Imaginary Numbers are not Real:
the Geometric Algebra of Spacetime

Steve Gull, 1989

"The mathematics that physicists find useful is precisely that which describes the geometry of space and time.

The definition of the `geometric product' of vectors leads to precise geometrical interpretations, and to many surprising results (even in purely classical physics).

The Geometric Algebra (Clifford Algebra), which it defines, is the most powerful and general language available for the development of mathematical physics."

Here are bootleg scans of my copies of the OHP slides from the original lecture in 1989.

Subsequently the lecture was expanded into a paper, with some alterations and rearrangements. A full postscript version of that paper is available from Geometric Algebra Group's server in Cambridge, as is the latex-to-html conversion behind the links below.

The main sections, with links to the most nearly corresponding OHP slides:

Overheads are stored as 1024x745 two colour gifs (about 20K each). Note that each sheet has a left and right page; the links above may be to either. My apologies for the few characters obliterated when the notes were hole-punched. The individual gifs are available in a directory here.

James Heald, June 1996

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