The Secret Force for Limitless Energy? Lasers | Tammy Ma | TED

翻译人员: Sue Lu 校对人员: Lening Xu

What would you do with the largest laser in the world?

你会用世界上最大的激光器做什么？

Send a beam into space.

向太空发射激光，

Strap the laser to the head of a shark.

将光束绑在鲨鱼头上，

Or maybe just use it to amuse your cat.

或是用它来逗你的猫。

Well, the laser that I'm talking about

好吧，我所说的激光

is nothing like your typical laser pointer.

与通常的激光笔完全不同。

No, this laser is a thousand times more powerful

这种激光功率千倍于

than the entire US electrical grid.

整个美国电网。

It's the most energetic laser in the world.

它是世界上能量最高的激光。

I guarantee you

我保证，

you're going to want to keep your cat far, far away from this laser.

你会让你的猫远离这束激光。

Now, I'm a physicist,

我是一名物理学家，

so what I would want to do with this laser is something a little bit different.

所以我想用这激光做点不同的事情。

I take that laser and split it into almost 200 beams,

我会把它分成近 200 道光束，

and shine them from every angle onto a little pellet of hydrogen.

从各个角度将这些光束 照射到一个小小的氢燃料颗粒上。

Hydrogen, that very first element on the periodic table.

氢，是元素周期表上第一个元素。

I'd use the laser to squeeze and compress that hydrogen

我会用激光挤压、压缩氢燃料，

until the atoms themselves fuse.

直到原子自身融合。

That's called fusion.

这就是所谓的核聚变。

And it’s the same reaction that powers the Sun.

为太阳提供能量的，正是这种聚变反应。

So with our giant laser,

因此，利用我们的巨型激光器，

we could actually create miniature stars right here on Earth.

可以在地球上创造出微型恒星。

Pretty cool, right?

很酷，对吧？

OK, that's the goal.

OK，这就是我们的目标。

But why?

但是为什么呢？

Why do we care to do this?

我们为什么要这样做？

Fusion means unlocking a different kind of nuclear power.

聚变意味着释放另一种核能。

Instead of splitting big, heavy atoms, like we do with fission

不同于裂变那样分裂大而重的原子——

in today's nuclear power plants,

裂变现在核电厂进行，

fusion means bringing together the atoms of a light element

聚变是将轻元素原子聚在一起

until they merge.

直到它们融合。

In our case, we're going to use deuterium and tritium.

我们做的，是使用氘和氚，

They are isotopes of hydrogen, heavy hydrogen.

它们是氢的同位素，即重氢。

And if we can use our lasers to get them close enough together

如果能用激光使它们靠得够近，

at hot enough temperatures,

并在够高的温度下，

and hold them there long enough until they fuse,

停留足够长的时间，直到融合，

what we create on the other side is a helium nucleus and a neutron.

那么我们在另一端创造出的 就是氦核和中子。

And it just so happens that that helium and neutron

碰巧的是，氦和中子,

weigh just a little bit less

其重量只比

than our deuterium and tritium originally did.

最初的氘和氚少一点。

So we're going to take that differential in mass

让我们将该重量差异

and put it into an equation that everybody knows really well.

用大家都明白的方程式表达出来。

Einstein's E equals --

爱因斯坦的 E 等于 ——

Audience: MC squared.

听众：mc 平方。

Tammy Ma: E equals MC squared.

Tammy Ma：E = mc2

Where that "m" is that differential in mass,

其中 “m”是质量差，

we're going to multiply by "c," the speed of light,

与 “c”相乘，即光速，

a huge, huge number squared,

一个巨大的数字平方，

and with that, get a tremendous amount of energy out.

代表的是大量释放的能量。

How tremendous?

有多大量？

Well one single pound of fusion fuel has the same amount of energy

1 磅聚变燃料的能量相当于

as 5,000 barrels of oil,

5,000 桶石油，

or 3.5 million pounds of coal.

或 350 万磅煤炭的能量。

So fusion is the ultimate energy source,

因此，聚变是终极能量来源，

not least because the fuel that we need for fusion is also very abundant.

尤其是，聚变所需燃料也很丰富。

Deuterium is naturally occurring in seawater.

氘（重水）天然存在于海水中，

About one in every 7,000 particles is D2O instead of H2O.

每 7,000 个水分子中就有 1 个 是重水（D₂O）而不是轻水（H₂O）。

And tritium, we know how to breed from lithium.

