David Cherniack Films Interview Transcript
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This is take 1. Starting June 20th. Interview with Professor Hawking.

WHEN DID YOU FIRST REALIZE THAT YOU WANTED TO BE A PHYSICIST?

I think I knew from about the age of 9 or 10 that I wanted to be a scientist. And probably from about the age of 15 that I wanted to be a physicist. Because I wanted to understand the basic problems of the universe. And try to understand how the universe works.

IS THIS AN ALL-CONSUMING KIND OF PASSION WITH YOU?

I don't quite know how you define that. Most of my activity is like playing with model fireworks, or model railways or model planes. Or playing complicated games. I was angling at some way of finding out how the world worked around me.

YOU WERE VERY BIG INTO MODELLING. IT'S CONTINUING.

I was never very good with my hands. So my models did not work very well. But I was always interested in models that I could control. Where I think that nowadays I have translated that into studying physics. Because in a way if you understand the universe, then you have control of it.

WHAT EXACTLY, LET'S BACK UP A LITTLE BIT OR LET'S START GETTING INTO PHYSICS, WHAT EXACTLY IS IT THAT A THEORETICAL PHYSICIST DOES?

What a theoretical physicist does is try to construct mathematical models which represent the universe. And which describe the results of observations. And we can say a model is a good model if it has few arbitrary elements, and if it describes all the observation so far made. And if it predicts the result of new observations correctly.

CAN YOU STOP FOR A SEC?

(cut tape)

Slate.

TRADITIONALLY, MUCH OF WHAT YOU SAY A PHYICIST DOES, TRY AND UNDERSTAND WHY THE UNIVERSE IS THE WAY THE UNIVERSE IS, HAS BEEN THE SUBJECT OF RELIGION, AND THERE HAVE OFTEN BEEN CONFLICTS BETWEEN ORGANIZED RELIGION AND THE CHURCH, GALILEOFOR INSTANCE, YOUR PREDECESSOR, 300 YEARS. 20TH CENTURY PHYSICS SEEMS TO HAVE MORE IN COMMON WITH MYSTICISM THAN MATERIALISM. WHAT ARE THE PRINCIPLE PHYSICAL IDEAS THAT HAVE OCCURRED IN THIS CENTURY THAT HAVE SHAPED THAT?

I don't think physics has much contact with mysticism. In fact it's really the very opposite of mysticism. Physics aims to find a rational model for the universe. And mysticism aims to describe the universe basically as a mystery. I think in a way physics has been a progress away from mysticism. Towards a rational understanding of the universe.

OKAY, BUT CERTAINLY IN THE 20TH CENTURY WHAT WE HAVE SEEN IS THE BREAKDOWN OF OUR COMMON EVERY DAY EXPERIENCE, AND OUR COMMON EVERY DAY WAY OF PERCEIVING THE WORLD TENDS TO BREAK DOWN IN MODERN PHYSICS. WHAT I'M GETTING AT IS TWO CENTRAL IDEAS WHICH HAVE OCCURRED IN THIS CENTURY OF RELATIVITY AND QUANTUM MECHANICS, BOTH OF WHICH COMMON SENSE APPROACH TO THE UNIVERSE IN THIS ORDINARY EVERYDAY EXPERIENCE TENDS TO BREAK DOWN COMPLETELY.

I think the whole history of human thought has been steady progress. In which old ideas are replaced by new ideas. You might say that common sense says that the world is flat. However, the ancient Greeks discovered that the world was round. And that must have been just as much of an upset to them as relativity and quantum mechanics are to us.

CAN YOU JUST PAUSE FOR A SECOND?...

(cut tape)

Slate.

Common sense tells us that the world is flat. However, the ancient Greeks discovered that the world was really round. That must have been as big an upset to them as the ideas of relativity and quantum mechanics are to us. Then up to the 15th century, after the 15th century common sense told people that the sun goes round the earth. But then they discovered that the earth really goes round the sun. And that gave rise to a big intellectual revolution. And up to this century we thought that space was flat. But then Einstein showed that one count account for gravity by saying that space time is really curved. And up to this century we thought that you could measure the position and velocity of a particle up to arbitrary accuracy. But then in this century we discovered a new kind of theory called quantum mechanics... which tells us that you cannot measure both the position and the velocity of a particle simultaneously to arbitrary accuracy. The more accurately you measure the position, the less accurately you know the velocity, and visa versa.

SO THIS INTRODUCES THE NOTION OF PROBABILITY INTO THE LAWS OF THE UNIVERSE?

Yes, because particles do not have a well defined position. They just have a probability distribution of being found in different places.

I UNDERSTAND THAT THIS UPSET ALBERT EINSTEIN VERY MUCH.

Einstein could not accept this element of probability or chance. He said that God does not play dice. But all the evidence we have suggests that there really is an element of randomness in the universe.

WHERE ELSE DOES COMMON SENSE BREAK DOWN TO THE LEVEL OF QUANTUM MECHANICS? I'M THINKING NOW OF PARTICLES APPEARING OUT OF NOTHING, WAVE PARTICLE DUALITIES, THINGS LIKE THAT.

What appears to be common sense is very much a function of time. In ancient times it was common sense to say the world was flat. And nowadays, if you were to ask a child, he would be able to tell you that you could travel in a spaceship to visit other planets and galaxies. But most people know rather little about quantum mechanics. Most people know very little about quantum mechanics, and therefore they find it appears to be contradictory to common sense. But maybe in the future when children are brought up in school with the idea of quantum mechanics, and they see it on television, they'll accept the ideas inherent in ...

