In a parallel world in which Neanderthals, rather than homo sapiens, became the dominant intelligent species, a dangerous scientific experiment traps a Neanderthal physicist on Earth.
In the near future, an alien craft lands outside the Royal Ontario Museum in Toronto. A six-legged, two-armed alien named Hollus relates to paleontologist Tom Jericho that the Earth, Hollus's home planet, and the planet of another alien species all experienced the same five cataclysmic events that prove the existence of God.
In the near future, a signal is detected coming from the Alpha Centauri system. Mysterious, unintelligible data streams in for ten years. Heather Davis, a professor in the University of Toronto psychology department, has devoted her career to deciphering the message. Her estranged husband, Kyle, is working on the development of artificial intelligence systems and new computer technology utilizing quantum effects to produce a near-infinite number of calculations simultaneously. When Heather achieves a breakthrough, the message reveals a startling new technology that rips the barriers of space and time, holding the promise of a new stage of human evolution. In concert with Kyle's discoveries of the nature of consciousness, the key to limitless exploration---or the end of the human race---appears close at hand. Sawyer has created a gripping thriller, a pulse-pounding tour of the farthest reaches of technology. Factoring Humanity is a 1999 Hugo Award Nominee for Best Novel.