Stephen Hawking (Physicist)

Many people would claim that the boundary conditions are not part of physics but belong to metaphysics or religion. They would claim that nature had complete freedom to start the universe off any way it wanted. That may be so, but it could also have made it evolve in a completely arbitrary and random manner. Yet all the evidence is that it evolves in a regular way according to certain laws.

I regard [the ] as self-evidently correct. [T.F.: Yet some don't find it evident to themselves.] Yeah, well, there are some people who spend an awful lot of time talking about the interpretation of quantum mechanics. My attitude — I would paraphrase —is that when I hear of , I reach for my gun.

— Stephen Hawking time

— Stephen Hawking religion

My goal is simple. It is a complete understanding of the universe, why it is as it is and why it exists at all.

— Stephen Hawking understanding

There ought to be something very special about the boundary conditions of the universe and what can be more special than that there is no boundary?

— Stephen Hawking universe

What I have done is to show that it is possible for the way the universe began to be determined by the laws of science. In that case, it would not be necessary to appeal to God to decide how the universe began. This doesn't prove that there is no God, only that God is not necessary.

— Stephen Hawking science

We are just an advanced breed of monkeys on a minor planet of a very average star. But we can understand the Universe. That makes us something very special.

— Stephen Hawking age

On seeing the Enterprise's warp engine while visiting the set of(where he would briefly play himself in the 1993 episode ), Hawking smiled and said: I'm working on that.

— Stephen Hawking war

For millions of years, mankind lived just like the animals. Then something happened which unleashed the power of our imagination. We learned to talk and we learned to listen. Speech has allowed the communication of ideas, enabling human beings to work together to build the impossible. Mankind's greatest achievements have come about by talking, and its greatest failures by not talking. It doesn't have to be like this. Our greatest hopes could become reality in the future. With the technology at our disposal, the possibilities are unbounded. All we need to do is make sure we keep talking.

— Stephen Hawking hope

[discussing ] These lectures have shown very clearly the difference between Roger and me. He's a Platonist and I'm a positivist. He's worried thatis in a quantum state, where it is half alive and half dead. He feels that can't correspond to reality. But that doesn't bother me. I don't demand that a theory correspond to reality because I don't know what it is. Reality is not a quality you can test with litmus paper. All I'm concerned with is that the theory should predict the results of measurements. Quantum theory does this very successfully. It predicts that the result of an observation is either that the cat is alive or that it is dead. It is like you can't be slightly pregnant: you either are or you aren't.

— Stephen Hawking success

Sowas wrong when he said, "God does not play dice." Consideration of black holes suggests, not only that God does play dice, but that he sometimes confuses us by throwing them where they can't be seen.

— Stephen Hawking time

The human race is just a chemical scum on a moderate-sized planet, orbiting around a very average star in the outer suburb of one among a hundred billion galaxies. We are so insignificant that I can't believe the whole universe exists for our benefit. That would be like saying that you would disappear if I closed my eyes.

— Stephen Hawking man

I think computer viruses should count as life ... I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image.

— Stephen Hawking life

I don't believe that the ultimate theory will come by steady work along existing lines. We need something new. We can't predict what that will be or when we will find it because if we knew that, we would have found it already! It could come in the next 20 years, but we might never find it.

— Stephen Hawking work

It is not clear that intelligence has any long-term survival value.

— Stephen Hawking intelligence

Although September 11 was horrible, it didn't threaten the survival of the human race, like nuclear weapons do.

— Stephen Hawking man

All my life, I have been fascinated by the big questions that face us, and have tried to find scientific answers to them.

— Stephen Hawking life

The world has changed far more in the past 100 years than in any other century in history. The reason is not political or economic but technological — technologies that flowed directly from advances in basic science.

— Stephen Hawking science

One might think this means that imaginary numbers are just a mathematical game having nothing to do with the real world. From the viewpoint of positivist philosophy, however, one cannot determine what is real. All one can do is find which mathematical models describe the universe we live in. It turns out that a mathematical model involving imaginary time predicts not only effects we have already observed but also effects we have not been able to measure yet nevertheless believe in for other reasons. So what is real and what is imaginary? Is the distinction just in our minds?

— Stephen Hawking philosophy

I don't think the human race will survive the next thousand years, unless we spread into space...

— Stephen Hawking man

I don't think the human race will survive the next thousand years, unless we spread into space. There are too many accidents that can befall life on a single planet. But I'm an optimist. We will reach out to the stars.