THERE ARE MANY DIFFICULT IDEAS TO TAKE HOLD OF IN MODERN PHYSICS. ONE OF THEM IS THE NOTION OF A SINGULARITY. WHAT EXACTLY IS A SINGULARITY?

A singularity in space time is a place where the density of matter and the curvature of space time become infinite. And after singularity, the concepts of space and time break down.

SO WE CAN'T SAY ANYTHING ABOUT WHAT THE UNIVERSE IS LIKE...

Well, all the laws of physics are formulated in terms of space time, and therefore out of singularity they break down. In fact we cannot predict what will happen to the singularity.

THE COMMONLY ACCEPTED WAY THAT THE UNIVERSE BEGAN IS AS A SINGULARITY, WITH AN ENORMOUS EXPLOSION CALLED THE BIG BANG, AN ENORMOUS EXPANSION CALLED THE BIG BANG. ACCORDING TO WHAT YOU'RE SAYING THAT MEANS THAT WE REALLY CAN'T SAY ANYTHING ABOUT THE UNIVERSE AT THE POINT IT BEGAN. THIS MUST MAKE PEOPLE WHO BELIEVE IN DIVINE CREATION VERY HAPPY.

(cut tape)

Professor Hawking intv., 20Jun, tape 2.

Slate.

If Einstein's general theory of relativity is correct, the universe began with a singularity called the big bang. Now because it was a singularity, all the laws of physics broke down. And therefore we cannot predict how the universe began. A few years ago I was at a conference on cosmology that was held in the Vatican. And at the end of the conference the participants were granted an audience with the Pope. The Pope said it was fine for them to inquire into the early history of the universe, but they should not ask questions about the big bang itself... because that was the work of God. However, at that conference I proposed that Einstein's general theory of relativity would have to be modified to take quantum mechanics into account. And that modification would mean that there was no singularity. Space time would be finite in extent, but with no singularities. In this picture, space time would be like the surface of the earth. It's finite in extent, but it doesn't have any boundary or edge or singularities.

SO IT WOULDN'T BE POSSIBLE TO SAY THAT REALLY THAT THE UNIVERSE HAS A BEGINNING OR END, OR WHAT WOULD BE POSSIBLE TO SAY ABOUT BEGINNING AND CAUSATION?

The universe... the universe would have a beginning and an end in the same sense that degrees of latitude have a beginning and an end at the north and south poles respectively. There isn't any point with a latitude 91 degrees north. And similarly, there isn't any point in the universe which is before the big bang. And the, but the north pole is a perfectly regular point of the earth's surface, it's not a singular point. And similarly, I believe that the big bang was a perfectly regular point of space time. And all the laws of physics would hold at the big bang. And if that is the case, we can completely predict the state of the universe from the laws of physics.

SO WHAT CAN YOU SAY ABOUT, ...ESSENTIALLY MEANS THAT THE UNIVERSE, YOU CANNOT SAY THAT THE UNIVERSE IS CAUSED, RIGHT? IS THAT CORRECT?

That's right. The universe does not have any beginning or end. It does not have any cause or consequence. It simply is.

YOU HAVE PUT THIS OUT AS UNDER THE WORD PROPOSAL, AND NOT THEORY. WHAT IS THE DIFFERENCE?

There isn't really any difference. There isn't really any difference. Every theory is really proposal. You can't deduce a new theory. You have to make a new proposal. What you do is, you make a new proposal and calculate the consequences. And if they agree with observations then you call it a new theory.

THE CONSEQUENCES OF A THEORY WHICH SAYS THAT THE UNIVERSE IS NOT CAUSED ARE FAR GREATER PROBABLY IN THE REALM OF PHILOSOPHY AND RELIGION THAN THEY ARE IN THE REALM OF PHYSICS. LET'S LEAVE THE QUESTION OF THE PHILOSOPHERS AND THE RELIGIONISTS ASIDE FOR A SECOND. WHAT HAS THE REACTION BEEN TO THE REST OF THE WORLD OF PHYSICISTS? HOW HAVE THEY REACTED TO A CAUSELESS UNIVERSE? AN UNCAUSED UNIVERSE?

I think that most of those who believe my proposal... sorry. I think that most of those who have heard my proposal and understand it, believe it's a possibility. And insofar as it doesn't lead to contradictionist observations, it may be correct.

(cut tape)

Slate.

Most people who understand my proposal believe that it is a possibility. But I think that most of them would reserve judgment as to whether it is correct. But I don't think that anybody believes it is definitely wrong.

WHAT ABOUT THE PHILOSOPHICAL IMPLICATIONS OF WHAT YOU'RE PROPOSING? DOESN'T IT REQUIRE US TO FORM A COMPLETELY DIFFERENT CONCEPTION OF HUMANKIND AND HUMANKIND'S RELATIONSHIP TO A SUPREME DIETY?

Well, most scientists don't like to think too much about philosophical questions. They feel that such questions are really badly defined. And they'd rather stick to questions that they understand.

NEVERTHELESS, THE HISTORY OF DISCOVERIES MADE IN SCIENCE, BOTH THEORETICAL AND PRACTICAL, ARE CONSTANTLY ALTERING THE PREVAILING WORLD VIEW.

That is certainly true, but many scientists feel if they start talking about such questions, they'll be regarded as cranks rather than as serious scientists.

I DON'T KNOW, EINSTEIN SHOULD HAVE KEPT HIS MOUTH SHUT AND NOT SAID ANYTHING ABOUT... OKAY. YOU CARE NOT TO SPECULATE ABOUT WHAT THE PHILOSOPHICAL...

I think that there are important philsophical implications, and that scientists really should think about them. But what I'm saying is that I think most scientists are just rather reluctant to talk about such questions.

THAT MEANS INCLUDING YOU NOW, RIGHT?

