Steinhardt, Paul J.

PERSONAL:

Education: California Institute of Technology, B.S., 1974; Harvard University, M.A., 1975, Ph.D., 1978.

ADDRESSES:

Office— Department of Physics, Princeton University, Princeton, NJ 08544-0708. E-mail— steinh@princeton.edu.

CAREER:

University of Pennsylvania, Philadelphia, physics and astronomy faculty member, 1981-1998, Mary Amana Wood Professor, 1989-1998; Princeton University, faculty member, department of astrophysical sciences, 1998—, professor of physics, 1998-2001, Albert Einstein Professor in Science, 2001—, associate director and senior fellow, Center for Theoretical Physics, 2006—.

MEMBER:

American Physical Society (fellow); Sigma Xi; American Astronomical Society; National Academy of Sciences.

AWARDS, HONORS:

P.A.M. Dirac Medal, International center for Theoretical Physics, 2002.

WRITINGS:

(Editor, with P. Langacker Weldon)Fourth Workshop on Grand Unification, University of Pennsylvania, Philadelphia, April 21-23, 1983, Birkhauser (Boston, MA), 1983.

(Editor, with D.P. DiVincenzo)Quasicrystals: The State of the Art, World Scientific (River Edge, NJ), 1991.

(With Neil Turok)Endless Universe: Beyond the Big Bang, Doubleday (New York, NY), 2007.

SIDELIGHTS:

Theoretical physicist Paul J. Steinhardt, Albert Einstein Professor of Science at Princeton University, conducts research on problems in particle physics, astrophysics, cosmology, and condensed matter physics. He is an expert on the structure of quasicrystals and, with D.P. DiVincenzo, edited Quasicrystals: The State of the Art. Inspired by the work of Alan Guth, Steinhardt helped to develop the "inflationary model" of the universe, a variation of the "Big Bang" theory. As explained on the KurzweilAI Web site, the inflationary model "proposes a brief period of extraordinary, superluminal expansion in the early university to explain the homogeneity and large-scale structure of the universe." Later, Steinhardt and Neil Turok proposed a radical alternative to this model. Their book,Endless Universe: Beyond the Big Bang, aimed at nonspecialist readers, offers an explanation of this new model.

The book describes what Steinhardt and Turok call "the cyclic universe." In this model, the universe does not experience an initial explosion or inflation but goes through what Los Angeles Times Book Review contributor George Johnson described as "an endless cycle of cosmic thunderclaps." The cyclic model is based on an idea from string theory called M-theory, which posits a total of ten dimensions of space and one of time. The visible universe is like a three-dimensional sheet called a "brane" (short for "mathematical membrane"). As explained by Chronicle of Higher Education writer Richard Monastersky, "The universe we can see happens to be stuck on a four-dimensional brane (three space and one time), and we have no easy way of sensing the extra dimensions." What's more, there are additional branes in the cosmos, and these can move. Speculating on what would happen if another brane collided with ours, Steinhardt and Turok, with colleague Burt Ovrut, theorized that the crash would create so much energy and momentum that our universe would start to expand and experience a Big Bang. This model, however, presented some internal problems that led Steinhardt and Turok to conduct additional research. In their resulting theory, parallel branes collide, sparking a Big Bang, and then retreat a tiny distance. This retreat causes the matter in the universe to cool and expand at an accelerating rate. After billions of years, galaxies become so distant from each other that the universe, in essence, becomes empty. Then a springlike force between branes draws them together again, with this pattern continuing in an infinite cycle. According to Monastersky, Steinhardt and Turok were surprised to find that the cyclic model explains the known facts of the universe as well as the accepted view. "The two models are about poles apart in terms of what they tell us about what happened in the early universe and what events caused them," Steinhardt told him. "And yet they're almost identical in what they produce in the present universe."

