Wednesday, 26 July 2000

Brian Greene: The Elegant Universe (1999)

Edition: Jonathan Cape, 1999
Review number: 552

The Elegant Universe is not, as the title might suggest, an examination of the philosophical question of why so much of the operation of the physical universe can be described by relatively simple mathematics. Instead, it is a popular account of superstring theory, currently considered to be a major candidate for a cosmological "theory of everything". Strangely enough, from a mathematical point of view, the picture painted is far from elegant, string theory still being full of supposition, reasoning by analogy and with known problems. The elegance is in the approach; if it did provide, at the end of the day, a unified picture of quantum mechanics and general relativity, it could then be considered elegant in other senses.

The book starts, as many popular science books do, with a description of the origins and theory of general relativity, yet even here it scores over many similar volumes by finding descriptions and illustrations I at least had not seen before, and new details of well known pedagogic analogies such as the rubber sheet model of relativistic curved space.

The focus of the book is the string theory, and an admirable job is made of the task of conveying something of what this incredibly difficult mathematical discipline is about and why it is important, without using any mathematics - no equations at all. (It would probably be rather heavy going to someone who has not at least a reasonable familiarity with popular accounts of quantum mechanics, however.)

Greene is an enthusiast for string theory, and an optimist regarding both the completion of the theory and the description of the universe by the theory. These attributes stem, as does the authoritative nature of the narrative, from his position as an active researcher in the field. Some space is given to the arguments of sceptics, but not much. String theory is certainly a worthwhile area of research in mathematical physics, and probably the current best bet for a theory of everything. Objections mainly stem from the feeling that because of this work in the field tends to be overhyped, or amount to philosophical objections to the idea of an ultimate theory. In the first category falls the frequently made point that superstring research has produced little (if anything) in the way of experimentally verifiable prediction (Greene counters this by pointing to parts of the theory which he feels are close to doing so), or that much of the mathematics is fragmentary (since it is so difficult; only more work can fill in the gaps). The second category is barely touched on, though forming a major part of the discussion in such books as John Horgan's The End of Science or John Barrow's Impossibility. Philosophical speculation is by its very nature difficult to answer, and is was perhaps wise not to stray into this territory.

The Elegant Universe is a fascinating book, a clear account of one of the most complex parts of modern science. It is worth reading by anyone with an interest in the physical investigation of the fundamentals of the universe.

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