To justify the null experiments performed by Michelson and Morley in 1887 to detect the differences of transverse and longitudinal motion of light beams, both H. A. Lorentz (1853-1928 ) and G. F. FitzGerald (1851-1901) independently proposed the space-time contraction (not time dilation) known as the Lorentz-FitzGerald contraction hypothesis of 1892. Thirteen years later, in 1905, Einstein laid down the complete theoretical foundation of both Lorentz-FitzGerald contraction and time dilation with his special theory of relativity, which also predicted the experimental increase of inertial mass where and when it approaches the equivalence of relativistic mass. On the one hand, relativistic mass increase was verified repeatedly by high energy experiments. Its physics is vital to the designs and constructions of both linear and circular accelerators. On the other hand, no experiments have ever provided conclusively the physical validity of Lorentz-FitzGerald contraction hypothesis. One difficulty being the fact that charged particles were practically point-like, zero dimensional objects as observed with respect to the relatively motionless laboratory frame of reference. In spite of the lack of physical evidence for length-space contraction, time dilation was repeatedly verified for the decays of moving elementary particles approaching the speed of light.


Nonetheless, the simultaneous effects of both space contraction and time dilation is sufficient to give the reality of the space-time continuum, which is composed of infinitely many dimensionless points moving at the speed of light around circular paths infinitesimally localized into infinitely many pairs of distinctly linked paths symbolized as the H-pluses and H-minuses of space-time charges as squares of the quantum vacuum fluctuations of zero-point energies. Therefore, space-time charges have zero inertial or rest masses (i.e. independent of Mach’s principle), infinite vacuum energy, and constantly moving at infinitesimally localized uniform circular motions at the speed of light.