Measured speed versus true speed

摘要

The theoretical predictions, derived from the Lorentz and the Tangherlinitransformations, for the one-way speed of any physical entity are confrontedwith the corresponding expressions for the one-way measured speed obtained froma gedanken experiment. The experiment demonstrates that, for an inertial frame$K'$ in motion relative to an inertial frame $K$ where the one-way speed oflight is isotropic, even the special theory of relativity renders the one-wayspeed of light as function of the velocity of $K'$ in agreement with theTangherlini transformations. However, the two-way speed of light remainsconstant for all inertial frames, in agreement with the two-way experimentaltechniques. This implies that there must exist \emph{one and only one} inertialframe where the one-way speed of light is isotropic. These investigations alsoshow how we can determine, with certain restrictions, the true speed of aphysical entity and of the true speed of $K'$ relative to $K$.