万物简史 第175期:爱因斯坦的宇宙(18)(在线收听) |
However—and here’s the thing—people on the train would have no sense of these distortions. 然而——问题就在这里——车上的人并不觉得自己变了形。
To them, everything on the train would seem quite normal.
在他们看来,车上的一切似乎都很正常。
It would be we on the platform who looked weirdly compressed and slowed down.
倒是立在站台上的我们古怪地变小了,动作变慢了。
It is all to do, you see, with your position relative to the moving object.
你看,这一切都和你与移动物体的相对位置有关系。
This effect actually happens every time you move.
实际上,你每次移动都会产生这样的效果。
Fly across the United States, and you will step from the plane a quinzillionth of a second, or something, younger than those you left behind.
乘飞机越过美国,你会用大约一百亿亿分之一秒踏出飞机,比在你后面离开飞机的人要年轻一些。
Even in walking across the room you will very slightly alter your own experience of time and space.
即使从屋子的这头走到那头的时候,你自己所经历的时间和空间也会稍有改变。
It has been calculated that a baseball thrown at a hundred miles an hour will pick up 0.000,000,000,002 grams of mass on its way to home plate.
据计算,一个以每小时100公里的速度抛出去的棒球,在抵达本垒板的过程中会获得0.000,000,000,002克物质。
So the effects of relativity are real and have been measured.
因此,相对论的作用是具体的,可以测定的。
物理学历史上的两位巨人
The problem is that such changes are much too small to make the tiniest detectable difference to us.
问题在于,这种变化太小,我们毫无察觉。
But for other things in the universe—light, gravity, the universe itself—these are matters of consequence.
但是,对于宇宙中别的东西来说——光、引力、宇宙本身——这些就都是举足轻重的大事了。
So if the ideas of relativity seem weird, it is only because we don’t experience these sorts of interactions in normal life.
因此,如果说相对论的概念好像有点儿怪,那只是因为我们在正常的生活中没有经历这类相互作用。
However, to turn to Bodanis again, we all commonly encounter other kinds of relativity—for instance with regard to sound.
不过,又不得不求助于博尼丹斯,我们大家都经常遇到其他种类的相对论——比如声音。
If you are in a park and someone is playing annoying music, you know that if you move to a more distant spot the music will seem quieter.
要是你在公园里,有人在演奏难听的音乐,你知道,要是你走得远一点,音乐好像就会轻一点。
That’s not because the musicis quieter, of course, but simply that your position relative to it has changed.
当然,那并不是因为音乐真的轻了点,而只是因为你对于音乐的位置发生了变化。
To something too small or sluggish to duplicate this experience—a snail, say,
对于体积很小的或行动缓慢的,因此无法有同样经历的东西来说——比如蜗牛,
the idea that a boom box could seem to two observers to produce two different volumes of music simultaneously might seem incredible.
也许难以置信,一个喇叭似乎同时能对两个听众放出两种音量的音乐。 |
原文地址:http://www.tingroom.com/lesson/syysdw/wwwjs/386329.html |