I'm in the business of safeguarding secrets, and this includes your secrets.
我从事保护秘密的工作，其中就包括你们的秘密。
Cryptographers are the first line of defense in an ongoing war that's been raging for centuries:
密码学家是数百年来持续不断的战争中的第一道防线：
a war between code makers and code breakers.
是代码编写者和代码破译者之间的战争。
And this is a war on information. The modern battlefield for information is digital.
这是一场信息战争。现代信息战场是数字化的。
And it wages across your phones, your computers and the internet.
它发动于你的手机、你的电脑和互联网。
Our job is to create systems that scramble your emails and credit card numbers,
我们的工作是建立系统，来打乱你们的电子邮件内容，信用卡号，
your phone calls and text messages and that includes those saucy selfies
电话内容和短信，这包括那些搞笑的自拍照，
so that all of this information can only be descrambled by the recipient that it's intended for.
这样，所有的这些信息只能由预期的接收者解密。
Now, until very recently, we thought we'd won this war for good.
一直以来，我们都一直以为自己永远赢得了这场战争。
Right now, each of your smartphones is using encryption that we thought was unbreakable and that was going to remain that way.
现在，你们每个人的手机都在使用我们认为永远无法被破解的加密手段。
We were wrong, because quantum computers are coming, and they're going to change the game completely.
我们错了，因为量子计算机即将加入这场战争，它们会彻底改变游戏规则。
Throughout history, cryptography and code-breaking has always been this game of cat and mouse.
纵观历史，密码学和密码破解一直是猫和老鼠的游戏。
Back in the 1500s, Queen Mary of the Scots thought she was sending encrypted letters that only her soldiers could decipher.
回到十五世纪，苏格兰的玛丽女王认为她正在发送只有她的士兵可以破解的加密信件。
But Queen Elizabeth of England, she had code breakers that were all over it.
但是英格兰的伊丽莎白女王手下有无数的密码破译者。
They decrypted Mary's letters, saw that she was attempting to assassinate Elizabeth and, subsequently, they chopped Mary's head off.
他们破解了玛丽的信件，发现了她正试图刺杀伊丽莎白，随后，他们砍掉了玛丽的头。
A few centuries later, in World War II, the Nazis communicated using the Engima code,
几个世纪之后的第二次世界大战，纳粹使用恩尼格玛密码进行通讯，
a much more complicated encryption scheme that they thought was unbreakable.
是一种他们认为牢不可破的更复杂的加密机制。
But then good old Alan Turing, the same guy who invented what we now call the modern computer,
但是之后的艾伦·图灵，那个发明了我们称为现代计算机的人，
he built a machine and used it to break Enigma.
制作了一个机器，用它来破解恩尼格玛。
He deciphered the German messages and helped to bring Hitler and his Third Reich to a halt.
他破译了德国人的消息，并协助使得希特勒和他的第三帝国停滞不前。
And so the story has gone throughout the centuries.
这种故事已经重复了多个世纪。
Cryptographers improve their encryption, and then code breakers fight back and they find a way to break it.
密码学家不断改善他们的加密方式，然后密码破译者进行反击，找到一种方法来破解它。
This war's gone back and forth, and it's been pretty neck and neck.
这场战争来来回回，而且双方差不多并驾齐驱。
That was until the 1970s, when some cryptographers made a huge breakthrough.
直到19世纪70年代，一些密码学家取得了巨大的突破。
They discovered an extremely powerful way to do encryption called "public-key cryptography."
他们发现了一种非常强大的加密方式，叫做“公钥密码学”。
Unlike all of the prior methods used throughout history,
与之前用过的所有方式不同，
it doesn't require that the two parties that want to send each other confidential information have exchanged the secret key beforehand.
它不需要想要交换秘密信息的通讯双方提前交换密钥。
The magic of public-key cryptography is that it allows us to connect securely with anyone in the world,
公钥密码学的魔力在于，它允许我们安全地与世界上任何人连接起来，
whether we've exchanged data before or not, and to do it so fast that you and I don't even realize it's happening.
无论我们事先交换过数据与否，它能让我们可以快速地通讯，甚至没有意识到它正在发生。
Whether you're texting your mate to catch up for a beer, or you're a bank that's transferring billions of dollars to another bank,
无论你正给同伴发短信相约喝酒，还是你正在转账数十亿美元到另一家银行，
modern encryption enables us to send data that can be secured in a matter of milliseconds.
