100 years ago, Einstein's theory of relativity shattered the world of physics. Our comforting Newtonian ideas of space and time were replaced by bizarre and counterintuitive conclusions: if you move at high speed, time slows down, space squashes up and you get heavier; travel fast enough and you could weigh as much as a jumbo jet, be squashed thinner than a CD without feeling a thing - and live for ever. And that was just the Special Theory. With the General Theory came even stranger ideas of curved space-time, and changed our understanding of gravity and the cosmos. This authoritative and entertaining Very Short Introduction makes the theory of relativity accessible and understandable. Using very little mathematics, Russell Stannard explains the important concepts of relativity, from E=mc2 to black holes, and explores the theory's impact on science and on our understanding of the universe.
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因为现代的教学方法就像一株脆弱不堪的幼苗,除了鼓励,更需要自由只有自由オ能挽救它,使它不至于过早地天折。我认为,使用强制手段,或给人灌输责任感,让学生增进观察和探索的乐趣,确实是犯了严重的错误。在一头猛兽不饿的时候,用鞭子强迫它不断地进食,特别是人们提供的食物还是经过千挑万选的,它肯定会逐渐厌食的。两者道理相同。
当你陪一个美丽的姑娘坐上两个小时,你会觉得好像只坐了一分钟;当你坐在炙热的火炉旁,哪怕只坐上一分钟,你会感觉好像是坐了两小时。这,就是相对论。
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