(212) 854-6580 March 8, 1999

rjn2@columbia.edu

It was a goal that eluded Albert Einstein in the last frustrating years of his life: the so-called theory of everything, an equation, or set of equations, that would account for gravity and the other forces of nature and tell us why matter has mass, why the Big Bang occurred and where the universe is going.

Einsteinâs big questions havenât been answered yet, in spite of plenty of gray matter expended on them in this century. But there is a growing consensus among theoretical physicists that a new theory, superstring theory, could be the key that will unlock the mysteries.

For the 99.9 percent of humanity without a Ph.D. in physics or mathematics, the theory has been difficult, if not inaccessible, since academics began formulating it in the early 1970s. That situation has now been remedied with a book-length popularization from Brian Greene, professor of physics at Columbia University. ãThe Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory,ä published in February by W.W. Norton & Co. to enthusiastic reviews, is written in the plainest of English. In his first book, Professor Greene brings the strange and wondrous developments of 20th-century physics to the man on the street.

ãI have all the same questions everyone does,ä said the New York native, by way of explaining how he came to work in theoretical physics. ãÎWhat does it all mean?â and ÎWhat is life all about?âä I realized it wasnât likely that I was going to

be able to answer them, but I did believe that if I could get a thorough familiarity with what the questions were ÷ how is it that there are stars and galaxies and planets and people? ÷ then I would get a certain satisfaction.ä

There certainly seems to be a hunger for Professor Greeneâs approach. A lecture at the American Museum of Natural History on March 1 had to be moved to a larger hall to accommodate the 700 people who showed up to hear him. The book has been on the Los Angeles Times bestseller list for the last three weeks, was number three last week on Amazon.com, and has been hovering just outside the top 15 on the New York Times list. The boyish professor has made what seems, to him at least, an endless procession of television and radio appearances. On May 2, he will appear at the Guggenheim Museum for a lecture and performance collaboration with the award-winning Emerson Quartet, titled, appropriately enough, ãStrings and Strings.ä

Under guise of asking deep philosophical questions, Professor Greene treats readers to a heavy dollop of science, albeit entertainingly. He describes the profound puzzle faced by physicists for the last 50 years: the mutual incompatibility between Einsteinâs theory of general relativity, which governs the behavior of large bodies such as stars and galaxies, and quantum mechanics, developed in the 1920s and 1930s by physicists such as Erwin Schroedinger and Werner Heisenberg, which describes the behavior of infinitesimally small bodies, such as atoms. Both theories have been tested and proven right time and again. Using a series of clever analogies and metaphors, Professor Greene shows how string theory appears to finally solve this dilemma, though the solution requires readers to imagine that the universe contains 10, or possibly 11, dimensions, the extra ones curled up in tiny balls and invisible to observers at human scale.

Those extra dimensions are required because large-scale physics theory breaks down when it is used to describe phenomena at sub-microscopic scale. It predicts particles popping in and out of existence in what physicists have taken to calling a ãquantum foam,ä a violent writhing and churning that permeates all existence. Breaking that foam into extra dimensions allows string theorists to posit the existence of ÷ surprise! ÷ strings, tiny, vibrating loops that underlie all matter. It is precisely the way in which these strings vibrate, through both the familiar and extra dimensions, that predicts whether a region of space is

occupied by an electron, a positron, some other particle, a gravitational force or nothing. At least six more dimensions than the four we observe are required to explain all the variety of particles and forces in the universe.

The theory copes with quantum foam by smearing it out and diluting it to acceptable explanatory levels. By replacing point particles with little loops of string, particles are diluted, as is the quantum foam, just enough to allow quantum mechanics and general relativity to meld smoothly together.

Professor Greene has been working on superstrings for more than a decade, but says itâs still impossible to know when the theory will produce definitely testable proposition, a deficiency he laments. Even so, indirect tests of one feature of the theory, called supersymmetry, will be carried out by particle accelerators within the next decade. He and his colleagues hope that these experimental results will establish that the theory is on the right track.

It is in more theoretical directions that he has contributed to recent progress. In 1990, he and a colleague discovered mirror symmetry, that for every possible shape in the universe, there is a mirror shape that generates an alternate universe with exactly the same properties. Later, he showed that the fabric of space can tear, rebutting Einsteinâs assertion that space can only stretch.

There are still plenty of disbelievers. Renowned British physicist Roger Penrose told the New York Times in January that string theory is ãan example of science being driven by fashion.ä And many other physicists are skeptical of string theory, noting its inability to offer any prediction that could be verified by experimentation. But most agree that no other theory has the internal consistency and explanatory power of superstrings. Professor Greeneâs book does the theory, and public understanding of science, an enormous service.

3.8.99 19,484