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A Universe From Nothing: Why there is something rather than nothing by Lawrence Krauss is excellent guide to cutting-edge physics; less good on theology

Editorial: 鈥�The Genesis problem鈥�

IN 1996, Lawrence Krauss visited the Lawrence Berkeley National Laboratory in California. During his time there he gave a talk on his latest idea 鈥� that empty space might contain energy. Afterwards, Krauss recalls, a young physicist came up to him and said, 鈥淲e will prove you wrong!鈥�

That young physicist was Saul Perlmutter, who last month picked up a Nobel prize 鈥� not for proving Krauss wrong, as it turns out, but for proving him right. As part of the team who showed that the universe is expanding ever faster, Perlmutter had defeated his own instincts and confirmed Krauss鈥檚 hunch that 鈥渘othing鈥� is not quite what it seems.

As Krauss elegantly argues in A Universe From Nothing, the accelerating expansion, indeed the whole existence of the cosmos, is most likely powered by 鈥渘othing鈥�. Krauss is an exemplary interpreter of tough science, and the central part of the book, where he discusses what we know about the history of the universe 鈥� and how we know it 鈥� is perfectly judged. It is detailed but lucid, thorough but not stodgy.

It is remarkable to think that, a century ago, quantum theory was barely formed, general relativity was a work in progress and only a few scientists believed there was a beginning to the universe. We have come a long, long way since then by developing scientific tools that have proved themselves both reliable and remarkably fruitful. As Krauss鈥檚 insightful book shows, these days we really can talk with scientific rigour about the history and even the prehistoric origins of our universe.

Yet despite its clear strengths, A Universe From Nothing is not quite, as Richard Dawkins hopefully declares in the afterword, a 鈥渒nockout blow鈥� for the idea that a deity must have kicked the universe into being.

Krauss does want to deliver that blow: towards the end of the book, he promises that we really can have something from nothing 鈥� 鈥渆ven the laws of physics may not be necessary or required鈥�. Ultimately, though, he has to perform a little sleight of hand. Space and time can indeed come from nothing; nothing, as Krauss explains beautifully, being an extremely unstable state from which the production of 鈥渟omething鈥� is pretty much inevitable.

However, the laws of physics can鈥檛 be conjured from nothing. In the end, the best answer is that they arise from our existence within a multiverse, where all the universes have their own laws 鈥� ours being just so for no particular reason.

Krauss contends that the multiverse makes the question of what determined our laws of nature 鈥渓ess significant鈥�. Truthfully, it just puts the question beyond science 鈥� for now, at least. That (together with the frustratingly opaque origins of a multiverse) means Krauss can鈥檛 quite knock out those who think there must ultimately be a prime mover. Not that this matters too much: the juvenile asides that litter the first third of the book (for example, 鈥淚 am tempted to retort here that theologians are expert at nothing鈥�) mean that, by the time we get to the fascinating core of his argument, Krauss will be preaching only to the converted.

聯The multiverse puts the question of what shaped our laws of nature beyond science 鈥� for now聰

That said, we should be happy to be preached to so intelligently. The same can鈥檛 be said about the Dawkins afterword, which is both superfluous and silly. A Universe From Nothing is a great book: readable, informative and topical. Inexplicably, though, Dawkins compares it to On the Origin of Species, and suggests it might be cosmology鈥檚 鈥渄eadliest blow to supernaturalism鈥�. That leaves the reader with the entirely wrong sense of having just ingested a polemic, rather than an excellent guide to the cutting edge of physics. Krauss doesn鈥檛 need Dawkins; a writer this good can speak for himself.