— Stephen Hawking life

We shouldn't be surprised that conditions in the universe are suitable for life, but this is not evidence that the universe was designed to allow for life. We could call order by the name of God, but it would be an impersonal God. There's not much personal about the laws of physics.

— Stephen Hawking life

[on the possibility of contact with an alien civilization] I think it would be a disaster. The extraterrestrials would probably be far in advance of us. The history of advanced races meeting more primitive people on this planet is not very happy, and they were the same species. I think we should keep our heads low.

— Stephen Hawking history

The life we have on Earth must have spontaneously generated itself. It must therefore be possible for life to generate spontaneously elsewhere in the universe.

— Stephen Hawking life

— Stephen Hawking science

I'm sorry to disappoint science fiction fans, but if information is preserved, there is no possibility of using black holes to travel to other universes. If you jump into a black hole, your mass energy will be returned to our universe but in a mangled form which contains the information about what you were like but in a state where it can not be easily recognized. It is like burning an encyclopedia. Information is not lost, if one keeps the smoke and the ashes. But it is difficult to read. In practice, it would be too difficult to re-build a macroscopic object like an encyclopedia that fell inside a black hole from information in the radiation, but the information preserving result is important for microscopic processes involving virtual black holes.

— Stephen Hawking science

is the only figure in the physical sciences with a stature that can be compared with . Newton is reported to have said "If I have seen further than other men, it is because I stood on the shoulders of giants." This remark is even more true of Einstein who stood on the shoulders of Newton. Both Newton and Einstein put forward a theory ofand a theory ofbut Einstein was able to baseon thethat had been constructed bywhile Newton had to developIt is therefore appropriate to acclaim Newton as the greatest figure inand theis his greatest achievement.

— Stephen Hawking science

I have no idea. People who boast about their IQ are losers.

— Stephen Hawking idea

Life would be tragic if it weren't funny.

— Stephen Hawking funny

I am discounting reports of UFOs. Why would they appear only to cranks and weirdos?

— Stephen Hawking weird

My expectations were reduced to zero when I was 21. Everything since then has been a bonus.

— Stephen Hawking sin

Evolution has ensured that our brains just aren't equipped to visualise 11 dimensions directly. However, from a purely mathematical point of view it's just as easy to think in 11 dimensions, as it is to think in three or four.

— Stephen Hawking men

I think that it's important for scientists to explain their work, particularly in cosmology. This now answers many questions once asked of religion.

— Stephen Hawking religion

It is a waste of time to be angry about my disability. One has to get on with life and I haven't done badly. People won't have time for you if you are always angry or complaining.

— Stephen Hawking life

Equations are just the boring part of mathematics. I attempt to see things in terms of geometry.

— Stephen Hawking art

The victim should have the right to end his life, if he wants. But I think it would be a great mistake. However bad life may seem, there is always something you can do, and succeed at. While there's life, there is hope.

— Stephen Hawking life

The danger is that global warming may become self-sustaining, if it has not done so already. The melting of the Arctic and Antarctic ice caps reduces the fraction of solar energy reflected back into space, and so increases the temperature further. Climate change may kill off the Amazon and other rain forests, and so eliminate once one of the main ways in which carbon dioxide is removed from the atmosphere. The rise in sea temperature may trigger the release of large quantities of carbon dioxide, trapped as hydrides on the ocean floor. Both these phenomena would increase the greenhouse effect, and so global warming further. We have to reverse global warming urgently, if we still can.

— Stephen Hawking war

As scientists, we understand the dangers of nuclear weapons and their devastating effects, and we are learning how human activities and technologies are affecting climate systems in ways that may forever change life on Earth. As citizens of the world, we have a duty to alert the public to the unnecessary risks that we live with every day, and to the perils we foresee if governments and societies do not take action now to render nuclear weapons obsolete and to prevent further climate change... There’s a realization that we are changing our climate for the worse. That would have catastrophic effects. Although the threat is not as dire as that of nuclear weapons right now, in the long term we are looking at a serious threat.

— Stephen Hawking life

The downside of my celebrity is that I cannot go anywhere in the world without being recognized. It is not enough for me to wear dark sunglasses and a wig. The wheelchair gives me away.

— Stephen Hawking world

I'm not religious in the normal sense. I believe the universe is governed by the laws of science. The laws may have been decreed by God, but God does not intervene to break the laws.

