A Brief History of Time by Stephen Hawking

First published: 1988

Type of work: Science

The Work:

Stephen Hawking’s popularization of modern cosmology, A Brief History of Time: From the Big Bang to Black Holes, made publishing history (and the Guinness Book of Records) when it remained on the London Times’ best-seller list for more than four years, much longer than any previous book. It was also extraordinarily successful in the United States and other countries and was translated into more than sixty languages. For a work dealing with abstruse astrophysical concepts to sell more than nine million copies was surprising, even to its author. Variously characterized as a landmark in scientific writing and the most popular scientific text of all time, it was also chosen as one of the one hundred most important books of the twentieth century, and a Cambridge University poll ranked it as the book “most likely” to have the same influence as Charles Darwin’s On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for Life (1859).

Because of the phenomenal success of A Brief History of Time, Hawking published a series of corrected, updated, and expanded editions, including a tenth-anniversary edition and an illustrated edition with more than 240 photographs, diagrams, and computer-generated images. An abridged and simplified version was published in 2005. American film director Steven Spielberg, who had met Hawking, produced Errol Morris’s successful documentary A Brief History of Time, released in 1991, which documented Hawking’s life and accomplishments. The film’s success led to the publication of a reader’s companion to the film and book. The success of the companion in turn led to a six-part television miniseries, Stephen Hawking’s Universe, first televised in 1997. In 2008, The Illustrated A Brief History of Time was combined with the illustrated version of Hawking’s The Universe in a Nutshell (2001), demonstrating the book’s continuing popularity.

Critics, scholars, and even Hawking’s mother developed various explanations for the book’s exceptional success. Hawking’s publisher, who had warned him that every mathematical equation included in the text would halve the book’s sales, felt that the absence of mathematics—with the exception of Albert Einstein’s famous expression of the relationship between matter and energy—played a role in the book’s popularity. Some commentators attributed the book’s prodigious sales to the author’s genuine talent for using similes, analogies, and humor to make complex mathematical and physical ideas understandable to lay readers. Others thought that, like Einstein, Hawking was able to communicate to ordinary readers his childlike wonder over the mysteries of the universe and the joy of discovering the solutions to some of these mysteries.

More controversially, a few critics admonished the book’s publisher for exploiting Hawking’s disabilities for commercial purposes. For most of his life, Hawking has suffered an increasingly debilitating case of amyotrophic lateral sclerosis, which requires him to use a wheelchair (as depicted on the front of the book’s dust jacket). His mother responded that her son’s ability to overcome his handicaps and become a very successful scientist and science popularizer served as an example of inspiration, not exploitation. Hawking himself has stated that he wrote the book, which took him over five years, to help provide for his family, especially for the education of his children.

In A Brief History of Time, Hawking tries to answer certain basic questions that nonscientists have about the universe. For example, how did it originate, how will it end, how is it structured, and is it finite or infinite? To communicate how modern scientists answer these questions, Hawking uses two fundamental theories: general relativity and quantum mechanics. General relativity is Einstein’s theory, involving innovative ideas of space, time, matter, and gravity that enabled him and others to deepen their understanding of the large-scale structure of the universe. Quantum mechanics, developed by the German physicist Werner Heisenberg and others, enabled scientists to understand puzzling phenomena at the subatomic level. Like all theories, relativity and quantum mechanics are provisional. They are not even consistent with each other. Nevertheless, they superseded the model of matter and the universe that had been formulated by Sir Isaac Newton, whose mathematical description of gravity as a mutual attractive force was able to account for the elliptical orbits of the planets and many other physical phenomena. Hawking, who, like Newton, was Lucasian Professor of Mathematics at Cambridge University, strongly identified with his predecessor’s quest to determine the basic laws of the universe.

This quest for fundamentals also characterized the career of Einstein, who, after postulating that physical laws remained invariant in uniformly moving systems, rejected Newton’s belief in absolute space, time, and simultaneity, because all three depend on the relative speed of an observer. Using the equivalence between gravity and acceleration, Einstein also formulated a general theory of relativity that applied even to nonuniformly moving systems, but, in what he later called the greatest blunder of his career, he modified his equations to account for what astronomers then assumed to be a static universe. However, in 1929, the American astronomer Edwin Hubble made observations that indicated that the universe is dynamic, or expanding. By extrapolating this expansion backward in time, other scientists formulated a theory of the universe’s origin that was called the “big bang,” in which a cosmic explosion of superdense matter about twelve billion years ago resulted in the cosmos observed today.

Hawking, using the mathematics of general relativity, proved that the universe had to have a beginning in what he termed a “singularity,” an infinitesimally small point in space-time at which matter is compressed into an unimaginably dense state. In his book, Hawking discusses inflation, a theory describing the sudden expansion of this compressed matter within a fraction of a second of the universe’s beginning. The way he discussed how credit should be assigned for certain aspects of this inflationary model proved seriously damaging to the reputation of a young scientist, and he changed the offending passage in the next edition of his book.

Because Hawking’s most significant achievements have been in the field of black holes, he devotes the central chapters of his book to an investigation of them and their properties. He defines a black hole as a region of colossally compressed matter whose gravitational force is so strong that nothing, not even light particles, can escape it. When Hawking first began to study black holes, considerable uncertainty prevailed about their actual existence, but most astronomers came to agree with him that black holes exist not only in the Milky Way galaxy but in other galaxies as well. Observations made with the Hubble telescope indicate that extremely large black holes may exist at the centers of quasars, staggeringly distant objects that are many times brighter than all the stars in the Milky Way galaxy.

