Professor Ad Lagendijk received the Spinoza Prize of 2002 for his research on the propagation of light in strongly scattering media, a field that according to the jury, he defined himself and brought to maturity both experimentally and theoretically through his research.
42.
This historic null result, as scientists call it, was proof that ether, as it was then imagined, does not exist and that Einstein's special theory of relativity, which offers an alternative explanation for the propagation of light, is correct.
43.
The predictions of Ritz's version of emission theory were consistent with almost all terrestrial interferometric tests save those involving the propagation of light in moving media, and Ritz did not consider the difficulties presented by tests such as the Fizeau experiment to be insurmountable.
44.
A priori, it is not clear whether the new local frames in free fall coincide with the reference frames in which the laws of special relativity hold that theory is based on the propagation of light, and thus on electromagnetism, which could have a different set of preferred frames.
45.
From the point of view of classical physics as being non-relativistic physics, the predictions of general and special relativity are significantly different than those of classical theories, particularly concerning the passage of time, the geometry of space, the motion of bodies in free fall, and the propagation of light.
46.
According to the general theory of relativity space without Aether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time ( measuring-rods and clocks ), nor therefore any space-time intervals in the physical sense.
47.
But the same was not supposed to be true for light, since Maxwell's mathematics demanded a single universal speed for the propagation of light, based, not on local conditions, but on two measured properties, the permittivity and permeability of free space, that were assumed to be the same throughout the universe.
48.
In the 19th century most physicists believed, incorrectly, that all of space was filled with a medium called the " Luminiferous aether " ( or " ether " ), a hypothetical substance which was thought necessary for the transmission of electromagnetic waves and to the propagation of light, which was believed to be impossible in " empty " space.
49.
This does not change the absolute value of " c ", nor is it completely new : any medium other than vacuum, such as water or glass, also slows down the propagation of light to " c " / " n " where " n " is the material's refractive index.
50.
In general, magneto-optic effects break time reversal symmetry locally ( i . e . when only the propagation of light, and not the source of the magnetic field, is considered ) as well as Lorentz reciprocity, which is a necessary condition to construct devices such as optical isolators ( through which light passes in one direction but not the other ).
