UNDER CONSTRUCTION
C-ship: Relativistic ray traced images


I've just started to put this document together. It's very incomplete at the moment, and is going to be in a state of flux as I assemble the pieces. Here's where I'm going: I've developed extensions to the freely available Persistence of Vision raytracer (POVRAY) which allow you to specify a velocity vector ("boost" in SR-speak) with any direction and magnitude between 0 and c. Images created reflect Lorentz contraction in the direction of motion, aberration (assuming all objects in the scene are infinitely distant), and the Doppler shift. You can select the effects independently to better understand how they interact.

These effects will be explored through voyages of the "C-ship", a vehicle powered by matter/antimatter annihilation capable of constant acceleration at 10 g. Both static images and animations of relativistic flight will be linked to this page, with the mathematical background behind each image linked to it.

Source code for the relativistic extensions to POVRAY will be posted here for FTP download, with instructions that encourage readers to make their own images of relativistic flight.

This project was inspired by George Gamow's "Mr. Tompkins in Wonderland".

It feels a little strange scribbling away knowing that people all over the world can look over my shoulder at the work in progress as it emerges. But what the heck. If you notice something that doesn't look right, let me know by E-mail and I'll check it out. I tend to write by generating great masses of clumsy and poorly organised prose, then revising it into something vaguely coherent in repeated edit passes. Please keep in mind that what you're reading here amounts to a first draft.


Welcome aboard C-ship, exploring flight near the speed of light! C-ship helps you understand Einstein's theory of Special Relativity intuitively through the medium of computer-synthesised images. We'll explain how to obtain and use the tools used to create the C-ship images, so you can explore relativistic flight on your own computer.

To view the images in this document, you need a graphics-oriented Web browser such as Mosaic or Netscape.

We'll be looking at lots of pictures on our journey. Sending large pictures across the Internet consumes precious network bandwidth and can take a long time. So, I'll show small "thumbnail" views of most pictures, with words "GIF" and "JPEG" beneath the image. When you click on the word, you'll see the full-size image. Most of the images are understandable from the thumbnail views. It's up to you which images you'd like to examine in more detail. If your browser supports in-line JPEG images, click on JPEG, otherwise use GIF. JPEG images look much better and take much less time to transmit to your computer, but not all Web browsers currently understand them.

Our Sturdy Craft

The Lattice Galaxy

The Effects of Special Relativity

The Lorentz Contraction

The Dilation of Time

The Doppler Shift

The Aberration of Light

Our Missions of Exploration

Mission: Flying through the Lattice

Mission: Trans-Lattice Shuttle

Your Turn to Explore

Making Your Own C-ship Images

References and Further Reading


by John Walker
kelvin@fourmilab.ch