Is our universe dying?

Could there be other universes?

In Parallel Worlds, world-renowned physicist and bestselling author Michio Kaku — an author who "has a knack for bringing the most ethereal ideas down to earth" (Wall Street Journal) — takes readers on a fascinating tour of cosmology, M-theory, and its implications for the fate of the universe.

In his first book of physics since Hyperspace, Michio Kaku begins by describing the extraordinary advances that have transformed cosmology over the last century, and particularly over the last decade, forcing scientists around the world to rethink our understanding of the birth of the universe, and its ultimate fate. In Dr. Kaku's eyes, we are living in a golden age of physics, as new discoveries from the WMAP and COBE satellites and the Hubble space telescope have given us unprecedented pictures of our universe in its infancy.

As astronomers wade through the avalanche of data from the WMAP satellite, a new cosmological picture is emerging. So far, the leading theory about the birth of the universe is the "inflationary universe theory," a major refinement on the big bang theory. In this theory, our universe may be but one in a multiverse, floating like a bubble in an infinite sea of bubble universes, with new universes being created all the time. A parallel universe may well hover a mere millimeter from our own.

The very idea of parallel universes and the string theory that can explain their existence was once viewed with suspicion by scientists, seen as the province of mystics, charlatans, and cranks. But today, physicists overwhelmingly support string-theory, and its latest iteration, M-theory, as it is this one theory that, if proven correct, would reconcile the four forces of the universe simply and elegantly, and answer the question "What happened before the big bang?"

Already, Kaku explains, the world's foremost physicists and astronomers are searching for ways to test the theory of the multiverse using highly sophisticated wave detectors, gravity lenses, satellites, and telescopes. The implications of M-theory are fascinating and endless. If parallel worlds do exist, Kaku speculates, in time, perhaps a trillion years or more from now, as appears likely, when our universe grows cold and dark in what scientists describe as a big freeze, advanced civilizations may well find a way to escape our universe in a kind of "inter-dimensional lifeboat."

An unforgettable journey into black holes and time machines, alternate universes, and multidimensional space, Parallel Worlds gives us a compelling portrait of the revolution sweeping the world of cosmology.

"Well-known physicist and author Kaku (Hyperspace) tells readers in this latest exploration of the far reaches of scientific speculation that another universe may be floating just a millimeter away on a 'brane' (membrane) parallel to our own. We can't pop our heads in and have a look around because it exists in hyperspace, beyond our four dimensions. However, Kaku writes, scientists conjecture that branes — a creation of M theory, marketed as possibly the long-sought 'theory of everything' — may eventually collide, annihilating each other. Such a collision may even have caused what we call the big bang. In his usual reader-friendly style, Kaku discusses the spooky objects conjured up from the equations of relativity and quantum physics: wormholes, black holes and the 'white holes' on the other side; universes budding off from one another; and alternate quantum realities in which the 2004 elections turned out differently. As he delves into the past, present and possible future of this universe, Kaku will excite readers with his vision of realms that may exist just beyond the tip of our noses and, in what he admits is a highly speculative section, the possibilities our progeny may enjoy countless millennia from now; for instance, as this universe dies (in a 'big freeze'), humans may be able to escape into other universes. B&w illus. Agent, Stuart Krichevsky. First serial to Discover. (On sale Dec. 28)" Publishers Weekly (Copyright 2004 Reed Business Information, Inc.)

"Speculating about escape routes through spacetime, Kaku caps a riveting popular treatment of the string revolution in physics." Booklist (Starred Review)

"Cutting-edge physics for a popular audience....Kaku dutifully steers the reader through the key formulations of physics, with brief glimpses of the scientists behind the big ideas....Ambitious and thought-provoking." Kirkus Reviews

"The acknowledgments listed in this well-researched book read like an honor roll of contemporary astrophysicists and the best science writers. Be prepared to exercise your imagination as you read. Highly recommended." Library Journal

"In Parallel Worlds, Michio Kaku brings his formidable explanatory talents to bear on one of the strangest and most exciting possibilities to have emerged from modern physics: that our universe may be but one among many, perhaps infinitely many, arrayed in a vast cosmic network. With deft use of analogy and humor, Kaku patiently introduces the reader to variations on this theme of parallel universes, coming from quantum mechanics, cosmology, and most recently, M-theory. Read this book for a wonderful tour, with an expert guide, of a cosmos whose comprehension forces us to stretch to the very limits of imagination." Brian Greene, Professor of Theoretical Particle Physics, Columbia University, and author of The Fabric of the Cosmos and The Elegant Universe

"Those who might enjoy a tour of cosmology, time travel, string theory, and the universe in 10 or 11 dimensions will find no better guide than Michio Kaku, a rare individual who has undertaken research in these subject areas yet also knows well how to present this intriguing, complex material in an engaging and easily assimilable style." Donald Goldsmith, author of The Runaway Universe and Connecting with the Cosmos

"A highly readable and exhilarating romp through the frontiers of cosmology." Martin Rees, author of Our Cosmic Habitat and Our Final Century

"A roller-coaster ride through the universe — and beyond — by one of the world's finest science writers. Michio Kaku shows that the surface familiarity of the physical world conceals a wonderland of weird entities — dark matter and energy, hidden dimensions of space, and tiny loops of vibrating string that hold the cosmos together. In the universe according to Kaku, reality is as mind-bending as the most exhilarating science fiction." Paul Davies, Australian Centre for Astrobiology, Macquarie University, Sydney, and author of How to Build a Time Machine

"Michio Kaku has done it again. In Parallel Worlds, he deftly transforms the frontier of physics into a kind of amusement park, where you actually have fun while reading about Einstein's relativity, quantum mechanics, cosmology, and string theory. But the real story here is how Kaku invokes these powerful tools to speculate about multiple universes and their philosophical implications for our perceptions of God and the meaning of life." Neil deGrasse Tyson, Astrophysicist and Director of the Hayden Planetarium, New York City, and author of Origins: Fourteen Billion Years of Cosmic Evolution

The author describes the extraordinary advances that have transformed cosmology and remade our understanding of the universe. Leading physicists now envision our universe as one of countless "bubble universes" only millimeters away from each other.

Michio Kaku is the Henry Semat Professor of Theoretical Physics at the Graduate Center of the City University of New York. He is the author of several widely acclaimed books, including Visions, Beyond Einstein, and Hyperspace, which was named one of the best science books of the year by the New York Times and the Washington Post. He hosts a nationally syndicated radio science program and has appeared on such national television shows as Nightline, 60 Minutes, Good Morning America, and Larry King Live.