No, not including me.

OKAY, SO WHAT KIND OF IMPLICATIONS ARE WE TALKING ABOUT?

Obviously implications about the existence and the nature of God. Is there a God who intervenes in the universe, or one who wound up the clock to set things going? I think with the progress of science, most scientists now believe that God does not intervene in the universe. And they believe that the universe evolves according to laws of science. And that there aren't any exceptions to these laws. But I think that most scientists still reserve judgment on how the universe was set up in the first place. Whether that was an act of God, or whether that too was subject to the laws of science. What I'm suggest is, that it was indeed subject to the laws of science.

WHEN I ASKED THE QUESTION, HOWEVER, I SAID DOES IT NOT REQUIRE A RADICAL RELOOKING AT THE WHOLE RELATIONSHIP BETWEEN WHAT WE CONSIDER A DIVINE BEING, AND OURSELVES? SOME PEOPLE ARE PROPOSING THAT AN EASTERN CONCEPT, OR A CONCEPT BORROWED FROM EASTERN PHILOSOPHY MIGHT SOLVE THE PROBLEM IN THAT THERE DOES NOT HAVE TO BE A CAUSAL RELATIONSHIP BETWEEN SPACE TIME, AND WHAT IS NOT SPACE TIME. THE TWO THINGS SIMPLY ARE.

My opinion is that such ideas don't really explain anything. They merely shroud everything in obscurity.

ALL OF THEORETICAL PHYSICS SEEMS TO BE DIRECTED TOWARDS THE EVENTUAL GOAL, THAT'S A UNIFIED FIELD THEORY, AN UNDERSTANDING ONF FUNDAMENTAL LAWS THAT UNIFY ALL OF NATURE, INCLUDING MANKIND. WILL WE EVER FIND SUCH A THEORY, AND IF SO, WHAT COULD BE THE CONSEQUENCES?

I think it's an open question as to whether we will find a complete unified theory. All I can say is that we don't seem to have one at the moment.

*END

SLATE

YOU WERE SAYING THAT THERE MAYBE SUCH A THING . . .

We may never find a complete unified theory, but I think that there is a 50-50 chance that we'll do so by the end of the century.

WHAT WOULD BE THE CONSEQUENCES OF SUCH A THEORY? WOULD WE THEN KNOW EVERYTHING THERE IS TO KNOW ABOUT PHYSICAL REALITY?

In principle, but not in practice. Because the equations are very difficult to solve in any but the simplest situations. We already know the laws of physics that underlie the behaviour of matter in normal circumstances. So in principle, we should be able to predict all of physics, all of chemistry and biology. But we've not had much success in predicting human behaviour from mathematical equations.

SO LIFE WILL STILL BE FULL OF SURPRISES?

Yes, in principle we should be able to predict everything. But in practice it won't make any difference. We already know the laws of physics which govern this matter except in circumstances as extreme as the beginning of the early stages of the universe.

YOU LIVE IN A WORLD THAT APPEARS TO BE VERY ESOTERIC AND DISTANT AND ABSTRACT FROM THE ORDINARY MAN-IN-THE-STREET, EVEN TO YOUR WIFE. DO YOU EVER GET FRUSTRATED BY THE DIFFICULTIES IN COMMUNICATING THE NATURE OF YOUR WORK?

I believe most people have an interest in how the universe works, even though they may not have much technical knowledge. But I think in principle it should be easy to explain the basic ideas.

HOW ABOUT IN PRACTICE, DOES IT EVER FRUSTRATE YOU?

I do my best, and I do think I have some success.

YOU ARE QUITE ACTIVE ON BEHALF OF DISABLED PEOPLE IN OBTAINING GRANTS. WHAT ATTITUDE DO YOU TAKE TO YOUR OWN DISABILITY?

It is a bit of an inconvenience. But it has not really prevented me from doing what I want to do in life. In a way, it has made me appreciate much more . . . I've been much fortunate in being able to carry on. And that is really due to all the help that I've had from my family and colleagues.

HAD YOU NOT BEEN DISABLED, WOULD YOU HAVE BEEN INVOLVED IN THE SAME BRANCH OF PHYSICS?

If I had not been disabled, then certain things would have been easier. Like reading books or writing down equations. But on the other hand, I would have had to spend more time lecturing and setting examinations. So, all in all, I don't think it has made much difference to the amount of work that I would have been able to do. If it has had any effect at all, it has probably affected the kind of work I do. Because I think I'd probably have worked with problems involving a lot of equations. And if I had not been disabled, I might have done a lot more work in problems which required a great deal of equations.

YOU SAID THAT WHEN YOU FIRST FOUND OUT YOU HAD YOUR DISEASE IT WAS VERY DIFFICULT, THAT YOU BECAME QUITE FULL OF DESPAIR AND QUITE BITTER. COULD YOU TELL ME A LITTLE BIT ABOUT THAT PERIOD?

I don't think I became bitter. But I was certainly depressed. I didn't at the time think there was much point in completing my Ph.D. because my life expectency was so short.

HOW DID IT CHANGE FOR YOU?

SLATE

The disease progressed rapidly at first. But then it seemed to slow down. And around the same time I began to fully understand the problem I was working on. But what really made a difference was that I became engaged to Jane. That meant that if I was going to get married, I'd have to get a job. And if I was going to get a job, I'd have to write some papers. So that really started me working. And I've been at it every since.

BECAUSE OF YOUR ILLNESS, ARE YOU IN A RACE AGAINST TIME?

Not really, in a sense all theoretical physicists are in a race against time. Because as they get older, it's rather harder to do theoretical physics. My supervisor, Dennis Yama, had a party when he was 30 to celebrate his retirement as a theoretical physicist. But in fact his best work came after that.

