Questions No One Knows the Answers to (Full Version)

无人知道答案的问题（完整版）

翻译人员: Binglin Qi 校对人员: Jing Peng

（音乐）

在学校,普通的一天里，

On a typical day at school,

无尽的时间要花在怎么去回答问题上，

endless hours are spent learning the answers to questions,

但是现在，我们不这么做了。

but right now, we'll do the opposite.

我们将把目光放在那些你不能够学到答案的问题上，

We're going to focus on questions where you can't learn the answers

因为它们是未知的。

because they're unknown.

I used to puzzle about a lot of things as a boy, for example:

我曾经在孩童时期对很多事情都有疑惑，

比如说，做一只狗会有什么样的生活呢？

What would it feel like to be a dog?

鱼会感觉到疼痛么？

Do fish feel pain?

How about insects?

昆虫会不会呢？

Was the Big Bang just an accident?

难道宇宙大爆炸仅仅是个意外么？

上帝真的是存在的么？

And is there a God?

And if so, how are we so sure that it's a He and not a She?

如果存在的话，我们怎么能够确定上帝是男的还是女的呢？

为什么世界上这么多的无辜的人和动物要遭受一些可怕的事情？

Why do so many innocent people and animals suffer terrible things?

我的生活真的是被计划好的么？

Is there really a plan for my life?

未来是还没被决定的呢，

Is the future yet to be written,

or is it already written and we just can't see it?

还是说未来是已经被写好了的，只不过我们看不见？

But then, do I have free will? I mean, who am I anyway?

然后，我有自由的意志么？我到底是谁呢？

Am I just a biological machine?

我仅仅是一台生物机器么？

But then, why am I conscious? What is consciousness?

然后，我为什么会有意识呢？意识又是什么东西？

机器人以后也会有意识么？

Will robots become conscious one day?

我是说，我稍微假设一下，在某一天

I mean, I kind of assumed that some day

我会有这些问题的答案，

I would be told the answers to all these questions.

那么肯定是有人知道答案的对吧？

Someone must know, right?

你猜猜？没有人知道。

Guess what? No one knows.

大部分这些问题带给我的困扰与日俱增。

Most of those questions puzzle me more now than ever.

但是探索这些问题答案的过程真的很有趣

But diving into them is exciting

因为它带你到了知识的边缘，你永远不知道你将在那里发现什么。

because it takes you to the edge of knowledge,

and you never know what you'll find there.

所以，这里有两个问题——

So, two questions that no one on Earth knows the answer to.

这两个问题地球上没有人可以回答出来。

（音乐）世界上有多少的宇宙呢？

(Music)

[How many universes are there?]

Sometimes when I'm on a long plane flight,

有时候, 当我坐在远途飞行的飞机上,

I gaze out at all those mountains and deserts

我会向外俯瞰那些山川和沙漠

and try to get my head around how vast our Earth is.

然后尝试着猜测我们的地球到底有多广袤无垠。

接着我记得我们每天都能看见一个物体的出现，

And then I remember that there's an object we see every day

它还可以装进一百万个地球：

that would literally fit one million Earths inside it:

太阳。它看起来真的是不可思议般的大！

the Sun.

It seems impossibly big.

But in the great scheme of things, it's a pinprick,

但是在浩瀚的宇宙中，它不过一个针孔大小而已，

是银河系中四千亿星星的一员，

one of about 400 billion stars in the Milky Way galaxy,

正如你可以在晴朗的晚上

which you can see on a clear night

看到满天的星星好似淡淡的白雾

as a pale white mist stretched across the sky.

然而更令人惊叹的是, 通过天文望远镜我们可以

And it gets worse.

There are maybe 100 billion galaxies detectable by our telescopes.

探测到大约一千亿个的星系。

So if each star was the size of a single grain of sand,

所以如果每个星星都是沙子中的一粒的话，

仅仅银河系就有足够的星星让

just the Milky Way has enough stars

to fill a 30-foot by 30-foot stretch of beach

一个30英尺长30英尺宽的沙滩

three feet deep with sand.

盖上3英尺厚。

And the entire Earth doesn't have enough beaches

整个地球上的沙滩甚至还不能

to represent the stars in the overall universe.

代表宇宙中所有的星星。

这样的一个沙滩会大约绵延几亿英里长。

Such a beach would continue for literally hundreds of millions of miles.

天啊，史蒂芬 霍金，这可是超级多的星星啊！

Holy Stephen Hawking, that is a lot of stars.

But he and other physicists now believe in a reality

但是他还有其他物理学家现在相信事实上

that is unimaginably bigger still.