In the 1970’s, Hawking began thinking about ways of distinguishing space-time points both within and outside a black hole. The boundary, or “event horizon,” of a black hole designates the “point of no return” between this hole and the outside universe. By investigating this event horizon, Hawking found that “black holes ain’t so black” (the title of one of his chapters). He then used quantum ideas to study the behavior of particles just outside the event horizon and made the surprising discovery that a black hole could emit subatomic particles. Now called “Hawking radiation,” these ejected particles mean that black holes lose mass—large black holes very slowly, small black holes very rapidly. (Hawking also did important work on such “mini-black holes.”) As a black hole loses matter and energy, its event horizon gradually contracts, leading to an important question about information and black holes. Hawking believed that when matter is compressed into a black hole, the result is the loss of all its information, such as mass, charge, and so on. Other scientists attacked this view, which Hawking continued to defend in later editions of his book, but in 2004 he finally admitted that he had been wrong. He was converted to the view that information about a black hole’s matter can filter to the outside universe, perhaps through certain properties of Hawking radiation.

The final chapters of Hawking’s book deal with the fate of the universe, which depends on which theory designed to unify general relativity and quantum mechanics turns out to produce the most accurate predictions. In one of these theories, the universe’s history is analogous to the Earth’s three-dimensional surface, which is finite in size but has no boundary. In a multidimensional model using the no-boundary condition, the story of the universe begins with a period of rapid expansion, with the density of matter varying from place to place. As time proceeds, the ultimate fate of this matter—continued expansion or eventual contraction—will be determined by the total amount of all kinds of matter and energy in the cosmos, including invisible or “dark” matter and hidden or “dark” energy, with the latter as the cause of the accelerating rate of the universe’s expansion. Hawking favors a cosmos that is completely self-contained, with no boundaries and with no reference to anything outside it. In this view, he argues, God is not needed to give the universe its start, but other views of the universe, based on the unification of quantum and relativity theories, are possible. Hawking insists that any such theory, if it is discovered, should, at least in its basic thrust, be understandable by everyone. Humans will then know why the universe exists. He concludes his book with a sentence that has been often cited, criticized, and discussed: “If we find the answer to [this unification], it would be the ultimate triumph of human reason—for then we would know the mind of God.”

The response of scientists, scholars, and the public to A Brief History of Time was overwhelmingly positive. Some scholars viewed the book as the culmination of a tradition of the popularization of physics and cosmology that had begun in the early twentieth century with Einstein and others. Nonscientists were willing to tackle the book’s complex ideas because discoveries of human and especially nonhuman space exploration had made them curious about the universe, and the spectacular pictures from the Hubble space telescope kept this curiosity alive through the book’s later editions (whose illustrated versions made use of these photographs). The book generated some controversy among scientists, atheists, and theists. Hawking responded to the scientific critiques by clarifying and correcting certain passages in later editions. Some atheists, bothered by Hawking’s use of God in a scientific work, claimed he was using the Deity as a symbol or metaphor, since they knew he shared their atheism. Some religious reviewers found Hawking’s analysis of theological arguments and the Bible less than enlightened. His religious views also played a role in the breakup of his marriage to Jane Wilde, who was a deeply committed Christian. This is ironic, since A Brief History of Time is dedicated to her. However, criticisms of the book and the troubles in Hawking’s personal life did little to dampen the enthusiasm of succeeding generations of readers, who continued to find his guide to the cosmos congenial and enlightening.

Bibliography

Ferris, Timothy. The Whole Shebang: A State-of-the-Universe(s) Report. New York: Simon & Schuster, 1997. The author, a prize-winning science popularizer, explains for general readers how scientists, including Hawking, envision the universe as a whole. He also surveys modern cosmological research and speculates on future trends. Extensive notes, glossary, and index.

Guth, Alan H. The Inflationary Universe: The Quest for a New Theory of Cosmic Origins. Reading, Mass.: Addison-Wesley, 1997. Just as Hawking analyzed Guth’s ideas in A Brief History of Time, so Guth analyzes Hawking’s views in this popular treatment of the second before the big bang, when the rapid inflation that started the universe began. Illustrated, with notes, glossary, and index.

Hawking, Stephen, assisted by Gene Stone. Stephen Hawking’s “A Brief History of Time”: A Reader’s Companion. New York: Bantam Books, 1992. Expands the material covered by both book and film. Illustrated with photographs. Glossary and index.

Larsen, Kristine. Stephen Hawking: A Biography. Westport, Conn.: Greenwood Press, 2005. Explores for lay readers both the personal life and the scientific achievements of its subject. Notes at the ends of chapters, a helpful time line, and a glossary. Select bibliography and index.

Susskind, Leonard. The Black Hole War: My Battle with Stephen Hawking to Make the World Safe for Quantum Mechanics. New York: Little, Brown, 2008. The author wrote this book for a wide audience to explain why Hawking was wrong in stating that information is lost when black holes evaporate and that he is right in explaining, in agreement with classical and quantum physics, how some information is preserved. Glossary and index.

White, Michael, and John Gribbin. Stephen Hawking: A Life in Science. 1992. Rev. ed. Washington, D.C.: Joseph Henry Press, 2002. Details Hawking’s life and work through the early twenty-first century. Some reviewers called this “the definitive portrait” of the person whom posterity will regard as the “new Einstein,” an estimation denied by Hawking. References and index.