8
Let us now have a look at the speed of light.
 The red dot on the Spacetime map is a traveling photon (interpret it as an electromagnetic 'lightbullit'). The speed of light is about 300.000 km/sec (299792458 m/sec). That's very fast: 7,5 times around the world in one second! (My sketches are not to scale to keep it visually more attractive.) The distance between the car and the photon is not the same as the distance between the motorcycle and the photon: the speed of the photon is not the same for ('relative to') me in the car and for (relative to) the biker on his motorcycle. Unfortunately, this does not reflect what reality tells us: speed of light is ALWAYS the same. Relative to me (the car) AND relative to the motorcycle! Relative to everything and everybody! This is not a matter of believing or not, it is a simple fact that can be measured, and has been measured over a thousand times. Fact is: our spacetime map is wrong! 

=> Go to ....
 Introduction
 Relativity for Dummies
 4D Spacetime Block Universe
 Reciprocal time dilation
 Reciprocal length contraction
 Lengths do not 'appear' contracted!
 Measuring the contracted train
 Constant light speed
 Where is the bullet?
 Train experiment
 Slower and shorter  case study
 Minkowski vs Loedel
 Spacetime video
 Further reading