至于氚，我们知道如何从锂中培育。

So conceivably we actually have enough fusion fuel on Earth

理论上，地球上有足够的聚变燃料

to last us 30 billion years

供我们用 300 亿年，

of human consumption at today's levels.

这是按人类目前的消耗量计算的。

If you ask me, I'd call that energy security.

要我说，这就是能源保障。

Fusion is also clean energy.

聚变也是清洁能源。

In our equation,

在我们的方程式中，

it was a deuterium plus a tritium gave us a helium.

氘和氚结合产生了氦，

Carbon is nowhere in that equation.

碳在此没有容身之地。

Fusion is also inherently safe.

聚变本质上也是安全的。

In order to start a fusion reaction,

为了启动聚变反应，

we first have to put energy into the system to make the atoms fuse.

首先必须向系统输入能量，使原子融合。

So if you ever want to stop a fusion reaction,

因此，如果你想停止聚变反应，

you just cut off that initial energy source.

只需切断最初能量来源即可。

Fusion will create waste,

聚变会产生废料，

but it's not the kind of waste that will last for tens

但这种废料不会持续数万

or hundreds of thousands of years.

或数十万年。

Instead, the low-level nuclear waste of fusion

相反，聚变产生的低放核废料

can decay away in just decades.

可以在短短几十年内衰减殆尽。

And that means we can place fusion power plants almost anywhere,

因此，聚变发电厂可以安装在任何

near large population centers and big cities,

靠近人口密集中心和大城市的地方，

and fusion power plants would be compatible

而且发电厂与当前的电网基础设施

with our current grid infrastructure or the smart grids of the future.

或未来的智能电网都能兼容。

And finally, fusion energy is also flexible energy.

最后，聚变能源也是柔性能源，

Energy when you need it and can come in different forms.

可按照需要以不同形式出现：

Electricity to power our homes,

以电力形式为家庭供电，

but also high-temperature heat for industrial use.

以高温热量形式满足工业用途。

Now, to be fair, there are some downsides to fusion, too.

公正地说，聚变也有缺点，

Fusion is incredibly complex and incredibly difficult.

它非常复杂，非常难，

The development of fusion has been and will be expensive.

聚变的开发始终会很昂贵。

But the potential benefits of fusion are so great that it is worth it.

但聚变的潜在好处极大，值得一试。

All right, so how do we actually make fusion work here on Earth?

那么，如何让聚变真正发挥作用呢？

Well, that's the problem that we've been working on

这就是我们一直在研究的问题，

for nearly 60 years now.

已进行近 60 年了。

Let's go back to that ginormous laser.

让我们回到那台巨大的激光器。

It's called the National Ignition Facility, or NIF,

它被称为国家点火装置（NIF），

at the Lawrence Livermore National Lab.

位于劳伦斯·利弗莫尔国家实验室。

The NIF is the world's largest, most energetic laser,

NIF 是世界上最大、 能量最高的激光器，

housed in a building the size of three American football fields,

坐落在一栋大楼里， 大楼有三个并列美式足球场

side by side and ten stories tall.

那么大，并且有十层楼高。

It's not just one laser.

NIF 不只是一台激光器，

It's actually 192 separate lasers,

它由 192 台独立的激光器组成，

and each one alone is one of the most energetic in the world.

而每台都拥有世界上能量最高的激光。

And we're going to combine all 192 of those lasers

我们将把 192 束激光组合在一起，

and shine them on a little fuel pellet

照射到一个燃料颗粒上，

about the size of a peppercorn.

它只有胡椒粒大小。

Alright, let me take you into the facility and give you a closer look.

好吧，让我带你走近 NIF 看看。

The laser starts as a little pulse of light,

激光器从微小的光脉冲开始，

the fraction of the energy of a typical laser pointer.

只有普通激光笔能量的一小部分。

We're going to split that beam into 192 ways.

我们将把这束光分成 192 道光束，

And those beams are now going to bounce back and forth across this giant facility,

这些光束将在巨型装置中来回反射，

each beam passing through hundreds of slabs of laser glass

每束光会穿过数百块激光玻璃板，

getting boosted up in energy.

其能量由此得到增强。

In total, each beam is going to travel nearly a mile

总之，每束光将穿行近一英里，

and get amplified up a million billion times in energy

能量增大一千亿倍，

and expanded in size from a little pinprick

从针刺大小扩展到

to over a square foot.

