Parallel Worlds

PARALLL
WORLDS

A
Journey
Through
Creation,
Higher
Dimensions, and
the Future of the Cosmos

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 velocities—that is, the
universe is expanding. This confirmed the results of Einstein's 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,
Beyond
Einstein and
Hyperspace,
which helped to introduce to the public the new concepts of
higher dimensions and superstring theory. In
Parallel Worlds,
instead of focusing on space-time, I concentrate on the
revolutionary developments in cosmology unfolding within the last several
years, based on new evidence from the world's laboratories and the outermost
reaches of space, and new breakthroughs in theoretical physics. It is my intention
that it can be read and grasped without any previous introduction to physics
or cosmology.

In part 1 of the
book, I focus on the study of the universe, summarizing the advances made in
the early stages of cosmology, culminating in the theory called
"inflation," which gives us the most advanced formulation to date of
the big bang theory. In part 2, I focus specifically on the emerging theory of
the multiverse—a world made up of multiple universes, of which ours is but
one—and discuss the possibility of wormholes, space and time warps, and how
higher dimensions might connect them. Superstring theory and M-theory have
given us the first major step beyond Einstein's original theory; they give
further evidence that our universe may be but one of many. Finally, in part 3,
I discuss the big freeze and what scientists now see as the end of our
universe. I also give a serious, though speculative, discussion of how an
advanced civilization in the distant future might use the laws of physics to
leave our universe trillions of years from now and enter another, more
hospitable universe to begin the process of rebirth, or to go back in time when
the universe was warmer.

With the flood
of new data we are receiving today, with new tools such as space satellites
which can scan the heavens, with new gravity wave detectors, and with new
city-size atom smashers nearing completion, physicists feel that we are entering
what may be the golden age of cosmology. It is, in short, a great time to be a
physicist and a voyager on this quest to understand our origins and the fate of
the universe.

P
A
R
T
O
N
E

THE UNIVERSE