The Janus Point

The Janus Point

A New Theory of Time


What is time? The Janus Point offers a ground-breaking solution to one of the greatest mysteries in physics.

For over a century, the greatest minds have sought to understand why time seems to flow in one direction, ever forward. In The Janus Point, Julian Barbour offers a radically new answer: it doesn't.

At the heart of this book, Barbour provides a new vision of the Big Bang - the Janus Point - from which time flows in two directions, its currents driven by the expansion of the universe and the growth of order in the galaxies, planets and life itself. What emerges is not just a revolutionary new theory of time, but a hopeful argument about the destiny of our universe.

'Both a work of literature and a masterpiece of scientific thought' Lee Smolin, author of The Trouble with Physics

'Profound...original...accessible to anyone who has pondered the mysteries of space and time' Martin Rees, Astronomer Royal

'Takes on fundamental questions, offering a new perspective on how the Universe started and where it may be headed' Science Magazine


  • 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

About the author

Julian Barbour

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.
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