Kaku - Parallel worlds a journey through creation, higher dimensions, and the future of the cosmos

This book is dedicated to my loving wife, Shizue.

ACKNOWLEDGMENTS

I would like to thank the following scientists who were so gracious in donating their time to be interviewed. Their comments, observations, and ideas have greatly enriched this book and added to its depth and focus:

Steven Weinberg, Nobel laureate, University of Texas at Austin

Murray Gell-Mann, Nobel laureate, Santa Fe Institute and California Institute of Technology

Leon Lederman, Nobel laureate, Illinois Institute of Technology

Joseph Rotblat, Nobel laureate, St. Bartholomews Hospital (retired)

Walter Gilbert, Nobel laureate, Harvard University

Henry Kendall, Nobel laureate, Massachusetts Institute of Technology (deceased)

Alan Guth, physicist, Massachusetts Institute of Technology

Sir Martin Rees, Astronomer Royal of Great Britain, Cambridge University

Freeman Dyson, physicist, Institute for Advanced Study, Princeton University

John Schwarz, physicist, California Institute of Technology

Lisa Randall, physicist, Harvard University

J. Richard Gott III, physicist, Princeton University

Neil de Grasse Tyson, astronomer, Princeton University and Hayden Planetarium

Paul Davies, physicist, University of Adelaide

Ken Croswell, astronomer, University of California, Berkeley

Don Goldsmith, astronomer, University of California, Berkeley

Brian Greene, physicist, Columbia University

Cumrun Vafa, physicist, Harvard University

Stuart Samuel, physicist, University of California, Berkeley

Carl Sagan, astronomer, Cornell University (deceased)

Daniel Greenberger, physicist, City College of New York

V. P. Nair, physicist, City College of New York

Robert P. Kirshner, astronomer, Harvard University

Peter D. Ward, geologist, University of Washington

John Barrow, astronomer, University of Sussex

Marcia Bartusiak, science journalist, Massachusetts Institute of Technology

John Casti, physicist, Santa Fe Institute

Timothy Ferris, science journalist

Michael Lemonick, science writer, Time magazine

Fulvio Melia, astronomer, University of Arizona

John Horgan, science journalist

Richard Muller, physicist, University of California, Berkeley

Lawrence Krauss, physicist, Case Western Reserve University

Ted Taylor, atomic bomb designer

Philip Morrison, physicist, Massachusetts Institute of Technology

Hans Moravec, computer scientist, Carnegie Mellon University

Rodney Brooks, computer scientist, Artificial Intelligence Laboratory, Massachusetts Institute of Technology

Donna Shirley, astrophysicist, Jet Propulsion Laboratory

Dan Wertheimer, astronomer, SETI@home, University of California, Berkeley

Paul Hoffman, science journalist, Discover magazine

Francis Everitt, physicist, Gravity Probe B, Stanford University

Sidney Perkowitz, physicist, Emory University

I would also like to thank the following scientists for stimulating discussions about physics over the years that have greatly helped to sharpen the content of this book:

T. D. Lee, Nobel laureate, Columbia University

Sheldon Glashow, Nobel laureate, Harvard University

Richard Feynman, Nobel laureate, California Institute of Technology (deceased)

Edward Witten, physicist, Institute for Advanced Study, Princeton University

Joseph Lykken, physicist, Fermilab

David Gross, physicist, Kavli Institute, Santa Barbara

Frank Wilczek, physicist, University of California, Santa Barbara

Paul Townsend, physicist, Cambridge University

Peter Van Nieuwenhuizen, physicist, State University of New York, Stony Brook

Miguel Virasoro, physicist, University of Rome

Bunji Sakita, physicist, City College of New York (deceased)

Ashok Das, physicist, University of Rochester

Robert Marshak, physicist, City College of New York (deceased)

Frank Tipler, physicist, Tulane University

Edward Tryon, physicist, Hunter College

Mitchell Begelman, astronomer, University of Colorado

I would like to thank Ken Croswell for numerous comments on the book.

I would also like to thank my editor, Roger Scholl, who has masterfully edited two of my books. His sure hand has greatly enhanced the books, and his comments have always helped to clarify and deepen the content and presentation of my books. Last, I would like to thank my agent, Stuart Krichevsky, who has ushered in my books for all these years.

PREFACE

Cosmology is the study of the universe as a whole, including its birth and perhaps its ultimate fate. Not surprisingly, it has undergone many transformations in its slow, painful evolution, an evolution often overshadowed by religious dogma and superstition.

The first revolution in cosmology was ushered in by the introduction of the telescope in the 1600s. With the aid of the telescope, Galileo Galilei, building on the work of the great astronomers Nicolaus Copernicus and Johannes Kepler, was able to open up the splendor of the heavens for the first time to serious scientific investigation. The advancement of this first stage of cosmology culminated in the work of Isaac Newton, who finally laid down the fundamental laws governing the motion of the celestial bodies. Instead of magic and mysticism, the laws of heavenly bodies were now seen to be subject to forces that were computable and reproducible.

A second revolution in cosmology was initiated by the introduction of the great telescopes of the twentieth century, such as the one at Mount Wilson with its huge 100-inch reflecting mirror. In the 1920s, astronomer Edwin Hubble used this giant telescope to overturn centuries of dogma, which stated that the universe was static and eternal, by demonstrating that the galaxies in the heavens are moving away from the earth at tremendous velocitiesthat is, the universe is expanding. This confirmed the results of Einsteins theory of general relativity, in which the architecture of space-time, instead of being flat and linear, is dynamic and curved. This gave the first plausible explanation of the origin of the universe, that the universe began with a cataclysmic explosion called the big bang, which sent the stars and galaxies hurtling outward in space. With the pioneering work of George Gamow and his colleagues on the big bang theory and Fred Hoyle on the origin of the elements, a scaffolding was emerging giving the broad outlines of the evolution of the universe.

A third revolution is now under way. It is only about five years old. It has been ushered in by a battery of new, high-tech instruments, such as space satellites, lasers, gravity wave detectors, X-ray telescopes, and high-speed supercomputers. We now have the most authoritative data yet on the nature of the universe, including its age, its composition, and perhaps even its future and eventual death.

Astronomers now realize that the universe is expanding in a runaway mode, accelerating without limit, becoming colder and colder with time. If this continues, we face the prospect of the big freeze, when the universe is plunged into darkness and cold, and all intelligent life dies out.

This book is about this third great revolution. It differs from my earlier books on physics,