It is like a drinking straw. The surface of a straw is two-dimensional. However, one direction is curled up into a small circle, so that from a distance the straw looks like a one-dimensional line.

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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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Nothing is better than reading and gaining more and more knowledge.

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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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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.

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Quiet people have the loudest minds.

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I used to think information was destroyed in black hole. This was my biggest blunder, or at least my biggest blunder in science.

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We are all now connected by the Internet, like neurons in a giant brain.

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Teori relativitas umum Einstein menyiratkan bahwa alam semesta harus punya permulaan dan, mungkin akhir.

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How difficult life may seem, while there’s life, there is hope.

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