TED演讲:时空穿越是可能的吗?(2)

 　　What would Jill, standing¹ on the platform, see through the window as the train whistles through? 这个时候站在月台上的吉尔会透过窗口所看到是什么？

　　Well, between Jack² dropping the ball and catching³ it again, 在杰克扔下球和接着球之间，

　　Jill would have seen him move slightly further down the track, resulting in her seeing the ball follow a triangular⁴ path. 吉尔会看到杰克和火车一起向前移动，结果她看到的球是以三角形的路线移动的。

　　This means Jill sees the ball travel further than Jack does in the same time period. 意思是，在同一个时间段里吉尔看到的球比杰克所看到的移动得更远。

　　And because speed is distance divided by time, Jill actually sees the ball move faster. 因为速度等于距离除以时间，事实上，吉尔所看到球比杰克所看到的移动得更快。

　　But what if Jack's bouncing ball is replaced with two mirrors which bounce a beam of light between them? 但是，如果我们把杰克的球用两面镜子作代替，而在镜子之间有一束光来回反弹。

　　Jack still sees the beam dropping down and Jill still sees the light beam travel a longer distance,  杰克依然会看到光束反弹，吉尔还是会看到该光束移动得更远，

　　except this time Jack and Jill cannot disagree on the speed because the speed of light remains⁵ the same no matter what. 例外的是，这次杰克和吉尔却会对光的速度有分歧。這是因为光的速度。无论如何还是保留不变。

　　And if the speed is the same while the distance is different, this means the time taken will be different as well. 如果速度是一样的话，而距离却不一样，那花的时间将也不一样。

　　Thus, time must tick at different rates for people moving relative to each other. 所以当人们对他人相对地移动时，时间一定以不一样的速率流逝。

　　Imagine that Jack and Jill have highly accurate watches that they synchronize⁶ before Jack boards the train. 试想如果杰克和吉尔都有非常精确的手表。他们在杰克上火车前校对好时间。

　　During the experiment, Jack and Jill would each see their own watch ticking normally. 当这个实验中，杰克和吉尔会看到自己的手表正常的走。

　　But if they meet up again later to compare watches,  但是如果他们在实验结束后相遇，比对彼此手表时，

　　less time would have elapsed on Jack's watch, balancing the fact that Jill saw the light move further. 他们会发现杰克的手表会走慢一些，因此解释了这事实：吉尔看到的光移动得更远。

　　This idea may sound crazy, but like any good scientific theory, it can be tested. 这听上去很诡异，但是，像任何一个完好的科学理论，它是可以被测试的。

　　In the 1970s, scientists boarded a plane with some super-accurate atomic clocks 在1970年左右，科学家们校对了一些超级准确的原子钟，一起带到飞机上去，

　　that were synchronized⁷ with some others left on the ground. 而数个原子钟则留在陆地上。

　　After the plane had flown around the world, the clocks on board showed a different time from those left behind. 当飞机环球飞行之后，他们发现飞机上的原子钟和地球上的原子钟上显示的时间是不一样的。

　　Of course, at the speed of trains and planes, the effect is minuscule⁸. 当然，以火车与飞机的速度，对时间膨胀的影响是很微小的。

1 standing   

n.持续，地位；adj.永久的，不动的，直立的，不流动的

参考例句：

• After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
• They're standing out against any change in the law.他们坚决反对对法律做任何修改。

2 jack   

n.插座，千斤顶，男人；v.抬起，提醒，扛举；n.（Jake）杰克

参考例句：

• I am looking for the headphone jack.我正在找寻头戴式耳机插孔。
• He lifted the car with a jack to change the flat tyre.他用千斤顶把车顶起来换下瘪轮胎。

3 catching   

adj.易传染的，有魅力的，迷人的，接住

参考例句：

• There are those who think eczema is catching.有人就是认为湿疹会传染。
• Enthusiasm is very catching.热情非常富有感染力。

4 triangular   

adj.三角（形）的，三者间的

参考例句：

• It's more or less triangular plot of land.这块地略成三角形。
• One particular triangular relationship became the model of Simone's first novel.一段特殊的三角关系成了西蒙娜第一本小说的原型。

5 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

6 synchronize   

v.使同步 [=synchronise]

参考例句：

• The sound on a film must synchronize with the action. 影片中的声音必须与动作配合一致。
• You must synchronize your Inbox before selecting additional folders. 在选择其他文件夹前，您必须同步您的收件箱。

7 synchronized   

同步的

参考例句：

• Do not use the synchronized keyword in Managed Objects. 不要在管理对象上使用synchronized关键字。 来自互联网
• The timing of the gun was precisely synchronized with the turning of the plane's propeller. 风门的调速与飞机螺旋桨的转动精确同步。 来自辞典例句

8 minuscule   

adj.非常小的；极不重要的

参考例句：

• The human race only a minuscule portion of the earth's history.人类只有占有极小部分地球历史。
• As things stand,Hong Kong's renminbi banking system is minuscule.就目前的情况而言，香港的人民币银行体系可谓微不足道。