I have experimental evidence that time travel is not possible.

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You can’t get to a time before the Big Bang because there was no time before the Big Bang. We have finally found something that doesn’t have a cause, because there was no time for a cause to exist in.

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Intelligence is the ability to adapt to change.

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

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Love the neighbor. But don't get caught.

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I would see the end of physics as we know it, but now I think the wonder of discovery will continue long after I am gone. We are close to some of these answers, but we are not there yet.

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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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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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So remember to look up at the stars and not down at your feet. Try to make sense of what you see and hold on to that childlike wonder about what makes the universe exist.

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

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