JUST GOES TO SHOW YOU . . .

I'm now 43, and generally considered a bit overhill for a theoretical physicist.

YOU SEEM TO BE HOLDING UP OKAY. YOUR SCIENCE IS MORALLY NEUTRAL. WHAT ISSUES SHOULD SCIENTISTS TODAY BE SPEAKING OUT ABOUT?

I think that science itself is morally neutral. But scientists themselves need not be morally neutral. They are human beings like everyone else. They have moral responsibilities.

WHAT ISSUES THEN SHOULD SCIENTISTS BE TALKING ABOUT?

All issues, but particularly those like nuclear warfare. Which involve a complicated set of equations. I think questions such as nuclear war, which involve an awful lot of complicated questions which most people cannot judge for themselves.

...HAVE WRITTEN ABOUT YOU IN WAYS THAT ALMOST IMPLIES YOU'RE LIKE A COMPLETE CERBO BEING. THAT YOU DON'T HAVE AN EMOTIONAL LIFE . . .

That is completely untrue. I don't live for science alone. Science is very important to me, but it is not enough. In fact if that's all I had, then my life would be very empty. I'm very lucky that I have my family. They are very important to me.

ARE THEY A SOURCE OF JOY?

Oh yes.

CUT FOR SYNCH

CNN Interview Transcript
Larry King Live Weekend
Stephen Hawking Discusses Quantum Physics and ALS
Aired December 25, 1999 - 9:00 p.m. ET
THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

LARRY KING, HOST: Tonight, an incredible man, an amazing intellect. It's been said that he can sell physics better than Madonna can sell sex. We're honored to have Professor Stephen Hawking with us for the full hour. It's all next on LARRY KING LIVE.

Welcome.

The words brilliant and genius probably get used way too much. But my guest tonight deserves both of them and more. Professor Stephen William Hawking is an intellectual icon, best selling author, the greatest mind in physics since Albert Einstein. A couple of notes about what you're going to see and hear. We traveled to Cambridge University in England to talk to Professor Hawking. The first interview was so fascinating we wanted more and our guest was gracious enough to agree.

As you probably know, Stephen Hawking suffers from a disease known as ALS. While he thinks in a lot more dimensions than most of us, he's wheelchair bound and uses a voice synthesizer to talk.

Operating that synthesizer isn't an instant kind of thing. So we gave Professor Hawking our questions in advance. There were some long pauses in the interview and we have cut them out.

But we've kept every word from Stephen Hawking because the man who says he aims to understand the universe, why it is the way it is, why it exists at all is someone you don't want to edit.

(BEGIN VIDEOTAPE)

As a scientist, what would you say, professor, has been your biggest accomplishment?

PROFESSOR STEPHEN HAWKING, CAMBRIDGE UNIVERSITY: I am glad to have advanced our understanding of the big bang and black holes, the beginning and end of time. I almost said to have shed light on black holes but maybe that is the wrong metaphor.

KING: Did you have this gift of knowledge as a child or did you develop it? Were you a very brilliant kid?

HAWKING: All children ask questions. How do things work? Why are they the way they are? But as they grow up they get told these questions are stupid or that they don't have answers. I am just a child that has never grown up. I still keep asking these how and why questions. Occasionally I find an answer.

KING: How, professor, do you regard yourself, teacher, researcher, scientist, all the above?

HAWKING: I would describe myself as a research scientist. I don't teach or lecture to undergraduates, but I have advised about 30 graduates for their Ph.D.s and in some cases almost written the thesis for them.

KING: Did you have a mentor?

HAWKING: I have had a number of good teachers and a few not so good but none that I would call my mentor. The nearest would be Roger Penrose (ph), whose work introduced me to the big bang and black holes. But he was more a colleague and collaborator than a mentor.

KING: Why, professor, did you choose the field you chose? Why physics? Why this area of study?

HAWKING: My father was a research scientist in tropical medicine so I grew up thinking that a research scientist was a natural thing to be. But I felt biology was too vague and descriptive so I went into physics, the study of the laws that govern the universe, because it was the most fundamental of the sciences. My father was disappointed I didn't go into medicine, but was consoled when my sister did so.

KING: You have been called, Professor Hawking, the most intelligent person on earth. What's it like to hear something like that? I imagine -- do you agree with it?

HAWKING: That is media hype. Newspapers have these ridiculous lists of the hundred most something people. Recently I was listed as the second most intelligent person in Britain but the first was Richard Branson.

KING: Mr. Branson, of course, owns an airline.

(BEGIN VIDEO CLIP)

RICHARD BRANSON, CHAIRMAN, THE VIRGIN GROUP: I certainly don't consider myself more intelligent than Professor Hawkings. He is the sort of person who also doesn't take no for an answer, thinks outside the box and the difference is that he knows what's outside the box and he knows what's the other side of the universe. He can out brain anybody in Britain. He certainly can out brain myself. I left school at 15. What the hell's he talking about?

(END VIDEO CLIP)

(END VIDEOTAPE)

(COMMERCIAL BREAK)

KING: Stephen Hawking says he never was very coordinated. He had lousy handwriting when he was a kid, didn't care much for sports but he started having real physical problems, stumbling, clumsiness, while he was a graduate student at Cambridge. In 1963, he was diagnosed with ALS and he was just 21 years old. Doctors told him he probably had about two years to live and they were wrong.

(BEGIN VIDEOTAPE)

KING: ALS is the wasting disease that killed Lou Gehrig, baseball's legendary iron horse, and there's no cure for it. Not very long ago, Professor Hawking told an audience in Chicago that his greatest achievement is being alive.