现代加密技术使我们能够在几毫秒内发送被保护的数据。
The brilliant idea that makes this magic possible, it relies on hard mathematical problems.
使这个魔法成为可能的绝妙主意，依赖于困难的数学问题。
Cryptographers are deeply interested in things that calculators can't do.
密码学家对计算器无法做到的事情深感兴趣。
For example, calculators can multiply any two numbers you like, no matter how big the size.
例如，计算器可以让你喜欢的任何两个数字相乘，无论数字有多大。
But going back the other way -- starting with the product and then asking, "Which two numbers multiply to give this one?"
但是反过来--有相乘后的结果，然后问“哪两个数字相乘得出的这个数字？”
that's actually a really hard problem.
这实际上是个非常难的问题。
If I asked you to find which two-digit numbers multiply to give 851, even with a calculator,
如果我让你找出哪两个两位数相乘等于851，即使有计算器，
most people in this room would have a hard time finding the answer by the time I'm finished with this talk.
这个房间里的大多数人在我完成本次演讲之前，都很难找到答案。
And if I make the numbers a little larger, then there's no calculator on earth that can do this.
而且如果我让数字变得更大些，地球上没有任何计算器可以做到。
In fact, even the world's fastest supercomputer
实际上，甚至是世界上最快的超级电脑
would take longer than the life age of the universe to find the two numbers that multiply to give this one.
要找到两个相乘得到该数字的数字，将花费比宇宙寿命更长的时间。
And this problem, called "integer factorization,"
而这个问题，被叫做“整数分解”，
is exactly what each of your smartphones and laptops is using right now to keep your data secure.
就是现在你们每部手机和电脑正在用来保护你们的数据安全的方法。
This is the basis of modern encryption.
这是现代加密的基础。
And the fact that all the computing power on the planet combined can't solve it,
而地球上所有计算能力联合起来也无法解决这个问题的事实，
that's the reason we cryptographers thought we'd found a way to stay ahead of the code breakers for good.
正是我们密码学家认为我们找到了一种方式能永远领先于编码破坏者的原因。
Perhaps we got a little cocky because just when we thought the war was won,
也许我们有点自大，因为就在我们以为战争胜利的时候，
a bunch of 20th-century physicists came to the party, and they revealed that the laws of the universe,
一批20世纪的物理学家也加入了进来，他们揭示了宇宙的定律，
the same laws that modern cryptography was built upon, they aren't as we thought they were.
并不是我们想象的那样，而现代密码学的建立就基于这些定律。
We thought that one object couldn't be in two places at the same time. It's not the case.
我们认为一个物体不能同时处于两个地方。事实并非如此。
We thought nothing can possibly spin clockwise and anticlockwise simultaneously. But that's incorrect.
我们认为没有任何东西可以同时进行顺时针和逆时针旋转。但这也不是正确的。
And we thought that two objects on opposite sides of the universe, light years away from each other,
我们认为分别位于宇宙两侧的两个物体彼此相距若干光年，
they can't possibly influence one another instantaneously. We were wrong again.
它们不可能瞬间相互影响。我们又错了。
And isn't that always the way life seems to go?
生活也总是这样，不是吗？
Just when you think you've got everything covered, your ducks in a row, a bunch of physicists come along
就在你认为你搞定了所有事情，万事俱备的时候，一批物理学家出现，
and reveal that the fundamental laws of the universe are completely different to what you thought?
并揭示了宇宙的基本定律与你想的完全不同？
And it screws everything up.
它搞砸了一切。
See, in the teeny tiny subatomic realm, at the level of electrons and protons,
结果就是，在微小的亚原子领域，在电子和质子的级别上，
the classical laws of physics, the ones that we all know and love, they go out the window.
我们都熟知和热爱的物理的经典定律，不复存在。
And it's here that the laws of quantum mechanics kick in.
而量子力学定律就在这里展开。
In quantum mechanics, an electron can be spinning clockwise and anticlockwise at the same time,
在量子力学中，电子可以同时进行顺时针和逆时针旋转，
and a proton can be in two places at once.
而一个质子可以同时处于两个位置。
It sounds like science fiction, but that's only because the crazy quantum nature of our universe, it hides itself from us.
