Relativity is a hard concept to grasp. So to make it easier to understand, researchers from the Massachusetts Institute of Technology's Game Lab
decided to turn it into a game. The developed "A Slower Speed of
Light." The game itself is really
simple: run around a landscape and collect multicolored orbs until you acquire 100 of them.
But it's the world of the game that gets interesting: as you
collect more orbs, the speed of light slows down. The player sees more extreme effects of this as she walks around.
What are some of these effects? For one thing, you'd be able to see
beyond visible light into the infrared and ultraviolet spectrum. This
is because as an observer moves forward, the light waves she sees coming
toward her from other objects get compressed — they get shorter.
Anything producing infrared light will become visible. Eventually it
would possible to see radio waves.
Meanwhile, the light waves from any objects she is passing by will
stretch out, making the objects look redder. As she looks behind her,
the visible light will all eventually move to the infrared. Eventually,
even gamma and X-rays would become visible. The phenomenon is known as the Doppler
Another consequence of relativity is concentrating the light
from objects in front of you — and to the sides. It's called relativistic
aberration. Objects on either side start to enter the field of view in the
front, and the world starts to look like it does through a fish-eye lens. It
also means anything in front of you looks brighter. Move backwards, and the
world seems to go darker as the light waves you can see come from a narrower
and narrower field.
The game also adds in time dilation and altering the length
of space dimensions in the direction of motion. As one approaches the speed of
light, time slows down –- the observer's clock moves more slowly than a stationary one. This is the source of the "twin paradox" in which one
twin who travels near the speed of light for years ages more slowly than her
sister on Earth, though the slowly aging twin doesn't notice until she returns to her now-older sisiter. (It's also a common plot device in science fiction novels,
notably Joe Haldeman's The Forever War).
Less well-known is the shortening of length dimensions -– a
moving object looks shorter in its direction of motion, so a person running by
at near light speed would look as though they had been flattened to an outside
observer. The runner wouldn't see any difference.
The result is a world where everything bends and other
objects seem to slow down, and it becomes difficult not to overshoot targets.
The game might be too simple for some people but it doesn't
have to stay that way: the code is open source, so anyone who wants to design a
game in the world governed by relativity will be able to do so.
Photo: The world at about 25 percent lightspeed. Credit: MIT Game Lab