还会比现在的大不知道多少，完全没法想象。

我的意思是，首先，这些我们可以观测到的一千亿星系

I mean, first of all, the 100 billion galaxies

within range of our telescopes

are probably a minuscule fraction of the total.

可能不过是总数的很小一部分。

Space itself is expanding at an accelerating pace.

空间现在仍在在加速拓展。

绝大部分的星系

The vast majority of the galaxies

are separating from us so fast that light from them may never reach us.

正在以一个比光还要快的速度离我们而去，他们的光都不可能到达地球。

但是，事实上我们地球上的物理现象

Still, our physical reality here on Earth

是和那些遥远的看不见的星系有着很密切的关系。

is intimately connected to those distant, invisible galaxies.

We can think of them as part of our universe.

我们可以把它们看作宇宙中的一部分。

They make up a single, giant edifice

它们组成了一个巨大的宏伟建筑物

obeying the same physical laws and all made from the same types of atoms,

所有的建筑物里的物质都遵循相同的物理定律，由相同的微粒组成, 原子, 电子，质子，

electrons, protons, quarks, neutrinos, that make up you and me.

夸克，中微子——那些形成了我们的微粒。

然而，物理学最近的理论显示，包括弦理论，

However, recent theories in physics, including one called string theory,

are now telling us there could be countless other universes

告诉我们世界上可能会有数不完的其他宇宙

built on different types of particles,

由不同于我们的宇宙的微粒组成，

with different properties, obeying different laws.

有不同的性质，遵循不同的规律。

Most of these universes could never support life,

大部分的宇宙可能永远不能产生生命，

and might flash in and out of existence in a nanosecond.

或者生命在一纳秒内存在然后消失了。

但是，无论如何,它们组成了巨大的多元宇宙,

But nonetheless, combined, they make up a vast multiverse

可能一共有11维，

of possible universes in up to 11 dimensions,

featuring wonders beyond our wildest imagination.

在我们的想象力之外创造着奇迹。

领先的弦理论预测一个多元宇宙

The leading version of string theory predicts a multiverse

可以组成10的500次方个不同的宇宙。

made up of 10 to the 500 universes.

That's a one followed by 500 zeros,

就是1后面跟著500个0，

a number so vast that if every atom

这个数字是如此之大以至于我们观测宇宙中的

in our observable universe had its own universe,

每个原子都有自己的宇宙，

所有的宇宙中的所有原子都有

and all of the atoms in all those universes each had

their own universe,

自己的宇宙。你再重复

and you repeated that for two more cycles,

两次同样的循环，你得到的仍然是

you'd still be at a tiny fraction of the total,

总数的一小部分，

namely, one trillion trillion trillion trillion trillion trillion trillion

也就是大约10的180次方分之一。

trillion trillion trillion trillion trillion trillion trillion trillionth.

(Laughter)

即便是这个数字，

But even that number is minuscule compared to another number:

相比另一个数字也是小数目：

无限。

infinity.

Some physicists think the space-time continuum is literally infinite

部分物理学家认为时空连续到几乎是无限的

and that it contains an infinite number of so-called pocket universes

它包括了无限的所谓的子宇宙

和所有的可能。

with varying properties.

你的大脑现在怎么样了？

How's your brain doing?

量子理论给了我们一个全新的视野。

Quantum theory adds a whole new wrinkle.

I mean, the theory's been proven true beyond all doubt,

我的意思是，这个理论证明了所有的疑惑，

but interpreting it is baffling,

但是证明和解释起来却非常的困难，

and some physicists think you can only un-baffle it

有些物理学家认为要解释疑惑就

必须要你想象世界上有无数的平行宇宙

if you imagine that huge numbers of parallel universes

are being spawned every moment,

在每个瞬间都在像产卵一样分化，

这些宇宙中有许多会跟我们所在的世界很相似，

and many of these universes would actually be very like the world we're in,

would include multiple copies of you.

并且会有多个你这个人的副本。

In one such universe, you'd graduate with honors

在这些宇宙中，你会以荣誉学位毕业

and marry the person of your dreams, and in another, not so much.

并且嫁给一位梦中情人，

而在另一个宇宙中的你,活的不那么好。

Well, there are still some scientists who would say, hogwash.

好吧，仍然会有一些科学家会说，这是废话。

The only meaningful answer to the question of how many universes there are is one.

这里唯一有意义的回答:世界上有多少宇宙的答案是一个。

仅仅一个宇宙。

Only one universe.

And a few philosophers and mystics might argue

有少部分哲学家和神学家

that even our own universe is an illusion.

会说即便我们的宇宙也是幻觉, 不真实存在的。

所以，你可以看到，现在

So, as you can see, right now

there is no agreement on this question, not even close.

世界上没有对于这个问题的统一回答，甚至还没有可以回答的迹象

All we know is the answer is somewhere between zero and infinity.