HAWKING: I have ALS, a motor neuron disease. This is a condition in which the nerves controlling muscles die off but the sensory nerves continue as before. It is not supposed to affect intelligence but maybe I'm too far gone to notice. One form of ALS is linked to a defective gene, but most ALS seems to occur at random and its cause is not known.

KING: How has the disease affected your work?

HAWKING: Had I chosen almost any other career, my ALS would have ended it. But theoretical physics is all in the mind, so I was able to carry on. Obviously there are practical difficulties like handling books and papers, but I have found ways to deal with them. It is a lot easier now that everything is on computers. I can download physics papers on the Internet and don't need physical paper.

KING: Has the disease -- this is strange -- in any way been an aid to your work?

HAWKING: I can't say that my disability has helped my work but it has allowed me to concentrate on research without having to lecture or sit on boring committees.

KING: Professor, the normal life expectancy for someone with ALS is two to three years max. You've had it for 21 years. How do you explain that?

HAWKING: ALS seems to be a condition that can result from different causes. The variety I have must be different from the most common form, which kills in two or three years. Maybe my ALS is caused by bad absorption of vitamins. My wife says I'm an alien in the morning before I have my vitamins.

KING: What, professor, is your daily life like?

HAWKING: I lead a reasonably normal life but I need help with most things and the routines like getting up or eating take me longer. I am very fortunate in the help I receive from my wife and lucky that I can afford nurses to assist me.

KING: How do you deal with the inevitability that one day you will lose your ability to communicate?

HAWKING: We all face the inevitability of death one day. While I am alive, I will make sure I communicate one way or another.

(END VIDEOTAPE)

KING: When Stephen Hawking says he will communicate, you've got to believe him. A pneumonia nearly suffocated him in 1985. Doctors did a procedure that let him breathe through an opening in his throat and a tube put into his trachea. His life was saved but his voice was lost. Still, as you've heard, the man speaks.

(BEGIN VIDEO CLIP)

HAWKING: For a time, I could communicate only by raising my eyebrows when someone pointed to letters on an alphabet card. This is pretty slow and limiting. I couldn't hold a conversation and I certainly couldn't write a scientific paper. Fortunately, I have enough movement in my hands that I can press and release a single switch in my hand quite rapidly. This is used to control a computer program in which a cursor moves down the screen and then across. In this way, I can select words from lists on the screen. The words I have chosen are printed on the lower half of the screen. When I have built up what I want to say, I can send it to a speech synthesizer.

The synthesizer I use is 13 years old but I stick to it partly because I now identify with it and partly because it doesn't speak in a monotone but varies the intonation in an almost human way. It is very important that those who have to use artificial speech should have a voice they can identify with and feel happy with. No one wants to sound like a machine or Mickey Mouse.

With the computer program I use, I can manage 10 to 15 words a minute. By contrast, normal speech is 120 to 180 words a minute. This means that for speeches and lectures I have to write them in advance, save them on disk and then send them to the speech synthesizer sentence by sentence. It is possible that a different computer program might be slightly faster, but there is a basic limit to the rate that information can be transmitted by pressing a single switch.

In computer terms, I have a baud rate of about three that responds to the information in about 20 words a minute. By contrast, a political speech has a word rate of about 150 and an information content of zero.

(END VIDEO CLIP)

KING: It may take Hawking as much as 40 hours to prepare a 45 minute lecture. By the way, some people think the synthesizer sounds Scandinavian. Hawking sometimes jokes about his computer's American accent. We'll be back with more.

(COMMERCIAL BREAK)

KING: Welcome back.

Stephen Hawking was born January 8th, 1942, 300 years to the day of the death of the astronomer Galileo. Even when he was a little boy, he wanted to figure out how the world worked. He says that he loved taking stuff apart. Unfortunately, he wasn't very good at getting it back together.

In 1962, Hawking earned an undergraduate degree with first class honors from Oxford and then headed to Cambridge to study cosmology. He stayed on there after receiving his Ph.D. Hawking has wracked up all kinds of honors, including a dozen honorary degrees. He's also received the most prestigious prize in theoretical physics. It's named after the man Hawking calls the best scientific mind of the century.

(BEGIN VIDEO CLIP)

HAWKING: Undoubtedly the greatest scientific figure of the century is Albert Einstein. He revolutionized our ideas of space and time with his general theory of relativity. It is said that space and time are not just a fixed background in which events take place but that they are curved and warped by the matter and energy in the universe. We are still working out the implications of general relativity.

After Einstein, I would rank people Werner Heisenberg, Irwin Schroedinger and Paul Dirac, who developed quantum theory, the other major advance this century. It changed our picture of the universe and of reality itself. When we have found out how to combine these theories we will understand how the universe began, is evolving, and will end.

(END VIDEO CLIP)

KING: Since 1979, Hawking has been the Lukesian (ph) professor of mathematics at Cambridge. Sir Isaac Newton, the man who discovered gravity, held that same post three centuries ago.

(BEGIN VIDEOTAPE)

KING: Did you ever want to be anything besides a research scientist? Did your incredible intelligence in any way make you feel like you had to go into science for the betterment of man regardless of your own personal dreams?

HAWKING: Before I got ALS I considered a number of other careers including being a political leader. Because I wasn't born in the U.S., I couldn't be president but I might have been British prime minister. However, I'm glad I left that job to Tony Blair. I think I get more job satisfaction than he does and I expect my work will last longer.

KING: Did you ever consider changing direction when you got ALS and focus on taking that mind of yours and finding a cure for it?

HAWKING: I don't think I would be much good at research on ALS and I wouldn't want to engage in it even if I could. I am happy to follow research from a distance but I want to get on with a fairly normal life and forget about ALS.