— Stephen Hawking science

The zero-G part was wonderful and the higher-G part was no problem. I could have gone on and on. Space, here I come!

— Stephen Hawking art

In a world that is in chaos politically, socially and environmentally, how can the human race sustain another 100 years?

— Stephen Hawking men

To confine our attention to terrestrial matters would be to limit the human spirit.

— Stephen Hawking man

There is a fundamental difference between religion, which is based on authority and science, which is based on observation and reason. Science will win, because it works.

— Stephen Hawking religion

I used to think that information was destroyed in black holes. But theled me to change my mind. This was my biggest blunder, or at least my biggest blunder in science.

— Stephen Hawking science

[Asked what he thinks about most during the day] Women. They are a complete mystery.

— Stephen Hawking men

The whole history of science has been the gradual realization that events do not happen in an arbitrary manner, but that they reflect a certain underlying order, which may or may not be divinely inspired.

— Stephen Hawking science

Someone told me that each equation I included in the book would halve the sales. I therefore resolved not to have any equations at all. In the end, however, I did put in one equation, 's famous equation, . I hope that this will not scare off half of my potential readers.

— Stephen Hawking hope

Any physical theory is always provisional, in the sense that it is only a hypothesis: you can never prove it. No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory. On the other hand, you can disprove a theory by finding even a single observation that disagrees with the predictions of the theory. As philosopher of sciencehas emphasized, a good theory is characterized by the fact that it makes a number of predictions that could in principle be disproved or falsified by observation. Each time new experiments are observed to agree with the predictions the theory survives, and our confidence in it is increased; but if ever a new observation is found to disagree, we have to abandon or modify the theory.

— Stephen Hawking science

It has certainly been true in the past that what we call intelligence and scientific discovery have conveyed a survival advantage. It is not so clear that this is still the case: our scientific discoveries may well destroy us all, and even if they don’t, a complete unified theory may not make much difference to our chances of survival. However, provided the universe has evolved in a regular way, we might expect that the reasoning abilities that natural selection has given us would be valid also in our search for a complete unified theory, and so would not lead us to the wrong conclusions.

— Stephen Hawking intelligence

Bodies like the earth are not made to move on curved orbits by a force called gravity; instead, they follow the nearest thing to a straight path in a curved space, which is called a geodesic. A geodesic is the shortest (or longest) path between two nearby points.

— Stephen Hawking art

I still believe there are grounds for cautious optimism that we may now be near the end of the search for the ultimate laws of nature.

— Stephen Hawking nature

, perhaps more than any other single person, was responsible for the birth of modern science.

— Stephen Hawking science

One could say: "The boundary condition of the universe is that it has no boundary." The universe would be completely self-contained and not affected by anything outside itself. It would neither be created nor destroyed. It would just BE.

— Stephen Hawking self

Just like a computer, we must remember things in the order in which entropy increases. This makes the second law of thermodynamics almost trivial. Disorder increases with time because we measure time in the direction in which disorder increases. You can’t have a safer bet than that!

— Stephen Hawking time

Maybe that is our mistake: maybe there are no particle positions and velocities, but only waves. It is just that we try to fit the waves to our preconceived ideas of positions and velocities.The resulting mismatch is the cause of the apparent unpredictability.

— Stephen Hawking art

Even if there is only one possible unified theory, it is just a set of rules and equations. What is it that breathes fire into the equations and makes a universe for them to describe? The usual approach of science of constructing a mathematical model cannot answer the questions of why there should be a universe for the model to describe. Why does the universe go to all the bother of existing?

— Stephen Hawking science

If we do discover a complete theory, 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 the question of why it is that we and the universe exist.

— Stephen Hawking time

could predict that themust have had a beginning.

— Stephen Hawking

To show thisproperly, I would really need a four dimensional screen. However, because of government cuts, we could manage to provide only a two dimensional screen.

— Stephen Hawking men

When I gave a lecture in Japan, I was asked not to mention the possible re-collapse of the universe, because it might affect the stock market. However, I can re-assure anyone who is nervous about their investments that it is a bit early to sell: even if the universe does come to an end, it won't be for at least twenty billion years. By that time, maybe thewill have come into effect.

— Stephen Hawking time

The Steady State theory was whatwould call a good scientific theory: it made definite predictions, which could be tested by observation, and possibly falsified. Unfortunately for the theory, they were falsified.

