Scientific theory
In 1905, Albert Einstein published the principle of special relativity, which soon became a theory. Special relativity predicted the alignment of the Newtonian principle of Galilean invariance, also termed "Galilean relativity", with the electromagnetic field. By omitting from special relativity the luminiferous aether, Einstein stated that time dilation and length contraction measured in an object in relative motion is inertial—that is, the object exhibits constant velocity, which is speed with direction, when measured by its observer. He thereby duplicated the Lorentz transformation and the Lorentz contraction that had been hypothesized to resolve experimental riddles and inserted into electrodynamic theory as dynamical consequences of the aether's properties. An elegant theory, special relativity yielded its own consequences, such as the equivalence of mass and energy transforming into one another and the resolution of the paradox that an excitation of the electromagnetic field could be viewed in one reference frame as electricity, but in another as magnetism.
Moshe Carmeli
In the 1990s, Carmeli developed a new cosmological theory called cosmological general relativity. He took Einstein's theory of general relativity and extended it into five dimensions, adding the radial velocity of galaxies expanding in the Hubble flow as the fifth dimension. This fifth dimension is known as "space-velocity". He published his initial special relativistic version of the theory in 1997 in his book "Cosmological Special Relativity: The Large-Scale Structure of Space, Time, and Velocity". He then developed the complete general relativistic theory called cosmological general relativity, publishing several papers on its implications over the next decade.