This means that at earlier times objects would have been closer together. In fact, it seemed that there was a time, about ten or twenty thousand million years ago, when they were all at exactly the same place and when, therefore, the density of the universe was infinite.

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

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Nothing cannot exist forever.

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I'm happy if I have added something to our understanding of the universe.

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Intelligence is the ability to adapt to change.

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The basic assumption of science is scientific determinism.

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It is all right to make mistakes; nothing is perfect because with perfection, we would not exist.

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The thing about smart people is that they seem like crazy people to dumb people.

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The twentieth century saw man's view of the universe transformed: we realized the insignificance of our planet in the vastness of the universe, and we discovered that time and space we curved and inseparable , that the universe was expanding, and that it had a beginning in time.

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I've noticed that even people who believe in fate look both ways before crossing the street.

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