinate systems moving at constant velocity relative to each  other). It had been held since the days of Huygens that light travels through a stationary substance filling the whole of space (the so-called ether), but Michelson and Morley’s experiments proved that there was no such thing. This led directly to the development of the special relativity theory by Lorentz and Einstein. (Who Did What, 1974)




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6 Responses to Ether theories

  1. Simon says:

    Ahh, love it. Will put the top three in now for an overall definition and then can add the others in future editions. Really like the line ‘ light, airy, of unearthly delicacy of substance’, it sounds lovely.

  2. Polly says:

    Yeah I don’t know why but I hadn’t thought of the word ethereal being related to ether..

  3. Kate says:

    Guys this is great. Nice post Polly. In particular how you discuss the possibility of creating a timeline of meaning.

  4. Sarah Browne says:

    Great post Polly – I think how rigorous you’ve been about quoting your sources really helps to highlight the specificity of the definition and how it seems to have shifted over time, moving between poetry and science, and the field of science was itself changing. I was interested to see what an impact Geoff’s discussion of the ‘ether’ had on the group too, I didn’t realise that! I like it as a thematic or title for your publication, because it emphasises plural ways of understanding one idea. I think it’s important that whatever you decide to call your publication, it can allow for different voices within it.

    The book I mentioned in relation to the history of pirate radio is ‘Death of a Pirate: British Radio and the Making of the Information Age’ by Adrian Johns, 2011. Some extracts about what in the early 1920s the BBC called ‘ether chaos’ (what we would now call interference):

    ‘In the United States, the proliferation of stations in competition with each other was already leading to severe mutual interference in major cities. With several transmitters all seeking to dominate the one permitted wavelength, the prospect was of a mutually destructive “ether chaos”. That prospect haunted officials in London, who were acutely conscious that the country was far smaller and more densely populated than the United States. In common with their American counterparts, they believed chaos to be a danger implicit in the physics of the ether itself. Two principles, then, were axiomatic for the coming British broadcasting regime: that the state must forestall chaotic interference by restricting the number of broadcasters, ideally to one; and that that broadcaster must be neither crassly commercial nor overtly controlled by the state. In both respects the hallowed openness and democracy of the medium would become central issues.’ (p18)

    ‘Ports and electricity supply shared the same characteristics as radio: they centred on a shared resource, and were seemingly poor candidates for either unregulated laissez faire [capitalism] or full state control. The founding of the BBC was therefore a response not just to ether chaos but to economic chaos.’ (p32)

  5. Natasha says:

    I managed to find some fairly old dictionaries around the house and this is how ‘ether’ was defined:

    - “intangible fluid formerly supposed to fill all space; the clear sky, region above clouds.” (Collins English Gem Dictionary, 1972)
    - “hypothetical medium supposed to fill all space and support the propagation of electromagnetic radiation; upper air, clear sky.” (The Penguin English Dictionary, 1969)
    - “a hypothetical, all-pervading fluid which serves to transmit heat and light waves.” (Words – The New Illustrated Dictionary, 1956)

    I also found this etymological dictionary online and it had a relevant description which also states how the word ether dates back. I think the last part is particularly interesting… (

    - “late 14c., “upper regions of space,” from O.Fr. ether and directly from L. aether “the upper pure, bright air,” from Gk. aither “upper air; bright, purer air; the sky,” from aithein “to burn, shine,” from PIE root *aidh- “to burn” (see edifice).
    In ancient cosmology, the element that filled all space beyond the sphere of the moon, constituting the substance of the stars and planets. Conceived of as a purer form of fire or air, or as a fifth element. From 17c.-19c., it was the scientific word for an assumed “frame of reference” for forces in the universe, perhaps without material properties. The concept was shaken by the Michelson-Morley experiment (1887) and discarded after the Theory of Relativity won acceptance, but before it went it gave rise to the colloquial use of ether for “the radio” (1899).”

  6. annabel says:

    Just thought I’d add the oed (Oxford English Dictionary) online as a good place to look for definitions and any kind of linguistics research. There are examples of ether being used in 1398 onwards.
    To log on you need a library card. (most libraries subscribe but I’m not if all do)
    Link to sign up to Birmingham libraries : (no need for proof of address! :) )