Reviewers noted that, though Endless Universe is based on highly abstract concepts that some average readers would likely find unfamiliar, the book is lucid and engaging. As Johnson observed in the Los Angeles Times Book Review, Steinhardt and Turok anticipate readers' questions by providing "mini-crash courses on quantum mechanics, special and general relativity, the history of cosmology and even superstring theory—all in preparation for presenting their minority report." Though Johnson appreciated this thorough grounding, he questioned its necessity, pointing out that the book's audience is probably already informed about the Big Bang theory. A writer for Publishers Weekly, on the other hand, commented the authors' "clearly laid out, equation-free arguments" make the book accessible to general readers. Bryce Christensen, writing in Booklist, hailed Endless Universe as a "wonderfully lucid" book that explains to nonspecialists "much of the exciting debate now taking shape at the very frontiers of science."

For Johnson, much of the book's interest lies in the story of how Steinhardt and Turok became interested in Guth's theory and worked toward their own model of the cosmos. Discover reviewer Laurence Marschall made a similar point, observing that the authors are "eloquent in describing how theoretical physicists puzzle through cosmic problems." Even so, critics pointed out that Steinhardt's and Turok's theory remains controversial. Monastersky reported that "new discoveries are raising the stakes in the debate" because of new evidence that supports the inflation theory. The reviewer noted that Michael S. Turner, a University of Chicago professor of astronomy and astrophysics, remained cautious about accepting the cyclic model, saying that "It's an interesting idea, but there are still a lot of details to be worked out." Though Andreas Albrecht, a University of California at Davis professor of physics who was one of the architects of the inflation theory, told Monastersky that cyclic theory "‘still is a bit of wishful thinking at this stage,’" he added that the model is a "‘great development’ and hails its originators, saying that they are ‘forcing me to sharpen up my thinking and engage them.’"

BIOGRAPHICAL AND CRITICAL SOURCES:

PERIODICALS

Analog Science Fiction & Fact, January 2003, "The New Recycling Universe," p. 80.

Astronomy, September 1999, Tom Yulsman, "Give Peas a Chance: Could an Exotic Object Known as a Pea Instanton Have Given Birth to Our Universe?," p. 38; July-August, 2007, Harold Geller, "Endless Universe: A New History of the Cosmos," p. 156.

Booklist, April 15, 2007, Bryce Christensen, review of Endless Universe: Beyond the Big Bang, p. 12.

Chronicle of Higher Education, June 7, 2002, Richard Monastersky, "Recycling the Universe: New Theory Posits That Time Has No Beginning or End."

Discover, December 2002, "Physicists Andrei Linde of Stanford, Alan Guth of MIT, and Paul Steinhardt of Princeton Received the 2002 Dirac Medal for Theoretical Physics, Awarded by the Abdus Salam International Center for Theoretical Physics in Trieste, Italy," p. 16; July 1, 2007, Laurence Marschall, "Coming Soon: The Next Big Bang," p. 73.

Los Angeles Times Book Review, August 5, 2007, George Johnson, review of Endless Universe.

New York Times, April 29, 2003, Dennis Overbye, "Under Prodding, Cosmologists Debate, Well, Everything," p. 3.

Publishers Weekly, April 9, 2007, review of Endless Universe, p. 45.

Science, April 13, 2001, Charles Seife, "Big Bang's New Rival Debuts with a Splash," p. 189; April 26, 2002, Charles Seife, "Eternal-Universe Idea Comes Full Circle," p. 639.

Science Books & Films, July 1, 2007, "520 Astronomy," p. 156.

Science News, August 16, 1986, Dietrick E. Thomsen, "Galaxies Cluster around Cosmic Strings," p. 102; August 11, 2007, review of Endless Universe, p. 95.

ONLINE

American Association for the Advancement of Science,http://www.aaas.org/news/ (October 25, 2007), Paul J. Steinhardt and Neil Turok profile.

Edge: The Third Culture,http://www.edge.org/3rd_culture/ (October 25, 2007), Paul J. Steinhardt profile.

KurzweilAI,http://www.kurzweilai.net/ (October 25, 2007), Paul J. Steinhardt profile.

Princeton University Web site,http://www.phy.princeton.edu/ (October 25, 2007), Paul J. Steinhardt faculty profile.