这听起来像科幻小说，但是这仅仅是因为宇宙的疯狂量子本质，对我们隐藏了自己。
And it stayed hidden from us until the 20th century.
直到20世纪它才被我们发现。
But now that we've seen it, the whole world is in an arms race to try to build a quantum computer
但是现在我们看见了，整个世界都在争相尝试建造量子计算机，
a computer that can harness the power of this weird and wacky quantum behavior.
一种能够利用古怪的量子行为力量的计算机。
These things are so revolutionary and so powerful that they'll make today's fastest supercomputer look useless in comparison.
这些东西太具有颠覆性了，而且如此强大，会使得现在最快的超级计算机相比之下看起来毫无用处。
In fact, for certain problems that are of great interest to us,
实际上，对于我们非常感兴趣的某些问题，
today's fastest supercomputer is closer to an abacus than to a quantum computer.
如今最快的超级电脑更接近于一个算盘，而不是量子计算机。
That's right, I'm talking about those little wooden things with the beads.
是的，我说的就是那种带有珠子的小小的木制品。
Quantum computers can simulate chemical and biological processes that are far beyond the reach of our classical computers.
量子计算机可以模拟化学和生物过程，这远远超出了传统计算机的范围。
And as such, they promise to help us solve some of our planet's biggest problems.
因此，它们很可能会帮助我们解决地球上一些最大的问题。
They're going to help us combat global hunger; to tackle climate change;
他们将帮助我们战胜全球饥饿；应对气候变化；
to find cures for diseases and pandemics for which we've so far been unsuccessful; to create superhuman artificial intelligence;
找到我们迄今为止未能成功的治疗疾病和全球性传染病的方法；创造超人类的人工智能；
and perhaps even more important than all of those things, they're going to help us understand the very nature of our universe.
以及比所有这些事情都重要的，它将帮助我们理解宇宙的本质。
But with this incredible potential comes an incredible risk.
但是伴随着不可思议的潜力，也带来了不可思议的风险。
Remember those big numbers I talked about earlier? I'm not talking about 851.
还记得我之前说过的大数字吗？我现在说的不是851。
In fact, if anyone in here has been distracted trying to find those factors,
实际上，如果你们任何人因为要找到这些因数而分心，
I'm going to put you out of your misery and tell you that it's 23 times 37.
我要把你从苦难中解救出来，告诉你答案是23乘37。
I'm talking about the much bigger number that followed it.
我要说的是比那大得多的数字。
While today's fastest supercomputer couldn't find those factors in the life age of the universe,
虽然当今最快的超级计算机无法在宇宙生命周期中找到那些因数，
a quantum computer could easily factorize numbers way, way bigger than that one.
但一个量子计算机可以轻易的分解比那大很多很多的数字。
Quantum computers will break all of the encryption currently used to protect you and I from hackers. And they'll do it easily.
量子计算机将打破我们现在用来保护大家免受黑客攻击的所有加密算法。它们会轻松做到的。

Let me put it this way: if quantum computing was a spear, then modern encryption,
让我这样说吧：如果量子计算是一根长矛，那么现代加密，
the same unbreakable system that's protected us for decades, it would be like a shield made of tissue paper.
几十年来一直保护着我们的牢不可破的系统，就像是纸巾做的盾牌。
Anyone with access to a quantum computer will have the master key to unlock anything they like in our digital world.
有权访问量子计算机的任何人都将拥有万能钥匙，可以解锁他们在数字化世界中喜欢的任何东西。
They could steal money from banks and control economies. They could power off hospitals or launch nukes.
他们可以从银行偷钱，并控制经济。他们可以关闭医院电源，或者发射核武器。
Or they could just sit back and watch all of us on our webcams without any of us knowing that this is happening.
或者他们可以只是坐下来，通过网络摄像头看着我们，而我们没有人知道发生了什么。
Now, the fundamental unit of information on all of the computers we're used to, like this one, it's called a "bit."
我们习惯使用的所有计算机上的基本信息单元，像这个，叫做一个“比特”。
A single bit can be one of two states: it can be a zero or it can be a one.
一个比特可以处于两个状态之一：它可以是0或者1。
When I FaceTime my mum from the other side of the world -- and she's going to kill me for having this slide
当我和地球另一端的妈妈视频的时候--她会因为我做了这张幻灯片杀了我的，
we're actually just sending each other long sequences of zeroes and ones
我们实际上只是在给彼此发送一长串的0和1，
that bounce from computer to computer, from satellite to satellite, transmitting our data at a rapid pace.
