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One of the grandest scientific tools ever made by mankind is called an atom smasher.
在人类制造的众多伟大器械中，其中一样叫做'原子击碎器'。
And I mean literally grand.
我说的是体积上的大。
The biggest one ever built, the Large Hadron Collider, or LHC, is a ring with a circumference of about 18 miles.
其中最大的就是'大型强子对撞机'，或称'LHC'，是一个周长约18英里的环形建筑。
That's more than the entire length of Manhattan. So what is an atom smasher?
这比整个曼哈顿还长。原子击碎器到底是什么？
It is a device that collides atomic nuclei together at extremely high energy.
它是让具有极高能量的原子核互相撞击的仪器。
The most powerful one scientists have ever built can heat matter to the hottest temperatures ever achieved,
而科学家建造的能量最高的一个仪器，可以将物质加热到有史以来的最高温度，
temperatures last seen at a trillionth of second after the universe began.
相当于宇宙在诞生后的万亿分之一秒的温度。
Our accelerators are full of engineering superlatives.
我们的加速器由尖端工程技术构成。
The beam-containing region of the LHC is a vacuum, with lower pressure than what surrounds the international space station,
LHC的碰撞隧道是真空的，压力比国际太空站周围的气压还小，
and is 456 degrees Fahrenheit below zero, colder than the temperature of deepest space.
而且温度在零下456华氏度，比最深远的宇宙还要冷。
A previous accelerator sitting in the LHC tunnel holds the world record for velocity,
而先前的一个置于LHC加速碰撞隧道中的加速器，仍保持着速度的世界纪录，
accelerating an electron to a speed so fast that if it were to race a photon of light,
它能将一个电子加速到极高的速度，几乎接近于光速，
it would take about 14 minutes for the photon to get a lead of about 10 feet.
光子大约需要14分钟的时间才能领先10英尺。
If that doesn't impress you, remember the photon is fastest thing in the universe, it goes about 186,000 miles per second.
如果这还不让你惊讶，那么我要提醒你，光子是宇宙上最快的东西，它的时速大约为每秒18.6万英里。
So how do these subatomic particle accelerators work? Well, they use electric fields.
那么，这些次原子的粒子加速器是如何运作的？答案是利用电场。
Electric fields make charged particles move in the same way that gravity will pull a dropped baseball.
电场让带电粒子朝相同方向运动，就像重力把棒球向下拉一样。
The force from the electric field will pull a particle to make it move.
这样来自电场的力将吸引粒子且使它运动。
The speed will continue to increase until the charged particle is moving incredibly fast.
速度会继续增加，直到带电粒子达到惊人的速度。
A simple particle accelerator can be made by hooking two parallel metal plates to a battery.
将两块平行金属板和一颗电池相链接起来，就可制做一个简单的粒子加速器。
The charge from the battery moves on to the two metal plates and makes an electric field that pulls the particle along.
电池的电荷移动到两个金属板上，产生电场来吸引粒子移动。
And that's it, you got a particle accelerator.
就这么简单，这就是一个粒子加速器。
The problem is that an accelerator built this way is very weak.
问题是用这种方式打造的加速器的能量很小。
Building a modern accelerator like the LHC this way would take over five trillion standard D-cell batteries.
如果用这种方式打造大型强子对撞机，则需要超过五万亿个标准的一号电池。
So scientists use much stronger batteries and put them one after another.
因此，科学家们使用更高能的电池，并将它们串联起来。
An earlier accelerator used this method and was about a mile long and was equivalent to 30 billion batteries.
早期的加速器就采用了这种方法，这种加速器大约有一英里长，相当于300亿个电池。
However, to make an accelerator that is equivalent to five trillion batteries would require an accelerator 150 miles long.
但是要打造一个相当于5万亿个电池能量的加速器，则需要该加速器长达150英里。
Scientists needed another way.
因此，科学家们需要另一种方法。
While electric fields would make a particle go faster, magnetic fields make them move in a circular path.
电场可加速粒子，而磁场则可使它们沿圆环路径移动。
If you put an electric field along the circle, you don't need to use miles of electric fields,
如果把电场沿圆环路径安置，那么就不需要数英里长的电场，
you can use a single electric field over and over again.
你可以循环使用同一电场。
The beams go around the circle, and each time they gain more energy.
粒子会绕着圆圈运动，而每次循环，电子就可以获得更高的能量。
So very high-energy accelerators consist of a short region with accelerating electric fields,
所以高能加速器包含一小段的加速电场
combined with long series of magnets that guide the particles in a circle.
外加一个长串的、用于引导粒子沿圆环转圈的磁铁。
The strength of the magnets and the radius of the circular path determines the maximum energy of the beam.
磁场强度和圆环半径决定粒子束的最高能量。
Once the beam is zooming along, then the real fun begins, the smashing.
一旦粒子束达到极高速度，真正的乐趣就开始了--对撞。
The reason physicists want to get those particles moving so fast is so that they can slam them into one another.
物理学家之所以想要这些粒子高速运动，就是要让它们互相碰撞。
These collisions can teach us about the fundamental rules that govern matter,
这些碰撞可以帮助我们探寻物质必须遵守的基本原理，
but they'd be impossible without the feat of engineering, that is the particle accelerator.
但如果没有工程学上的成就这是不可能的。这就是粒子加速器。