KING: What did you think of the movie "Good Will Hunting?" Could you associate with the lead character, a kind of genius? HAWKING: I was very encouraged to see a film about real intellectual struggle but I wasn't convinced by the central character. She seemed to regard the discoveries she made as just mathematical tricks and didn't get pleasure from them. In my experience, when you discover something that no one knew before that is the most wonderful feeling in the world. It is like sex but it lasts longer.

KING: One could only imagine what that's like. You said before there was a 50-50 percent chance that your string theory would be proven out by the end of this century. How's that coming and for definition, what is the string theory?

HAWKING: In 1980, I said I thought there was a 50-50 chance we would find a complete unified theory within the next 20 years. String theory would be one aspect of that unified theory. Although we have made a lot of progress since then, we don't yet have a complete unified theory of the universe. Nevertheless, I still think there's a 50-50 chance we will find a complete unified theory in the next 20 years. But that 20 years starts now.

KING: Helping in the quest for a unified theory, a super computer called Cosmos. It lives at Cambridge University. Its task? Nothing less than tracing the origins of the universe. Talk about looking way back. Scientists figure the universe is about 15 billion years old.

HAWKING: I think everyone wants to know where we came from and how the universe began. Cosmos can help us find answers to those questions. Hopefully, when we understand how the universe began it will give us a clue as to why it began the way it did or even why it began at all.

(END VIDEOTAPE)

(COMMERCIAL BREAK)

(BEGIN VIDEOTAPE)

KING: Is there anywhere, professor, in the world that you have not been that you would like to go and why?

HAWKING: Where I would really like to go is not anywhere on earth but out in space. If I were someone like Bill Gates I would hire the space shuttle. It would only cost a few hundred million dollars.

KING: What advice would you give an intelligent, open-minded young man or woman contemplating a future career? Would you recommend science and research? If you had to start all over again in the year 2000, would you choose what you've chosen?

HAWKING: I think science and research are more satisfying than just making money. But if I were starting now, I might choose molecular biology rather than cosmology. We may find the basic laws that govern the universe but we will never exhaust the complexity of possible biological systems. KING: What, Professor Hawking, do you consider the most important discovery of this millennium?

HAWKING: I think the invention of printing was a breakthrough for the human race. It meant that information and discoveries could be disseminated widely and not just on a one to one basis by word of mouth or handwritten manuscript. It led to an ever increasing rate of scientific and technological development. This has now made printing almost obsolete and replaced it by the Internet.

KING: What do you expect will be the biggest change in the way we'll live in the future?

HAWKING: I think genetic engineering with humans is going to occur whether we like it or not. It will change our standard of what is human but it will be a gradual change because there's so much we don't know and because humans take time to grow up. We won't change much in the next 100 years but we might after that.

KING: Professor, where will you be, what will you be doing on, at midnight on December 31st?

HAWKING: We are having a Simpsons fancy dress party. People are coming as Springfield characters. The great thing is I can go as myself.

(BEGIN VIDEO CLIP, "THE SIMPSONS")

HAWKING: I don't know which is the bigger disappointment, my failure to formulate a unified field theory or you.

DAN CASTELLANETA, ACTOR: I don't like your tone.

HAWKING: If you are looking for trouble, you've found it.

CASTELLANETA: Yeah, just try me you -- oh. The guns are openers. Come on, you idiots. We're taking back this town.

HAWKING: Time for this hawk to fly. Wrong button.

CASTELLANETA: Did you have fun with your robot, buddy?

YEARDLY SMITH, ACRTRESS: Dad! Oh, Dr. Hawking, we had such a beautiful dream. What went wrong?

HAWKING: Don't feel bad, Lisa. Sometimes the smartest of us can be the most childish.

SMITH: Even you?

HAWKING: No, not me. Never.

(END VIDEO CLIP)

(END VIDEOTAPE)

(COMMERCIAL BREAK)

KING: Stephen Hawking has written extensively in the field of theoretical physics, most of his work is highly technical. Intellectual heavy lifting to say the least. But in 1988 he wrote the book "A Brief History of Time".

(BEGIN VIDEO CLIP)

HAWKING: My original aim was to write a book that would sell on airport book stalls. But for that, maybe the publisher should have put a naked woman rather than me on the cover.

MARK BARTY-KING, PUBLISHER: Stephen always saw this book as being a great mass market book. And I think publishers found that quite difficult to assess at beginning, because it was, you know, a very difficult book, and very much a science book. And it was probably one of the first science books that ever broke out into the mass market, in the way that Stephen had predicted.

HAWKING: All over the world, people come up to me and say how much they have enjoyed my book. They may not have understood it all. If they did, they would be ready to start a Ph.D. in theoretical physics. But they have got a feeling of being in touch with the big questions: Where did we come from, and how did it all begin?

BARTY-KING: I certainly couldn't understand the book, and, however, I did read it with some enjoyment, always expecting to be able to understand it. And it was so lucidly written it was actually a pleasure -- a pleasure to read. But we didn't -- we didn't know that this book was going to break out in the way that it did. We started with a very small printing of, I think, 5,000 copies.

(END VIDEO CLIP)

KING: "A Brief History" practically took up residence on the best-seller list when it came out. It's been translated into some 30 languages and sold about 10 million copies worldwide.

(BEGIN VIDEO CLIP)

BARTY-KING: Whether Stephen is contemplating a sequel if any kind at this point, I don't know, but it would be nice if he was.

(END VIDEO CLIP)

KING: A sequel to "Brief History?" Who knows. But the book did inspire a movie, and we'll show you highlights from it later. All this has made Hawking something of a media darling and a commercial hit.

