Adding Velocities, Relativistically

I note that C is described as being the maximum possible speed/velocity. If speed is the rate of change of position, isn't then the maximum possible speed 2C? Turn on a light bulb (in a vacuum). Instanteously a wave front (photons) are moving in direction x at a velocity of C relative to the bulb, or the original position. Also instantaneously, another wave front (photons)are moving in the opposite direction at a velocity of C. Photons in the moving in the original direction are moving at a velocity of 2C RELATIVE to the photons moving in the second direction x - 180degrees.
- Guy Eltringham (age 66)
Los Angeles California USA

We recently answered a similar question about that, although it had to do with space ships and not light beams. Type the number 15917 in the search box.  Give it a look and if you still have questions let us know. 

LeeH

(published on 08/19/2010)