The Janus Point

What is time? Why is the past so different from the present and the future? This simple question is in fact one of the deepest, most long-standing problems in physics. None of the known laws of the universe can fully explain it. In The Janus Point , Julian Barbour presents a bold new thesis and a possible solution, with radical implications for our understanding of the Big Bang and the nature of time itself. His argument rests on two vital insights. The first is that the most common explanation for time - entropy - is flawed: firstly, because we have no way of explaining how the concentration of energy that would allow the Big Bang to take place came about, and secondly because none of our understanding of entropy takes into account the fact that the universe is infinitely expanding. In addition, our universe is actually becoming ever more complex and ordered as it expands, not less so. The second is a phenomenon which Barbour labels ''The Janus Point'': any system of particles in motion will pass through a single moment of smallest size, never to be repeated. Combining these two observations, Barbour argues that the universe, and therefore time itself, may not have begun at the Big Bang, but rather at The Janus Point, thus solving the conundrum of entropy. Monumental in vision and scope, The Janus Point offers a ground-breaking challenge to our understanding of the universe and a brilliant solution of breath-taking elegance and import to this most fundamental of problems.

Autorentext

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.

Klappentext

In The Janus Point renowned physicist Julian Barbour presents a major new solution to one of the most profound questions in physics - what is time? - with ground-breaking implications for the origin and destiny of our universe.

'Both a work of literature and a masterpiece of scientific thought' Lee Smolin

Time is perhaps the greatest mystery in physics. Despite the fact that the fundamental laws of physics don't distinguish between past and future, we do. And so, 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, author of the classic The End of Time, offers a radically new answer: it doesn't.

Most physicists believe that the second law of thermodynamics, and the increase of disorder that it describes, forces an irreversible, unidirectional flow of time. Barbour shows why that argument fails and demonstrates instead that our universe isn't heading for disorder; rather, it emerged from it. At the heart of his argument is a new vision of the Big Bang that Barbour calls 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.

Monumental in vision and scope, The Janus Point is not just a new theory of time: it's a hopeful argument about the destiny of our universe. While most physicists predict that the universe will become mired in disorder, Barbour sees the possibility that order - the stuff of life - can grow without bound.