The Janus Point

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 Society
With 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 Physics
The 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 Here
The 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 Columbia
Julian 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
Julian Barbour has discovered an unexpected and remarkably simple feature of Newtonian dynamics that is the basis of his seductive and eloquently presented explanation of the history of the universe, even time itself -- Michael Victor Berry, Professor of Physics (Emeritus) at Bristol University
This delightful, provocative book is a cosmic physics adventure, enlivened with history and poetry -- Theodore A. Jacobson, Professor of Physics at University of Maryland
Julian Barbour has a complete mastery of the history of ideas yet a remarkable lightness and clarity in explaining what are profound concepts. The Janus Point is controversial and gripping, an extraordinary introduction to his view of the universe -- Pedro G. Ferreira, author of The Perfect Theory
Barbour takes on fundamental questions, offering a new perspective - illustrated with lucid examples and poetically constructed prose - on how the Universe started (or more precisely, how it did not start) and where it may be headed. This book is an engaging read, which both taught me something new about meat-and-potatoes physics and reminded me why asking fundamental questions can be so fun -- Matthew Johnson * Science *
A closely argued, substantive take on one of the biggest unsolved mysteries of physics, written by someone who has wrestled with not only the physics, but also the history and philosophy relevant to his subject. What's more, Barbour's approach, unlike many in the popular science game, is to publish only when he thinks he has something worth saying. That alone is enough to make him worth listening to -- Michael Brooks * Nautilus *
Julian Barbour is one that rare breed, an optimistic scientist, and his engrossing The Janus Point not only turns accepted thinking about the universe on its head...but also suggests our very understanding of the nature of time needs to be reappraised * Choice *
Any reader willing to engage with Barbour's ideas will come away enlightened -- Sidney Perkowitz * Physics World *