Four into three

In Factoring Humanity, Canadian science fiction writer Robert
Sawyer’s characters are academics in quantum computing,
artificial intelligence and psychology, a useful combination
when it comes to deciphering messages from an alien race.
Suffice to say that a tesseract (a three-dimensional representation
of a four-dimensional construct) is a major plot device. Sawyer’s
finest novel to date also explores a troubling contemporary
phenomenon, false memory syndrome induced by a dodgy
therapist. Scientifically plausible, fictionally intriguing and
ethically important. Published by HarperCollins/Voyager, £5.99,
ISBN 0006511864.