Julian Barbour is a profound and original thinker with the boldness to tackle some of nature's deepest problems. He is also a fine writer, and this renders his book - despite its conceptual depth - accessible to anyone who has pondered the mysteries of space and time -- Martin Rees, Astronomer Royal and former President of the Royal SocietyWith a rare humanity and a perspective based on a lifetime of study, Barbour writes a book that is both a work of literature and a masterpiece of scientific thought -- Lee Smolin, author of The Trouble with PhysicsThe origin of the arrow of time is arguably the most important conceptual problem in cosmology, and the prospect that it can be solved in a universe where time flows "backward" in the far past is as exciting as it is provocative. In this engaging book, Julian Barbour conveys this excitement admirably -- Sean Carroll, author of From Eternity to HereThe Janus Point shows history-in-the-making: a project to recast the foundations of all of cosmology, gravity, thermodynamics and the arrow of time. The book has given me a lot to ponder. As Gauss said of Riemann's habilitation lecture, '[it] exceeded my expectations' -- Bill Unruh, Professor of Physics at University of British ColumbiaJulian Barbour has no peer when it comes to explaining scientific ideas in a way that is accessible without being simplistic -- Neal Stephenson, author of Snow Crash Biografía del autor Julian Barbour is a former Visiting Professor in Physics at the University of Oxford and author of the highly regarded The Discovery of Dynamics and the bestseller The End of Time. His papers have been published in the world's most prestigious scientific journals, including Nature, Proceedings of the Royal Society and Physical Review Letters and he has made numerous appearances on national radio, television and in various documentaries. The Janus Point is his first book in twenty years and the culmination of five decades' work.