我们只知道这个答案介于0到无穷大之间。

让我们来说一下另一件事。

Well, I guess we know one other thing.

This is a pretty cool time to be studying physics.

这是一个非常有趣的学习物理的机会。

We just might be undergoing the biggest paradigm shift in knowledge

我们可能正在经历人类史上

that humanity has ever seen.

最大的知识范例变动。

(Music)

（音乐）为什么我们看不到外星人的迹象？

[Why can't we see evidence of alien life?]

Somewhere out there in that vast universe

在浩瀚宇宙的某一处，

there must surely be countless other planets teeming with life.

肯定会有个地方会有无数的星球在大量的孕育出生命。

But why don't we see any evidence of it?

但是为什么我们就看不到那些迹象呢？

这个著名问题在1950年由Enrico Fermi提出：

Well, this is the famous question asked by Enrico Fermi in 1950:

其他生命到底在哪里？

Where is everybody?

阴谋论的理论家认为不明飞行物经常飞到地球来

Conspiracy theorists claim that UFOs are visiting all the time

and the reports are just being covered up,

并且有关的报告被隐藏了，但是说实话，这个并不能令人信服。

but honestly, they aren't very convincing.

But that leaves a real riddle.

但这就留下了一个谜。

在过去的时间里，开普勒空间瞭望台

In the past year, the Kepler space observatory

发现了几百颗行星在恒星附近环绕。

has found hundreds of planets just around nearby stars.

如果外推一下这个数据，

And if you extrapolate that data,

it looks like there could be half a trillion planets

这好像是有5000亿个行星

just in our own galaxy.

在银河系中。

如果有万分之一的行星有条件

If any one in 10,000 has conditions

that might support a form of life,

孕育生命，这依然有

that's still 50 million possible life-harboring planets

五千万适合生命的行星。

right here in the Milky Way.

这仅仅是在银河系。

So here's the riddle:

所以这个谜就是：我们地球的存在

our Earth didn't form

until about nine billion years after the Big Bang.

是在大爆炸的九十亿年之后。

无数的银河系内其他行星会在地球之前形成

Countless other planets in our galaxy should have formed earlier,

并且让生命可以进化。

and given life a chance to get underway

billions, or certainly many millions of years earlier than happened on Earth.

它们要比地球早几十亿年，或者最起码早几百万年

就已经出现了。

If just a few of them had spawned intelligent life

如果只有一少部分生命进化出了有智慧的

and started creating technologies,

和可以创造科技的生命，

those technologies would have had millions of years

那些科技将会有几百万年的时间

to grow in complexity and power.

去发展出对应的复杂度和能力。

在地球上，

On Earth,

we've seen how dramatically technology can accelerate

我们见证了科技在仅仅100年内

in just 100 years.

是怎样急剧发展的。

In millions of years, an intelligent alien civilization

在数百万年内，一个有智慧的外星文明

肯定可以轻易地发展到银河系的每一个角落，

could easily have spread out across the galaxy,

perhaps creating giant energy-harvesting artifacts

或许发明了巨型能源捕获机这样的东西。

或者是殖民飞行舰队

or fleets of colonizing spaceships

或者是充满了夜晚天空的辉煌艺术作品。

or glorious works of art that fill the night sky.

至少你想它们也会

At the very least, you'd think they'd be revealing their presence,

把它们的存在，有意或无意的,

deliberately or otherwise,

through electromagnetic signals of one kind or another.

通过一种或其他的电磁信号告诉我们。

但是现在没有充分证据显示有任何一种文明。

And yet we see no convincing evidence of any of it.

Why?

为什么呢？

Well, there are numerous possible answers, some of them quite dark.

这里会有很多可能的答案，

其中有些相当消极。

Maybe a single, superintelligent civilization

可能一个非常有智能的文明

has indeed taken over the galaxy

已经占领了整个银河系并且故意把辐射波屏蔽了，

and has imposed strict radio silence

because it's paranoid of any potential competitors.

因为它们害怕潜在的竞争对手。

It's just sitting there ready to obliterate

他们可能就坐等去消灭

anything that becomes a threat.

任何可能成为隐患的东西。

或者它们还不够聪明，

Or maybe they're not that intelligent,

或者可能在进化出一个

or perhaps the evolution of an intelligence

capable of creating sophisticated technology

能够创造复杂科技的智能生物

is far rarer than we've assumed.

是远比我们想象的要难。总而言之，

After all, it's only happened once on Earth in four billion years.

在40亿年智能生物至此只在地球发生过一次。

Maybe even that was incredibly lucky.

或许这是巧合的巧合。

Maybe we are the first such civilization in our galaxy.

