Quotes from Stephen Hawking

One way or another, I regard it as almost inevitable that either a nuclear confrontation or environmental catastrophe will cripple the Earth at some point in the next 1,000 years

How do we know that we are not just characters in a computer-generated soap opera?

In conclusion, rapid space travel and travel back in time can't be ruled out according to our present understanding. They would cause great logical problems, so let's hope there's a Chronology Protection Law to prevent people going back and killing their parents.

And at the end of all this, the fact that we humans, who are ourselves mere collections of fundamental particles of nature, have been able to come to an understanding of the laws governing us, and our universe, is a great triumph. I want to share my excitement about these big questions and my enthusiasm about this quest.

If the boundary condition of the universe is that it has no boundary in imaginary time, it won't have just a single history. There are many histories in imaginary time and each of them will determine a history in real time. Thus we have a superabundance of histories for the universe. What picks out the particular history, or set of histories that we live in, from the set of all possible histories of the universe?

Personally, I get uneasy when people, especially theoretical physicists, talk about consciousness. Consciousness is not a quality that one can measure from the outside. If a little green man were to appear on our doorstep tomorrow, we do not have a way of telling if he was conscious and self-aware or was just a robot.

The lack of an absolute standard of rest meant that one could not determine whether two events that took place at different times occurred in the same position in space. For example, suppose our Ping-Pong ball on the train bounces straight up and down, hitting the table twice on the same spot one second apart. To someone on the track, the two bounces would seem to take place about thirteen meters apart, because the tram would have traveled that far down the track between the bounces.

We really don't care how many histories there may be that don't contain intelligent beings. We are interested only in the subset of histories in which intelligent life develops. This intelligent life need not be anything like humans. Little green men would do as well. In fact, they might do rather better. The human race does not have a very good record of intelligent behaviour.

I would like to speculate a little on the development of life in the universe, and in particular on the development of intelligent life. I shall take this to include the human race, even though much of its behaviour throughout history has been pretty stupid and not calculated to aid the survival of the species. Two questions I shall discuss are "What is the probability of life existing elsewhere in the universe?" and "How may life develop in the future?

THE ORIGIN OF THE UNIVERSE

An asteroid collision would be something against which we have no defence. The last big such collision with us was about sixty-six million years ago and that is thought to have killed the dinosaurs, and it will happen again. This is not science fiction; it is guaranteed by the laws of physics and probability.

Eine große Offenbarung des Weltraumzeitalters bestand darin, dass es der Menschheit die Sicht auf sich selbst ermöglichte. Betrachten wir die Erde vom All aus, sehen wir uns selbst als Ganzes. Wir nehmen die Einheit wahr und nicht das Trennende. Ein einfaches Bild mit einer unwiderlegbaren Botschaft: ein Planet, eine Menschheit.

Segundo algumas teorias, o universo que vivenciamos é apenas uma superfície quadridimensional em um espaço com dez ou onze dimensões. O filme Interestelar dá uma ideia de como isso funcionaria. Nós não veríamos essas dimensões extras porque a luz não se propagaria por elas, mas apenas pelas quatro dimensões do nosso universo.

This intelligent life need not be anything like humans. Little green men would do as well. In fact, they might do rather better. The human race does not have a very good record of intelligent behaviour.

One way or another, I regard it as almost inevitable that either a nuclear confrontation or environmental catastrophe will cripple the Earth at some point in the next 1,000 years which, as geological time goes, is the mere blink of an eye. By then I hope and believe that our ingenious race will have found a way to slip the surly bonds of Earth and will therefore survive the disaster.

Einstein never accepted that the universe was governed by chance; his feelings were summed up in his famous statement, 'God does not play dice.' Most other scientists, however, were willing to accept quantum mechanics because it agreed perfectly with experiment.

from ourselves. I am convinced that humans need to leave Earth. If we stay, we risk being annihilated.

Como veremos, o conceito de tempo não tem significado antes do início do universo. Isso foi observado pela primeira vez por santo Agostinho. Quando lhe perguntavam "O que Deus fazia antes de criar o universo?", sua resposta não era "Ele estava preparando o inferno para pessoas que fizessem perguntas como essa". Em vez disso, respondia que o tempo era uma propriedade do universo criada por Deus e não existia antes dele. Quando

All the evidence points to God being an inveterate gambler, who throws the dice on every possible occasion.

The basic assumption of science is scientific determinism.

It is said that fact is sometimes stranger than fiction, and nowhere is that more true than in the case of black holes. Black holes are stranger than anything dreamed up by science-fiction writers, but they are firmly matters of science fact.

The laws of science determine the evolution of the universe, given its state at one time.

Estoy convencido de que los humanos necesitamos dejar la Tierra para evitar correr el riesgo de ser aniquilados.

Many people through the ages have attributed to God the beauty and complexity of nature that in their time seemed to have no scientific explanation. But just as Darwin and Wallace explained how the apparently miraculous design of living forms could appear without intervention by a supreme being, the multiverse concept can explain the fine-tuning of physical law without the need for a benevolent creator who made the universe for our benefit.