(BEGIN VIDEOTAPE)

(BEGIN VIDEO CLIP, "SPACEAVERS OPTICANA COMMERCIAL")

HAWKING: I had always spoke to see this in my lifetime. I have been wondering about the mysteries of the universe since I was a child. Yet, looking at the beauty of these things still fills me with wonder. For me, physics is about seeing further, better, and deeper. And from here, I can see forever.

(END VIDEO CLIP)

KING: What, Professor, is cosmology?

HAWKING: Cosmology is the study of the whole universe, its origin, evolution, and eventual fate. It is a background to all our lives.

KING: What, in your area of study, Stephen, do we know the least about?

HAWKING: We feel we are tantalizingly close to a complete Unified Theory, but we might be miles away or barking up the wrong tree. If I had a wish, it would be to know whether we are on the right track.

KING: What is a black hole?

HAWKING: A black hole is a region that is so warped by gravity that light cannot get out. Or at least people thought that light could not get out of a black hole, until I showed that the Uncertainty Principle of quantum mechanics allows light to leak out slowly. Some people call this Hawking Radiation.

KING: When, Professor, did the universe begin, and do you know when it'll end?

HAWKING: We have good evidence the universe began in a big bang, about 15 billion years ago. We are less certain how it will end, but recent observations suggest a universe will expand forever at an ever- increasing rate.

KING: Do you believe in life in other places, other planets?

HAWKING: Life appeared on earth fairly soon after the earth was formed, 4.5 billion years ago. That suggests that primitive life will appear spontaneously on any suitable planet. On the other hand, intelligent life seems very rare. It has yet to be detected on earth.

KING: Do you believe in a sixth sense, a spirit world, another level of existence?

HAWKING: I do not believe in a sixth sense, if you mean extrasensory perception. That would not be consistent with my belief that a universe is governed by a mathematical laws. Spiritual values belong to a different category to the physical universe.

KING: Do you believe in God?

HAWKING: Yes, I do, if by God you mean the embodiment of the laws that govern the universe.

(BEGIN VIDEO CLIP, "A BRIEF HISTORY OF TIME") HAWKING: If you were watching an astronaut foolhardy enough to jump into a black hole, at some time on his watch, say 12:00, he would cross the event horizon and enter the black hole. But no matter how long you waited, you would never see the astronaut's watch reach 12:00. Instead, each second on the watch would appear to take longer and longer, until the last second before midnight would take forever. The astronaut wouldn't notice anything special when his watch reached midnight, and he crossed the event horizon into the black hole, until, of course, he approached the singularity and was crushed into spaghetti.

(END VIDEO CLIP)

(END VIDEOTAPE)

(COMMERCIAL BREAK)

(BEGIN VIDEOTAPE)

(BEGIN VIDEO CLIP, "A BRIEF HISTORY OF TIME")

HAWKING: Einstein never accepted quantum mechanics because of its element of chance and uncertainty. He said, "God does not play dice." It seems that Einstein was doubly wrong. The quantum affects of black holes suggest that not only does God play dice, He sometimes throws them where they cannot be seen.

(END VIDEO CLIP)

KING: What, Professor, puzzles you the most? What do you think about the most?

HAWKING: Women.

KING: Welcome aboard. Are you optimistic or pessimistic about the future?

HAWKING: I see great danger for the future. But I'm an optimist. I expect we will find a way forward.

KING: What do you think is the biggest challenge that we have to overcome?

HAWKING: I think the biggest challenge we face is from our aggressive instincts. In caveman -- or caveperson days, these gave definite survival advantages and were imprinted in our genetic code by Darwinian natural selection. But with nuclear weapons, they threaten our destruction. We don't have time for Darwinian evolution to remove our aggression. We will have to use genetic engineering.

KING: What's your biggest worry for society?

HAWKING: My biggest worry is population growth. If it continues at the current rate, we will be standing shoulder to shoulder by 2600. Something has to happen, and I don't want it to be a disaster.

KING: Do you think we'll ever cure disease?

HAWKING: We are already able to cure most diseases of the past. But unless we become immortal, we are bound to die of something. We can extend our lives, but it is probably more important to improve the quality while we are alive.

(END VIDEOTAPE)

KING: As you heard a minute ago, Professor Hawking is deeply concerned the world is getting overcrowded. What about the possibility that it's getting overheated, too? His thoughts, now, on global warming.

(BEGIN VIDEOTAPE)

HAWKING: The temperature of the earth has gone up and down in history, so one might argue that a recent warming was just a natural fluctuation. But there is no question that the level of carbon dioxide in the atmosphere is now far higher than it has ever been in the past.

Carbon dioxide is produced when we burn coal, oil, or gas. It is what is called a greenhouse gas. That is, it let's in heat from the sun, but makes it difficult for the heat to escape again. So the large amount of carbon dioxide now in the atmosphere will inevitably cause global warming. How much the warming will be, we don't know.

If it were only a few degrees, that would be serious, but we could adapt to it. But the danger is the warming process might be unstable and run away. We could end up like Venus, covered in clouds and with the surface temperature of 400 degrees.

It could be too late if we wait until the bad effects of warming become obvious. We need action now to reduce emission of carbon dioxide. And that action must include the U.S., since you have by far, the highest emission per head.

(END VIDEOTAPE)

(COMMERCIAL BREAK)

(BEGIN VIDEOTAPE)

(BEGIN VIDEO CLIP, "STAR TREK: THE NEXT GENERATION")

HAWKING: ... but then I said "In that frame of reference, the perihelion of Mercury would have recessed in the opposite direction."

UNIDENTIFIED ACTOR: That is a great story.

