The End of Time (book)

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The End of Time: The Next Revolution in Our Understanding of the Universe, also sold with the alternate subtitle The Next Revolution in Physics, is a 1999 science book in which the author Julian Barbour argues that time exists merely as an illusion.

Auto-biography[edit]

The book begins by describing how Barbour's view of time evolved. After taking physics in graduate school, Barbour became obsessed with the idea that time is nothing but change. He encountered the work of Paul Dirac which turned his attention to the results of quantum physics. He worked as a translator of Russian scientific articles, providing him plenty of time to pursue his research as he desired.

Possibility[edit]

Cognizant of the counter-intuitive nature of his claim, Barbour eases the reader into the topic by first endeavouring to persuade the reader that our experiences are, at the very least, consistent with a timeless universe, leaving aside the question as to why one would hold such a view.

Barbour points out that some sciences have long done away with the "I" as a persisting identity. To take atomic theory seriously is to deny that the cat that jumps is the cat that lands, to use an illustration of Barbour's. The seething nebula of molecules of which we, cats, and all matter are made is ceaselessly rearranging at incomprehensibly fast speeds. The microcosm metamorphoses constantly, therefore one must deny there is any sense to say a cat or a person persists through time.

Early on, Barbour addresses the charge that writing with tensed verbs disproves his proposal. The next revolution in physics will undermine speaking in terms of time, he says, but there is no alternative.

If a universe is composed of timeless instants in the sense of configurations of matter that do not endure, one could nonetheless have the impression that time flows, Barbour asserts. The stream of consciousness and the sensation of the present, lasting about a second, is all in our heads, literally. In our brains is information about the recent past, but not as a result of a causal chain leading back to earlier instants. Rather, it is a property of thinking things, perhaps a necessary one to become thinking in the first place, that this information is present. In Barbour's words, brains are "time-capsules". He investigates configuration spaces and best-matching mathematics, fleshing out how fundamental physics might deal with different instants in a timeless scheme. He calls his universe without time and only relative positions "Platonia" after Plato's world of eternal forms.

Plausibility[edit]

Why, then, is the instant in configuration space, not matter in space-time, the true object and frame of the universe? He marshals as evidence a non-standard analysis of relativity, many-worlds theory and the ADM formalism. Since, he believes, we should be open to physics without time, we must evaluate anew physical laws, such as the Wheeler–DeWitt equation, that take on radical but powerful and fruitful forms when time is left out. Barbour writes that our notion of time, and our insistence on it in physical theory, has held science back, and that a scientific revolution awaits. Barbour suspects that the wave function is somehow constrained by the "terrain" of Platonia.

Barbour ends with a short meditation on some of the consequences of "the end of time". If there is no arrow of time, there is no becoming, but only being. "Creation" becomes something that is equally inherent in every instant.

There is no general agreement that the ideas expressed in the book have any predictive power and thereby constitute a scientific theory.

Editions[edit]