公共英語(yǔ)PETS二級(jí)閱讀復(fù)習(xí)(3)

　　In 1971, after Einstein's death, two scientists were able to carry out a crucial experiment. They used two atomic clocks, synchronized them, and placed one on a plane, while the other stayed in the same location on Earth. The plane then flew around the world for 80 hours. According to Einstein's theory, the clock on the plane would be expected to have lost time, due to being in motion over 80 hours compared to the clock on the ground. When they brought the clocks together and made a comparison, the clock on the plane was indeed a few nanoseconds slower than the other clock.

　　愛(ài)因斯坦去世后，1971年，兩名科學(xué)家完成了一項(xiàng)重要實(shí)驗(yàn)。他們使用兩個(gè)原子鐘，將時(shí)間調(diào)成一致。其中一個(gè)被放在飛機(jī)上，而另一個(gè)則置于地球上的原來(lái)地方。隨后飛機(jī)環(huán)繞全球飛行了80個(gè)小時(shí)。按照愛(ài)因斯坦理論，相對(duì)于地面上的時(shí)鐘，飛機(jī)上的時(shí)鐘會(huì)因?yàn)?0個(gè)小時(shí)的運(yùn)動(dòng)而減少時(shí)間。當(dāng)他們將兩個(gè)時(shí)鐘拿到一起比較時(shí)，飛機(jī)上的時(shí)鐘確實(shí)較另一只慢了幾毫微秒。

　　公共英語(yǔ)PETS二級(jí)閱讀復(fù)習(xí)(4)

　　Time travel is clearly a trickier proposition than space travel, though. Put simply, Einstein's idea was that every object in the universe has it's own “time”, and these vary as objects move. The faster an object moves, the slower its time is, compared to the time of a slower moving object. The extreme situation would be if an object could move as fast as the speed of light, its time would be completely halted. But whatever an object--or person's--time is, it's only evident in contrast to other objects. In other words, it's all relatives.

　　與太空旅行相比，時(shí)間旅行很顯然是一個(gè)更為復(fù)雜的命題。簡(jiǎn)而言之，愛(ài)因斯坦的觀點(diǎn)就是，宇宙中每一物體都有其自身的“時(shí)間”，并隨其運(yùn)動(dòng)的不同而不同。物體運(yùn)動(dòng)越快，其時(shí)間越慢(與運(yùn)動(dòng)較慢的物體相比而言)。最極端的假設(shè)是，如果一個(gè)物體運(yùn)動(dòng)達(dá)到光速，那么其時(shí)間就會(huì)完全停止。但無(wú)論一個(gè)物體或者一個(gè)人的時(shí)間為何，它只能參照其它物體才能得以體現(xiàn)。換句話說(shuō)，萬(wàn)物皆相對(duì)。