The speed of light, nearly 300 000 km/s or just over
one billion km/h is very much larger than any speed that
we know from everyday life.
But the speed of light is not merely a high velocity.
The special theory of relativity, formulated by Albert Einstein
in 1905, describes it as a limiting velocity:
The speed of light is the cosmic speed limit that no material
object can reach or exceed. At velocities close to this
speed limit, relativistic effects are important that
are unmeasurably small at everyday velocities.
In the computer simulation we can "experience" high speed motion.
We observe objects that move by at nearly the speed of light.
Or from the other point of view: We travel at nearly the speed
of light and take a look-around.
Ultimately, these two points of view are equivalent. We may
consider the observer to be moving or the object, the resulting
movie is the same (principle of relativity).
The explanations, however, are different for the two different
points of view. For this reason, and also because it simply
is more natural to consider houses as stationary and
bikers as moving than the other way around, we discuss
both points of view.
Part I: The visual appearance of fast moving objects
In the main article
Motion near the cosmic speed limit
we observe various objects in motion at nearly the speed of light.
We find, e. g., that moving rulers may sometimes look contracted,
but mostly do not. Or, the side of a cube that is facing us
and is unobstructed is not necessarily visible. These findings are effects of
finite light travel times and are explained by animations.
Other topics are the changes in apparent colour due to fast motion
and real observations of high-speed motion in space.
The complexities of relativistic soccer are discussed in
The ball is round..
Also features a movie on what a high-speed football would look like
according to pre-Einstein physics. Animations explain the consequences
of finite light travel times.
Sights that Einstein could not yet see
shows more simulations of objects moving at nearly the speed of
light. The most important effects (apparent change in length, apparent
rotation and distortion) are explained in a non-mathematical way.
Also contains two examples of observations by a moving observer:
We fly by Saturn and the Sun.
The motion of
is more complex than a simple translation. All of the visual effects
described in the articles above can be discovered here.
The main article
Through the city at nearly the speed of light
describes a virtual world with a speed of light so low that a biker can
nearly reach it. In this world we ride a bike at nearly the speed of light
through the old city centre of Tübingen.
The striking images are caused by the phenomenon of aberration, explained
in a non-mathematical way in this article.
Visual observations in high speed flight
gives another example of observations while in
high-speed motion: passing throught the Brandenburg Gate in Berlin.
In this article you can find a simple mathematical derivation of the
aberration formula. There are also suggestions for making your own
computer simulations of high-speed flights.
Relativistic flight through a lattice
is an interactive simulation in which you can choose the flight velocity.
The Java code can be used as a starting point for your own computer
This may equally well be regarded
as the simulation of a moving
lattice seen by a stationary observer (principle of relativity).
There is additional information in the following articles that,
based on their main topics, belong to other subject areas:
The simplest approach to aberration, a qualitative argument
making use of everyday experiences, is described in
Destination Black Hole.