或许我们是银河系内第一个有如此程度文明的。

或者，可能

Or, perhaps civilization carries with it the seeds of its own destruction

文明携带毁灭自己文化的种子

这些种子通过以不能控制自己科技进步的方式衍生着。

through the inability to control the technologies it creates.

但这里有更多充满希望的答案。

But there are numerous more hopeful answers.

For a start, we're not looking that hard,

作为开始，我们没有努力去搜索它们，我们只是花了很少一部分钱而已。

and we're spending a pitiful amount of money on it.

仅仅是银河系中的很小一部分行星

Only a tiny fraction of the stars in our galaxy

have really been looked at closely for signs of interesting signals.

被我们仔细研究了它们的使我们感兴趣的信号。

或许我们没有找对方向。

And perhaps we're not looking the right way.

可能一个文明发展得

Maybe as civilizations develop,

they quickly discover communication technologies

太快以致于它们使用一些

far more sophisticated and useful than electromagnetic waves.

比电磁波更加复杂有用的信号。

可能所有的活动都是在谜一般的

Maybe all the action takes place inside the mysterious

recently discovered dark matter,

最近发现的暗物质里发生的。

or dark energy, that appear to account for most of the universe's mass.

或者是揭示了宇宙大部分质量的暗能量，

或者

Or, maybe we're looking at the wrong scale.

可能我们找错了大小范围。

Perhaps intelligent civilizations come to realize

可能智能文明意识到了

that life is ultimately just complex patterns of information

生命最终不过是复杂的信息模式

interacting with each other in a beautiful way,

互相以一种美丽的方式作用于其他个体，

and that that can happen more efficiently at a small scale.

它们可能在更小的情况下表现的更加有效率。

So, just as on Earth, clunky stereo systems have shrunk

所以，就像笨重的音响系统变小了，

to beautiful, tiny iPods, maybe intelligent life itself,

变成精致小巧的ipods；或者是智能生物本身变小，

in order to reduce its footprint on the environment,

这样可以减少在环境中留下的足迹，让他们变成微观物体。

has turned itself microscopic.

So the Solar System might be teeming with aliens,

所以，在太阳系可能充满了外星人，只不过我们没发现而已。

and we're just not noticing them.

Maybe the very ideas in our heads are a form of alien life.

可能我们脑中的那个想法就是一种外星生命的形式。

好吧，真是一个疯狂的想法。

Well, okay, that's a crazy thought.

外星人让我说的。

The aliens made me say it.

But it is cool that ideas do seem to have a life all of their own

但这个好想法的确有自己的一套生命的解释

而且它们比它们的创造者活得更久。

and that they outlive their creators.

可能生命体只是一个转瞬即逝的阶段。

Maybe biological life is just a passing phase.

好吧，在未来的15年内，

Well, within the next 15 years,

we could start seeing real spectroscopic information

我们可以开始看到真正的光谱学信息

from promising nearby planets

从附近有希望的行星开始去揭示一个星球有多适合居住。

that will reveal just how life-friendly they might be.

另一方面，有个叫做"搜寻外星智能生物"的组织，也叫SETI，

And meanwhile, SETI, the Search for Extraterrestrial Intelligence,

is now releasing its data to the public

现在把自己的数据公之于众，

so that millions of citizen scientists, maybe including you,

这样成百万计的科学家，可能也包括你，

can bring the power of the crowd to join the search.

可以发动群众的力量去加入这个搜索。

并且在地球，人们在做一种神奇的实验

And here on Earth, amazing experiments

are being done to try to create life from scratch,

去寻找随机创造出生命，

life that might be very different from the DNA forms we know.

而且它们的DNA会跟我们有很大不同。

所有的这些会让我们了解

All of this will help us understand whether the universe is teeming with life

这个宇宙是不是充满了生命

or whether, indeed, it's just us.

或者，真的，只有我们。

任何一个答案，就它们本身而言，

Either answer, in its own way,

都是令人惊讶的，

is awe-inspiring,

因为即便只有我们存在,

because even if we are alone,

the fact that we think and dream and ask these questions

这些思考与梦想,这些疑问本身,

可能会变成宇宙中最重要的事实之一。

might yet turn out to be

one of the most important facts about the universe.

我还有一个好消息给你。

And I have one more piece of good news for you.

对知识的渴望不会让你生活乏味,

The quest for knowledge and understanding never gets dull.

It doesn't. It's actually the opposite.

不但不会，还会反过来。

The more you know, the more amazing the world seems.

你知道的越多，对你来说这个世界就越神奇。

And it's the crazy possibilities, the unanswered questions,

还有这些疯狂的可能性还有没回答的问题，

它们使我们向前。

that pull us forward.

So stay curious.