- #26

- 991

- 1

**superluminal non physical motion**

The question is not looking for the speed at which light spreads from a flash point; this is what's confusing about the question. [tex]F = \left( t, \frac{c^2}{v} t, B, C \right) \right}.[/tex]

Now, consider two times, [itex]t_1[/itex] and [itex]t_2[/itex], for S, with [itex]t_1 < t_2.[/itex] At time [itex]t_1[/itex], a bunch of flashes go off simultaneously in the spatial plane [itex]x = c^2/v t_1;[/itex] at time [itex]t_2[/itex], a bunch of flashes go off simultaneously in the spatial plane [itex]x = c^2/v t_2.[/itex] The spatial distance between the planes divided by difference in times gives that the "plane of flashes" propagates with speed [itex]c^2/v.[/itex]

*The speed cc/V is superluminal but the supposed motion is not physical. A Lorentz transformation relates the spece-time coordinates of two events which take place at the same point in space and performing it the point in space does not move!*

Regards