"Androcles" Androcles@ MyPlace.org wrote in message
. uk...

"vector" wrote in message
ups.com...
| how to show that in the direction perpendicular to the relative
| velocity between two reference frames there is no any contraction or
| expansion.noteslease deduce from the two principles of the theroy of
| special relativity.

v = dx/dt
cos(pi/2) = cos(90 degrees) = 0.
cos(pi/2).v = dy/dt = 0.

xi = (x-vt)/sqrt(1- 0.v²/c²) = (x-vt)/1
tau = (t-vx/c²)/sqrt(1-v²/c²)
= (t-v²t/c²)/sqrt(1-v²/c²)
= t(1-v²/c²)/sqrt(1-v²/c²)
= t*sqrt(1-v²/c²)
= t*sqrt(1-0.v²/c²)
= t*sqrt(1)
= t
Einstein did not know the difference between speed and velocity.
Androcles.

You really are an unmitigated idiot. Get a life.