Science and Politics of the Aether
19th century physicists had always assumed that waves need a medium to propagate in; water waves move in water; sound waves move in air. The discovery of light waves resulted in a postulated medium, the aether, in space to allow light transmission. Most college physics students know of Albert Michaelson and Edward Morley’s famous interferometer experiment to try to detect this medium.
As Richard Milton notes, every
high school physics student has taken down the same notes for more than a
century describing the results of that experiment: If the aether
exists there should be a minute – but measurable – drag effect on a beam of
light that will delay it and show up as ‘interference fringes’ in the interferometer.
The experiment shows a 'null result' -- no matter how the interferometer is
orientated with respect to the earth's movement, there is no measurable aether drag.
The experiments of Michelson, Morley and of Dayton Miller have been repeated and analyzed in modern times by French engineer Maurice Allais, awarded the Nobel Prize for Economic Science in 1988, and he is largely responsible for bringing Miller's discoveries to a modern audience.
National Adcademy of Sciences Biographical Memoir of Dayton Clarence Miller
states: "The famous Michelson-morley experiment which was designed to
measure the velocity of the earth through ether and which laid the experimental
foundation for the theory of relativity was performed in 1887 at Case School.
The Millers and the Morleys became warm friends...in 1900 they went to
Einstein’s Theory of Relativity was gaining in vogue, and the status of Miller’s successor as the Physics Department Chair soared after  attacking Miller’s work, after his death, as worthless. This was done not as the result of a critical review and re-analysis, but as a “trawl” through the data looking for possible errors. Dr. James De Meo noted: “'This kind of chronic misrepresentation of the slight positive results of many interferometer experimenters, including Michelson-Morley, Morley-Miller, Sagnac, Michelson-Gale, and Michelson-Pease-Pearson, suggests an extreme bias and deliberate misrepresentation.”
On the other hand, some modern analysis appears to have shown that both the Michaelson Morley, as well as the Miller studies, were in error, primarily because neither of the studies analyzed the variation in systematic error, which in modern reconstruction made all there results statistically insignificant. Miller in particular was apparently unknowingly looking at insignificant patterns in the systematic error that mimicked the appearance of a real signal. 
As far as orthodox science is concerned today, special and general relativity have held their ground and are universally accepted. Physicists ask: if light is propagated as a wave in the aether, how does quantization of light and absorption spectra occur? On this basis, the aether appears to be dead and buried. 
Interestingly however, Glenn Starkman, ironically from Case
colleagues Tom Zlosnik and Pedro Ferreira of the University of Oxford are now
resurrecting the aether concept in a new form in an
attempt to solve the puzzle of dark matter, the mysterious substance that was
proposed to explain why galaxies seem to contain much more mass than can be
accounted for by visible matter. They posit an ether
that is a field, rather than a substance, and which pervades space-time.
"If you removed everything else in the universe, the ether would still be
there," says Zlosnik.
This ether field … is something that boosts the gravitational pull of stars and galaxies, making them seem heavier, says Starkman. It does this by increasing the flexibility of space-time itself. "Interestingly, this controversial aspect should make it easy to test for experimentally," according to New Scientist magazine: Sending sensitive clocks into space may be all that's needed to test for the ether's existence. 
 Richard Milton: Michelson-Morley & the Story of the Aether Theory www.cellularuniverse.org/AA2MM_Aether.htm
 books.nap.edu/html/biomems/dmiller.pdf p. 63
 Special Relativity, the Lumeniferous Aether, and Experiments 4/27/2006 http://www.iit.edu/~robertst/Colloquium_Apr_27.ppt
Tick-tock test : New Scientist magazine, 25 August 2006, page 8-9