Special relativity (alternative formulations)
Hendrik Lorentz and Henri Poincaré developed their version of special relativity in a series of papers from about 1900 to 1905. They used Maxwell's equations and the principle of relativity to deduce a theory that is mathematically equivalent to the theory later developed by Einstein.
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.