超过一平方英尺。

And then all 192 laser beams are going to get directed

然后 192 束激光都将调头指向

towards the fusion chamber.

聚变室。

Half the laser beams go up and half come down,

一半光束向上，一半向下，

and they're going to direct and concentrate their light

将激光聚焦在

on a tiny cylinder that sits right in the middle,

位于正中央的小圆柱体上，

about the size of a pencil eraser.

圆柱体大小如橡皮擦。

The lasers go into that cylinder

激光进入圆柱体，

and create a bath of X-rays

生成 X 射线浴，

that then envelop the little fuel pellet

将圆柱体里的燃料颗粒包裹起来，

that sits right in the middle.

颗粒位于正中央。

Those X-rays are so intense

这些 X 射线极强，

that they start blowing off the shell of that pellet like a rocket.

像火箭般吹掉颗粒的外壳。

And then by conservation of momentum,

然后，通过动量守恒，

the rest of the capsule squeezes inward,

颗粒的其余部分向内挤压，

equal and opposite reaction.

产生等量和反作用力。

We're going to reach temperatures of over 180 million degrees Fahrenheit,

我们的温度将达到华氏 1.8 亿度以上，

hotter than the center of the Sun,

比太阳中心还热，

and pressures that would feel like 100 billion Earth atmospheres

压力就像 1000 亿个地球大气层

pressing down on you.

压在你身上。

And then we start a little spark right in the center,

然后，我们在中心点燃一个小火花，

which then propagates through more of that fuel,

火花通过燃料其它部分传播开来，

creating a miniature star,

形成一颗微型恒星，

and with it a huge burst of energy.

并随之产生巨大的能量输出。

And if we do it right,

如果我们做对了，

we can actually get a whole lot more energy out

可以得到多得多的能量，

than the energy that went in to start all of this.

远超过启动这一切时所输入能量。

(Applause)

（掌声）

I know, it sounds really easy, right?

我知道，听起来很简单，对吧？

(Laughter)

（笑声）

Well, obviously this is a story that bridges enormous scales.

显然，这是个跨度巨大的故事。

The temperature and density of a star focused in on the atomic level.

恒星的温度和密度集中在原子层面。

Remember how I said that laser is a thousand times the power

还记得我说过激光功率千倍于

of the US electrical grid?

美国电网功率吗？

Well, power is defined as energy per unit time.

功率被定义为每单位时间的能量。

So what we're doing is taking a huge amount of energy

因此，我们做的是把大量能量

and compressing it down into just nanoseconds.

压缩到短短的纳秒级。

And that's why every time we fire the lasers,

这就是为什么我们每次发射激光时，

the lights don't flicker across the globe.

全球的电灯不会因此而闪烁。

But we are able to create conditions that are the hottest

我们能够创造整个太阳系中

in the entire solar system.

最炽热的条件。

All right, so I know what you guys are all thinking.

好吧，我知道你们在想什么。

Like, how could this actually possibly work, right?

比如，这怎么可能行得通，对吧？

And who would be crazy enough to try?

有谁会疯狂到去尝试这一切？

Well, tens of thousands of scientists and engineers around the world,

全球成千上万的科学家和工程师，

including me.

包括我。

And scientists are trying all different approaches to fusion.

科学家们正在尝试各种聚变方法，

Not just giant lasers, but sometimes giant magnets.

不仅是巨型激光器，还有巨型磁铁，

Things that have cool names like tokamaks or stellarators

以及名字很酷的装置， 比如托卡马克（tokamak）或仿星器，

that can help shape and contain the fusion.

可以帮助塑造和遏制聚变。

And right now, we're actually seeing

现在，我们看到

a whole bunch of new, private start-up fusion companies

一大批新的私营初创核聚变公司，

pop up all across the globe,

在全球各地涌现。

each one trying a unique and different approach to fusion.

它们都在尝试独特的聚变方法。

It's a whole host of brave and brilliant individuals

一大批勇敢而才华横溢的人

working hard to make this dream a reality.

都在努力实现这个梦想。

And our team at Lawrence Livermore National Lab

我们在劳伦斯·利弗莫尔 国家实验室的团队

are the stewards of work that started in 1960

负责这项从 1960 年开始的工作，

because of national security.

We need to understand fusion,

我们需要了解聚变，

to understand how to ensure

了解如何确保

that our US nuclear arsenal stays safe and effective.

美国核武库的安全和效力。

And that is what has provided the steady funding

这就是为什么我们有稳定资金来源，

to pursue this very difficult physics challenge over decades.

