by Neil Turok & Paul J. Steinhardt

I picked up Endless Universe because, like many people, I wanted to read something about recent cosmological theory, especially dark matter and dark energy. The book provides all that and then goes further by postulating a more controversial model than the inflationary one currently in favor. In a recent phone conversation, I mentioned this book and its authors’ ideas to a friend of mine who writes about astronomy for a major scientific magazine and I could hear her rolling her eyes. Suffice it to say, the model put forth in Endless Universe is not widely accepted by the scientific community.

I have no problem with the inflationary model’s premise that the universe will expand forever until it is so diffuse that it is for all practical purposes empty. What I find hard to believe is that ‘everything’ just popped into being one day. From where? One might as well believe in creation theory.Paul Steinhardt and Neil Turok, physicists at Princeton and Cambridge Universities respectively, have an alternative. The idea, in a nutshell, is that rather than one big bang out of nowhere/nowhen, why couldn’t there be a never-ending series of bangs and contractions? This is called the cyclic model and in itself is not a new idea. In the past, the cyclic model was soundly trounced by everything from evidence that the expansion of the universe is speeding up with no end in sight to the Second Law of Thermodynamics. To deal with all this they introduce the multiverse, the idea that there are other universes along other dimensions which exert a gravitational effect on ours that could act to reverse the inflationary effect of dark energy. The bangs themselves are actually our universe whacking into the universe next door from time to time.

The book does a great job of presenting things simply but the midsection does get a bit difficult for layfolk. (’Challenging’ is the word the authors use.) In order to explain what they’re explaining they throw in basic primers on string theory and quantum mechanics. I was able to plow through all that with only the sketchiest idea of what they meant and it was enough. Some of the simple drawings were quite helpful, but the great joy of the book is its enthusiasm. In one touching passage, the authors, both physicists by discipline, pay tribute to the trailblazers of the previous generation, such as Andrei Sakharov and Steven Weinberg:

“In the 1960s and ’70s, most particle physicists judged cosmology to be too speculative and recommended that their students steer clear of it. But a few celebrated theorists… were notable exceptions… As important as the research itself was the impression it left on the younger generation of physicists. The fact that world-renowned scientists would consider this problem worthy of their attention sent the message that cosmology was ripe for exploration by particle physicists. By the early 1980s, a growing band of young particle theorists had begun to follow their pioneering trail and explore other puzzles lurking in the early universe. The two of us were part of this new generation.”

It’s a great read whether you agree with their ideas or not. Steinhardt and Turok provide a good overview of cosmology, including a sympathetic summary of the inflationary model. (Steinhardt is a defector from that camp so he knows the party line well.) There were moments reading this book when I was suddenly struck by the scale of space and time being thrown around here and I felt real awe. That alone is worth the price of admission.

Reviewed by Bill Greene

Endless Universe by Neil Turok & Paul J. Steinhardt
Broadway Books, 2008.
Paper, pgs 284, $14.95
ISBN-10 : 0767915011