BRENT SPINER, ACTOR: Quite amusing, Dr. Hawking.

You see, Sir Isaac, the joke depends on an understanding of the relativistic curvature of space-time. If two non-inertial reference frames are in relative motion... UNIDENTIFIED ACTOR: Do not patronize me, sir. I invented physics. The day that apple fell on my head was the most momentous day in the history of science.

HAWKING: Not the apple story again.

UNIDENTIFIED ACTOR: It's your bet.

HAWKING: I raise $50.

UNIDENTIFIED ACTOR: All the quantum fluctuations in the universe will not change the cards in your hand. I call.

UNIDENTIFIED ACTOR: You are bluffing.

UNIDENTIFIED ACTOR: And you will lose.

HAWKING: Wrong again, Albert.

UNIDENTIFIED ACTOR: Well...

JONATHAN FRAKES, ACTOR: Red alert. All personnel report to duty stations.

SPINER: We will have to continue this another time. End program.

(END VIDEO CLIP)

KING: Well, we all watched "Star Trek," and you have worked with time and travel and the like. Do you think we'll ever travel from Britain to Japan in an hour?

HAWKING: Britain to Japan in an hour is quite possible. But to do it in half an hour would require more than orbital velocity, and would be very difficult. You would need a rocket to hold you down to earth.

KING: Do you like science fiction, Professor? Can it be harmful, or helpful, or neither?

HAWKING: I think science fiction is useful, both for stimulating the imagination and for defusing fear of the future. But science fact can be even more amazing. Science fiction never suggested anything as strange as black holes.

KING: Professor, do you believe in the concept of time travel?

HAWKING: Time travel seems to be allowed by Einstein's General Theory of Relativity in certain situations, but if you combine General Relativity with Quantum Theory, it looks like you would be wiped out by a bolt of radiation before you could travel into the past. We certainly haven't seen any tourists from the future.

KING: Where do you believe that our research dollars -- and we have plenty of them -- would be best spent? HAWKING: There isn't a single answer to that question. There are a whole range of projects in different fields. In my own field of physics, I would say more satellites to observe the universe about the atmosphere. And something to replace the SSC Particle Accelerator that was being built in Texas, but which was canceled in 1994 when the U.S. went through a fit of feeling poor.

KING: Professor, what do you think of the Y2K bug? Are you worried what's going to happen on January 1st?

HAWKING: I think the Y2K bug has been exaggerated. I expect January the 1st, 2000, to be a great anticlimax. A few things will go wrong, but it won't be the end of the world if ATM machines don't work.

KING: Do you surf the net? What do you think of this Internet thing?

HAWKING: I use the Internet each day to get physics papers and to get the news from the BBC or CNN. But I regard surfing the net as as mindless as channel hopping on television.

KING: What is the most intelligent person in the world do for fun?

HAWKING: I have told you it's ridiculous to call me the most intelligent person. And what I do for fun is private.

(END VIDEOTAPE)

KING: We respect the professor's privacy, of course. Still we managed to have him tell us what kind of music he likes.

(BEGIN VIDEOTAPE)

HAWKING: It was in 1963 that I first developed an interest in Wagner, or Wagner, as my speech synthesizer pronounces him. I had just been diagnosed as having ALS, or Motor Neuro Disease. and given a distinct impression I didn't have long to live. I regarded Wagner as music that was dark enough for my mood. My mother bought me tickets to go to the Wagner festival at Bayreuth in Germany, and I went with my sister, Philippa. It was magic. His personal use and conduct were pretty objectionable. But his music, though sometimes pompous and long-winded, reaches a level no one else does.

(END VIDEOTAPE)

(COMMERCIAL BREAK)

KING: Welcome back.

We've shown you many sides of Professor Stephen Hawking. One you haven't seen yet is Stephen Hawking the sports fan. Well, fan of one sport, anyway.

(BEGIN VIDEOTAPE) HAWKING: My younger son, Tim, is very keen in Formula One racing, and it's an interest I can share with him. We know Frank Williams, who runs the Williams Team, and who is in a wheelchair like me. We have watched several races from the Williams pits. It is exciting to see behind the scenes, but the noise is terrific.

KING: You have three children, Professor. Did they have the best science fair projects in school? What are the kids doing now?

HAWKING: Only my eldest son, Robert, was interested in science. He's now a software engineer with Microsoft in Seattle. My daughter, Lucy, studied French and Russian, and is now a journalist. My younger son, Tim, is at university doing French and Spanish. And I have a grandson, William, who is learning to talk and is fascinated by computers.

KING: You mentioned earlier we'll all die of something. Do you think you can live another 30, 40 years with this disease? Do you think this disease might be cured?

HAWKING: I don't look too far ahead, but I'm now thinking of my 60th birthday in 2002. I don't expect to be cured of ALS. It will be enough if it just doesn't get worse.

KING: What keeps you going? We all can see and are aware of your condition and how well you deal with it. What is that inner thing that keeps you going?

HAWKING: Curiosity. I want to know the answers. I enjoy life. I will keep going as long as I can. What else can anyone do?

KING: And finally, happiness is relative, of course. Are you a happy man?

HAWKING: Yes.

KING: Thank you, Professor.

What an hour.

(BEGIN VIDEO CLIP, "A BRIEF HISTORY OF TIME")

HAWKING: If we do discover a complete theory of the universe, it should in time be understandable in broad principle by everyone, not just a few scientists. Then we shall all -- philosophers, scientists and just ordinary people -- be able to take part in the discussion of why it is that we and the universe exist. If we find the answer to that, it would be the ultimate triumph of human reason. For then, we would know the mind of God.

(END VIDEO CLIP)

(END VIDEOTAPE)