数十年致力于攻克 这项艰巨的物理挑战。

So yeah, it took us 12 years to build the NIF,

是的，我们花了 12 年建造 NIF，

and we've been doing experiments using it

现在已使用它

for nearly 15 years more now.

进行了将近 15 年的实验。

And in that time, we've improved our physics understanding

那段时间，我们增进了对物理的理解，

and computational simulation models.

并改善了计算仿真模型。

We've designed new diagnostic instruments capable of taking better, clearer,

我们设计了新的诊断仪器， 能够更好、更清晰、

faster pictures of the experiment.

更快地拍摄实验照片。

We've continuously pushed up the laser energy

我们不断提高激光能量，

and found ways to build better targets.

并找到建造更好靶标的方法。

And guess what?

你猜怎么着？

In December of 2022, we finally did it.

2022 年 12 月，我们终于做到了。

(Applause)

（掌声）

Our team at Lawrence Livermore National Lab demonstrated fusion ignition.

我们在劳伦斯·利弗莫尔国家 实验室的团队实现聚变点火。

For the very first time in human history,

人类历史上首次，

we generated a controlled thermonuclear fusion reaction

在实验室完成受控热核聚变反应。

in the laboratory

that generated more energy out

这次反应产出的能量多于

than went in with the lasers to start it.

启动该反应时输入的激光能量。

(Applause)

（掌声）

That's right, we were able to light a match

没错，我们点燃了一根火柴，

and turn that into a bonfire.

然后把它变成熊熊篝火；

And in the process, release a new form of energy

在此过程中，释放一种新式能量，

that is a million times more energetic than a chemical reaction.

比化学反应的能量高出一百万倍。

And now,

现在，

now we've actually been able to repeat ignition four more times

实际上，我们已重复点火四次，

in just the last 15 months,

就在过去短短的 15 个月里。

with our most successful experiment

而我们最成功的实验，

giving us over twice as much energy out as we put in with the lasers.

产出能量是输入激光能量的两倍以上。

So are we done?

那么，我们达到目标了吗？

Well, not quite.

还差一点。

In order to move towards that fusion-energy future,

为了迈向聚变能源的未来，

we'll have to figure out how to harness this energy

我们必须弄清如何 在运行中的聚变发电厂

in a working fusion power plant.

利用这种能量。

And to be clear,

需要明确的是，

there's still a long scientific and engineering road ahead.

科学和工程技术的道路还很漫长。

Just to build on our successes at NIF,

为了在 NIF 成功的基础上再接再厉，

we'll have to build more efficient lasers,

我们必须制造更高效的激光器、

mass manufacture targets

制造大量靶标，

and figure out robotics for automated operations and more.

并开发自动化操作的机器人等。

The depth and breadth of this challenge

这一挑战的深度和广度，

will require sustained investment from government and private industry,

将需要政府和私营企业的持续投资，

and all of us working together.

以及我们所有人的共同努力。

We're all racing to make this a reality,

大家都在竞相努力使之成为现实，

but there's still a lot more work to be done.

但还有很多工作要做。

I don't know exactly how long this will all take,

我不确定到底还要多久，

but I do know that we can do it.

但我知道我们一定能成功。

And when we do it,

而且，到那时，

when we make fusion energy a reality,

当我们把聚变能源变为现实时，

energy will become so plentiful

能源将变得极其丰富，

that it will no longer be a limited resource.

不再是一种有限资源。

This will change the world as we know it.

这将彻底改变我们的世界。

When energy becomes essentially unlimited,

当能源变得取之不尽时，

there are unlimited ways to use this energy.

我们可以用无数的方式来利用它。

Every country will be energy independent.

每个国家都将实现能源独立，

Standards of living will rise around the world,

世界各地的生活水平都将提高。

and we'll be able to use energy in creative new ways as well,

我们将以创造性的新方式使用能源，

like carbon capture at scale to combat climate change.

例如，大规模碳捕集应对气候变化，

Vertical farming for delicious, sustainable food for all,

垂直农业为人类提供美味、可持续食物，

and desalination of seawater

还有海水淡化，

so that everybody has access to clean water.

让每个人都能获得清洁水源。

We can do all this and more with fusion.

聚变可以让我们实现这一切，

Fusion can ignite that future.

核聚变可以点燃未来。

Thank you.

谢谢大家。

(Applause)

（掌声）