The fourth book in the Science ofDiscworld series, and this time around dealing with THE REALLY BIGQUESTIONS, Terry Pratchett’s brilliant new Discworld storyJudgement Dayis annotated with very big footnotes (the interleaving chapters) bymathematician Ian Stewart and biologist Jack Cohen, to bring you amind-mangling combination of fiction, cutting-edge science andphilosophy.Marjorie Daw is a librarian, and takes her job –and indeed the truth of words – very seriously. She doesn’t know it, buther world and ours – Roundworld – is in big trouble. On Discworld, acolossal row is brewing…The Wizards of Unseen Universityfeel responsible for Roundworld (as one would for a pet gerbil). Afterall, they brought it into existence by bungling an experiment in QuantumThaumoDynamics. But legal action is being brought against them byOmnians, who say that the Wizards’ god-like actions make a mockery oftheir noble religion.As the finest legal brains in Discworld (a zombie and a priest) gird their loins to do battle –andwhen the Great Big Thing in the High Energy Magic Laboratory isswitched on – Marjorie Daw finds herself thrown across the multiverseand right in the middle of the whole explosive affair.AsGod, the Universe and, frankly, Everything Else is investigated by thetrio, you can expect world-bearing elephants, quantum gravity in theEscher-verse, evolutionary design, eternal inflation, dark matter,disbelief systems – and an in-depth study of how to invent a bettermousetrap.