— Stephen Hawking good

The universe would have expanded in a smooth way from a single point. As it expanded, it would have borrowed energy from the gravitational field, to create matter. As any economist could have predicted, the result of all that borrowing, was inflation. The universe expanded and borrowed at an ever-increasing rate. Fortunately, the debt of gravitational energy will not have to be repaid until the end of the universe.

— Stephen Hawking universe

So next time someone complains that you have made a mistake, tell him that may be a good thing. Because without imperfection, neither you nor I would exist.

— Stephen Hawking time

If aliens visit us, the outcome would be much as whenlanded in America, which didn't turn out well for the Native Americans. … We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet.

— Stephen Hawking life

I believe things cannot make themselves impossible.

— Stephen Hawking believe

Look up at the stars and not down at your feet. Try to make sense of what you see, and wonder about what makes the universe exist. Be curious.

— Stephen Hawking universe

While physics and mathematics may tell us how the universe began, they are not much use in predicting human behavior because there are far too many equations to solve. I'm no better than anyone else at understanding what makes people tick, particularly women.

— Stephen Hawking women

However difficult life may seem, there is always something you can do and succeed at.

— Stephen Hawking life

Intelligence is the ability to adapt to change.

— Stephen Hawking change

I have noticed even people who claim everything is predestined, and that we can do nothing to change it, look before they cross the road.

— Stephen Hawking change

People won't have time for you if you are always angry or complaining.

— Stephen Hawking time

We are in danger of destroying ourselves by our greed and stupidity. We cannot remain looking inwards at ourselves on a small and increasingly polluted and overcrowded planet.

— Stephen Hawking war

I would like nuclear fusion to become a practical power source. It would provide an inexhaustible supply of energy, without pollution or global warming.

— Stephen Hawking war

My advice to other disabled people would be, concentrate on things your disability doesn't prevent you doing well, and don't regret the things it interferes with. Don't be disabled in spirit as well as physically.

— Stephen Hawking people

I believe alien life is quite common in the universe, although intelligent life is less so. Some say it has yet to appear on planet Earth.

— Stephen Hawking life

The past, like the future, is indefinite and exists only as a spectrum of possibilities.

— Stephen Hawking future

Life would be tragic if it weren't funny.

— Stephen Hawking funny

Stem cell research is the key to developing cures for degenerative conditions like Parkinson's and motor neuron disease from which I and many others suffer. The fact that the cells may come from embryos is not an objection, because the embryos are going to die anyway.

— Stephen Hawking man

Science is not only a disciple of reason but, also, one of romance and passion.

— Stephen Hawking romance

With genetic engineering, we will be able to increase the complexity of our DNA, and improve the human race. But it will be a slow process, because one will have to wait about 18 years to see the effect of changes to the genetic code.

— Stephen Hawking change

When one's expectations are reduced to zero, one really appreciates everything one does have.

— Stephen Hawking expectations

I think computer viruses should count as life. I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image.

— Stephen Hawking life

Time travel used to be thought of as just science fiction, but Einstein's general theory of relativity allows for the possibility that we could warp space-time so much that you could go off in a rocket and return before you set out.

— Stephen Hawking science

Although September 11 was horrible, it didn't threaten the survival of the human race, like nuclear weapons do.

— Stephen Hawking man

Scientists have become the bearers of the torch of discovery in our quest for knowledge.

— Stephen Hawking knowledge

It is generally recognised that women are better than men at languages, personal relations and multi-tasking, but less good at map-reading and spatial awareness. It is therefore not unreasonable to suppose that women might be less good at mathematics and physics.

— Stephen Hawking war

Success in creating AI would be the biggest event in human history. Unfortunately, it might also be the last, unless we learn how to avoid the risks.

— Stephen Hawking history

In my school, the brightest boys did math and physics, the less bright did physics and chemistry, and the least bright did biology. I wanted to do math and physics, but my father made me do chemistry because he thought there would be no jobs for mathematicians.

— Stephen Hawking thought

One is always a long way from solving a problem until one actually has the answer.

— Stephen Hawking

Look up at the stars and not down at your feet. Be curious.

— Stephen Hawking stars

Without imperfection, neither you nor I would exist.

— Stephen Hawking perfection

Quiet people have the loudest minds.

— Stephen Hawking people

The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.

— Stephen Hawking knowledge

I have hardly ever known a mathematician who was able to reason.Plato, The Republic, Book VII, 531-E.

— Stephen Hawking book

— Stephen Hawking intelligence

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