C. E. Harle, R. Bianconi

light rays are red, observers are blue and magenta (these work as a sort of

This will be a book on the foundations of Special Relativity from a
*synthetic* viewpoint. This means that we start from a few
postulates on how to represent light rays and the principle of inertia
and using Einstein's idea of *light clocks* we define
the notion of measure of time and distance (and simultaneity)
and introduce coordinates *a posteriori*.

The book has a strong visual appeal, modelling with affine geometry. As a subproduct we develop several geometric algorithms which allow us to write programs to visualize relativistic motions.

Download a preliminary version (The two and three dimensional spacetimes) in gzipped postscript format. NEW (May, 2001: Beware of the typographic (and, I am afraid, other) errors. Sorry, not yet fully proofread ;-)

Things to come:

- Some odds and ends in the three dimensional model (hyperboloid of synchronization, etc).
- The four dimensional model: how to do four dimensional descriptive geometry!
- The geometry of the visual effects in special relativity (apparent shape and, I hope, colour).

LAST UPDATE: December 6, 1999.