New theory on light weighs heavily on scientists

At the heart of Einstein's elegant equation, E=mc2, is the constant speed of light. Indeed, the mind-warping special theory of relativity allows time and space to bend, but light, Einstein insisted, must remain traveling at 186,000 miles per second, throughout the universe, for all observers.

"Whoa!" cries João Magueijo, a young theoretical physicist. This iconoclastic professor at the Imperial College in London has the courage, or some may say the audacity, to challenge that key component of Einstein's deeply ingrained work.

In short, Magueijo claims that some of the most complex mysteries about the origin of the universe can be solved if we consider that light may have traveled much faster at the Big Bang than it does now. In other words, the speed of light is variable.

Many cosmologists today adhere to the idea of "inflation," which speculates that the young universe expanded "unimaginably faster than it does today." But inflation, proposed by MIT physicist Alan Guth in the late 1970s, was never widely adopted by the British theoretical physics community. And Magueijo claims that as an answer to various "cosmological problems ... inflation had won by default." This propelled him to think about another solution.

"I was into my second year as a fellow of St. John's College," he writes, "when one day the answer seemed to drop from the sky. It was a miserable rainy morning - typical English weather - and I was walking across the college's sports field ... when I suddenly realized that if you were to break one simple rule of the game, albeit a sacred one, you could solve these problems."

Challenging any popular or long-held theory in science is a risk, and can even end a promising career. That's especially true when the challenge is being made to the work of a great scientist like Albert Einstein. But Magueijo, with help along the way from a handful of other scientists who were open to discussing the variable speed of light (VSL), kept developing his idea.

Their first attempts to publish a technical paper on the subject, however, ran into what Magueijo characterizes as condescension and purely political opposition. Indeed, the childish, personal nature of these arguments will shock anyone who imagines disinterested scientists searching together for truth.

While Magueijo and his colleagues were battling their work into print, Magueijo discovered that John Moffat, a theoretical physicist at the University of Toronto, already had published a paper on VSL several years earlier. Soon, other papers followed, and the new theory slowly started gaining momentum in the scientific community - even as arguments about who thought of it first burned on.

Magueijo's quirky book is an effort to bring these new ideas to the general public, along with an illuminating peek at these internecine battles among competing scientists and their own stiff conceptions of what's right and what's crazy. After all, he warns, "That's science. Every new idea is gibberish until it survives ruthless challenge."

No one knows yet whether or not VSL is correct - a colleague told him it stood for "very silly" - but Magueijo claims that all the disdain from his detractors and the fight for publication was worth it. "I hope I have shown that science is above all a rewarding human experience," he writes, "perhaps the purest one on offer in a world too often less than perfect."

Strikingly candid, the book brings esoteric scientific concepts within reach of nonscientists. Magueijo proves to be a master at taking complex theories and explaining them in simple terms, such as illustrating the speed of light by describing how cows jump back from the shock of an electric fence.

He also provides a thoroughly engaging, if breezy, portrait of Einstein. Despite the fact that Magueijo hopes to overturn the master's most famous equation, he obviously resonates with the iconoclastic example that this "daydreamer" set for scientific inquiry.

And he shows the human side of building a scientific theory, the side behind the black and white formulas, where red-blooded, passionate humans argue to defend their ideas and their life's work. Indeed, he doesn't hesitate to share his frustration with those who maintain the status quo or who disagree with him, as well as for the red tape that sometimes strangles the willpower out of otherwise aspiring researchers.

"Faster Than the Speed of Light" is part science, part biography, and part adventure, a book that takes us behind the closed doors of the intellectual elite and sheds light on the pettiness and brilliance of speculations and theories that ultimately may change our lives and our beliefs.

• Lori Valigra is a science writer living in Cambridge, Mass.