Made as a programming challenge but applicable as a learning device, this simulation makes concepts Einstein conceived such as time dilation and length contraction more observable. You can adjust the speed of light, making the effects of relativity more or less obvious by monitoring the length of the spacecraft and the difference between the two stopwatches. Basically, this is what time travel would look like if we could travel at speeds close to that of light, 299,792,458 m/s!
The easiest way to reset is to re-open the file. Make sure you have “python scripts auto-run” enabled in the preferences tab. To observe the effects, make sure k, the effect multiplier, is around 17 (meaning c is 10^17 times slower). Play the animation (Alt-a) and drag around the crosshairs to lead the spaceship around.
https://www.dropbox.com/s/4rvq92kq0ds77py/RelSim.blend
For those interested more interested in the math/science:
This effect occurs because time is a fourth dimension in which you can have a velocity, just like in space. The underlying concept is that the sum of your velocity in space and velocity in time must equal a finite number, which just happens to be c, the speed of light. Hence light has no velocity in time and the highest possible velocity in space. An object with no motion in space has the highest possible velocity in time. This is why time slows down when you move very quickly. A difference in the velocity in time between an object and it’s surroundings equals time travel!