Jim and I decided that this was the most natural choice of class, indeed the only natural choice. We formulated the no-boundary proposal: that the boundary condition of the universe is that it is closed without boundary. According to the no-boundary proposal, the beginning of the universe was like the South Pole of the Earth, with degrees of latitude playing the role of imaginary time. The universe would start as a point at the South Pole. As one moves north, the circles of constant latitude, representing the size of the universe, would expand. To ask what happened before the beginning of the universe would thus become a meaningless question, because there is nothing south of the South Pole.
Time, as measured in degrees of latitude, would have a beginning at the South Pole, but the South Pole is much like any other point on the globe. The same laws of nature hold at the South Pole as in other places. This would remove the age-old objection to the universe having a beginning—that it would be a place where the normal laws broke down. The beginning of the universe would instead be governed by the laws of science. We had sidestepped the scientific and philosophical difficulty of time having a beginning by turning it into a direction in space.
The no-boundary condition implies that the universe will be spontaneously created out of nothing. At first it seemed that the no-boundary proposal did not predict enough inflation, but I later realized that the probability of a given configuration of the universe has to be weighted by the volume of the configuration. Recently Jim Hartle, Thomas Hertog (another former student), and I have discovered that there is a duality between inflating universes and spaces that have negative curvature. This allows us to formulate the no-boundary proposal in a new way and to use the considerable technical machinery that has been developed for such spaces. The no-boundary proposal predicts that the universe will start out almost completely smooth, but with tiny departures. These will grow as the universe expands, and will lead to the formation of galaxies, stars, and all the other structures in the universe, including living beings. The no-boundary condition is the key to creation, the reason we are here.
13
NO BOUNDARIES
WHEN I WAS TWENTY-ONE AND CONTRACTED ALS, I felt it was very unfair. Why should this happen to me? At the time, I thought my life was over and that I would never realize the potential I felt I had. But now, fifty years later, I can be quietly satisfied with my life. I have been married twice and have three beautiful and accomplished children. I have been successful in my scientific career: I think most theoretical physicists would agree that my prediction of quantum emission from black holes is correct, though it has not so far earned me a Nobel Prize because it is very difficult to verify experimentally. On the other hand, I won the even more valuable Fundamental Physics Prize, awarded for the theoretical significance of the discovery despite the fact that it has not been confirmed by experiment.
My disability has not been a serious handicap in my scientific work. In fact, in some ways I guess it has been an asset: I haven’t had to lecture or teach undergraduates, and I haven’t had to sit on tedious and time-consuming committees. So I have been able to devote myself completely to research.
To my colleagues, I’m just another physicist, but to the wider public, I became possibly the best-known scientist in the world. This is partly because scientists, apart from Einstein, are not widely known rock stars, and partly because I fit the stereotype of a disabled genius. I can’t disguise myself with a wig and dark glasses—the wheelchair gives me away.
Being well known and easily recognizable has its pluses and minuses. The minuses are that it can be difficult to do ordinary things such as shopping without being besieged by people wanting photographs, and that in the past the press has taken an unhealthy interest in my private life. But the minuses are more than outweighed by the pluses. People seem genuinely pleased to see me. I even had my biggest-ever audience when I was the anchor for the Paralympic Games in London in 2012.
I have had a full and satisfying life. I believe that disabled people should concentrate on things that their handicap doesn’t prevent them from doing and not regret those they can’t do. In my case, I have managed to do most things I wanted. I have traveled widely. I visited the Soviet Union seven times. The first time I went with a student party in which one member, a Baptist, wished to distribute Russian-language Bibles and asked us to smuggle them in. We managed this undetected, but by the time we were on our way out the authorities had discovered what we had done and detained us for a while. However, to charge us with smuggling Bibles would have caused an international incident and unfavorable publicity, so they let us go after a few hours. The other six visits were to see Russian scientists who at the time were not allowed to travel to the West. After the end of the Soviet Union in 1990, many of the best scientists left for the West, so I have not been to Russia since then.
Anchoring the Paralympic Games in 2012 (illustration credit 13.1)
Visiting the Temple of Heaven in Beijing (illustration credit 13.2)
I have also visited Japan six times, China three times, and every continent, including Antarctica, with the exception of Australia. I have met the presidents of South Korea, China, India, Ireland, Chile, and the United States. I have lectured in the Great Hall of the People in Beijing and in the White House. I have been under the sea in a submarine and up in a hot air balloon and a zero-gravity flight, and I’m booked to go into space with Virgin Galactic.
My early work showed that classical general relativity broke down at singularities in the Big Bang and black holes. My later work has shown how quantum theory can predict what happens at the beginning and end of time. It has been a glorious time to be alive and doing research in theoretical physics. I’m happy if I have added something to our understanding of the universe.
Meeting Queen Elizabeth II with my daughter, Lucy (illustration credit 13.3)
Experiencing zero gravity (illustration credit 13.4)
For William, George, and Rose
ILLUSTRATION CREDITS
Courtesy of Mary Hawking: fm.1, fm.2, 1.1, 1.2, 1.4, 1.5, 1.7, 2.1, 2.3, 2.7, and 2.8
Courtesy of Stephen Hawking: 1.3, 2.2, 2.4, 2.6, 3.5, 4.3, 6.1, 7.1, 8.1, 9.1, 9.2, 9.3, 9.4, and 11.2
National Archives and Records Administration: 1.6
Herts Advertiser: 2.9
Gillman & Soame: 3.1, 3.2, 3.3, 3.4
Suzanne McClenahan: 4.1
Lafayette Photography: 4.2
John McClenahan: 4.4
Courtesy of the Archives, California Institute of Technology: 8.2 and 8.3
Bernard Carr: 11.1 and 12.1
Judith Croasdell: 13.1
Zhang Chao Wu: 13.2
Alpha/Globe Photos, Inc.: 13.3
Steve Boxall: 13.4
ALSO BY STEPHEN HAWKING
A Brief History of Time
Black Holes and Baby Universes and Other Essays
The Illustrated A Brief History of Time
The Universe in a Nutshell
A Briefer History of Time (with Leonard Mlodinow)
The Grand Design (with Leonard Mlodinow)
FOR CHILDREN
George’s Secret Key to the Universe (with Lucy Hawking)
George’s Cosmic Treasure Hunt (with Lucy Hawking)
George and the Big Bang (with Lucy Hawking)
COMING SOON
George and the Unbreakable Code (with Lucy Hawking)
George and the Space Prospectors (with Lucy Hawking)
ABOUT THE AUTHOR
STEPHEN HAWKING was the Lucasian Professor of Mathematics at the University of Cambridge for thirty years and has been the recipient of numerous awards and honors including, most recently, the Presidential Medal of Freedom. His books for the general reader include the classic A Brief History of Time, the essay collection Black Holes and Baby Universes, The Universe in a Nutshell, and, with Leonard Mlodinow, A Briefer History of Time and The Grand Design.
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My Brief History Page 7
