Time dilation... This concept established in 1905, appeared in a Paper named "special relativity" . Done by the gentlemen EINSTEIN and LORENTZ, this theory was written to unify electromagnetics area and Newtonian mechanics . Einstein subsequently replaced this work by the "General Relativity," to explain universal gravitation. Our first book dedicated to the resolution of the partials differentials equations ("Gradient of time and Partials Differentials...