在计算机之间、卫星之间反复，高速地传输着我们的数据。
Bits are certainly very useful. In fact, anything we currently do with technology is indebted to the usefulness of bits.
比特当然非常有用。实际上，我们现在技术上做的任何事情都多亏了比特。
But we're starting to realize that bits are really poor at simulating complex molecules and particles.
但是我们开始意识到，在模拟复杂的分子和粒子方面，比特做得很差。
And this is because, in some sense, subatomic processes can be doing two or more opposing things at the same time
这是因为，在某种意义上，亚原子过程可以同时做两个或更多相反的事情，
as they follow these bizarre rules of quantum mechanics.
因为他们遵循量子力学的这些怪异规则。
So, late last century, some really brainy physicists had this ingenious idea:
所以，上个世纪后期，一些非常聪明的物理学家有了这个巧妙的想法：
to instead build computers that are founded on the principles of quantum mechanics.
建立基于量子力学原理的计算机。
Now, the fundamental unit of information of a quantum computer, it's called a "qubit." It stands for "quantum bit."
量子计算机的基本信息单位叫做一个“量子比特”（qubit），是“quantum bit”的缩写。
Instead of having just two states, like zero or one, a qubit can be an infinite number of states.
一个量子比特可以有无限个状态，而不再是只有0或1两个状态。
And this corresponds to it being some combination of both zero and one at the same time, a phenomenon that we call "superposition."
这对应于它同时是0和1的某种组合，我们称这种现象为“叠加”。
And when we have two qubits in superposition,
当我们有两个量子比特叠加在一起时，
we're actually working across all four combinations of zero-zero, zero-one, one-zero and one-one.
实际上，我们正在研究四种组合，0-0，0-1，1-0，和1-1。
With three qubits, we're working in superposition across eight combinations, and so on.
有三个量子比特时，我们在研究八种组合的叠加状态，以此类推。
Each time we add a single qubit, we double the number of combinations that we can work with in superposition at the same time.
每次我们增加一个量子比特，我们需要同时处理的叠加状态的组合数量将加倍。
And so when we scale up to work with many qubits, we can work with an exponential number of combinations at the same time.
所以当我们扩大规模，处理很多量子比特时，我们需要同时处理的组合状态数量呈指数型增加。
And this just hints at where the power of quantum computing is coming from.
而这就暗示了量子计算的力量从何而来。
Now, in modern encryption, our secret keys, like the two factors of that larger number,
如今，在现代加密中，我们的密钥，例如大数的分解因子，
they're just long sequences of zeroes and ones.
它们只是0和1的长序列。
To find them, a classical computer must go through every single combination, one after the other,
为了找到它们，一个传统计算机必须实验所有的组合可能，一个接着一个，
until it finds the one that works and breaks our encryption.
直到找到那对可以成功破译加密的组合。
But on a quantum computer, with enough qubits in superposition,
但是在量子计算机中，有了足够多的叠加状态的量子比特，
information can be extracted from all combinations at the same time.
可以在同一时间从所有组合中提取信息。
In very few steps, a quantum computer can brush aside all of the incorrect combinations,
只需几个步骤，一个量子计算机就可以撇开所有不正确的组合，
home in on the correct one and then unlock our treasured secrets.
留住正确的那个，然后解锁我们珍贵的秘密。
Now, at the crazy quantum level, something truly incredible is happening here.
在疯狂的量子级别，着实令人难以置信的事情发生了。
The conventional wisdom held by many leading physicists -- and you've got to stay with me on this one
许多顶尖物理学家所拥有的传统智慧--这点你们得跟上我，
is that each combination is actually examined by its very own quantum computer inside its very own parallel universe.
每个组合实际上是由自己的量子计算机在自己的平行宇宙中检验的。
Each of these combinations, they add up like waves in a pool of water.
每个组合，它们像波浪一样积聚在水池中。
The combinations that are wrong, they cancel each other out.
错误的那些组合，它们相互抵消掉。
And the combinations that are right, they reinforce and amplify each other.
而那些正确的组合，它们加强并相互扩大。
So at the end of the quantum computing program,
所以在量子计算过程结束时，
all that's left is the correct answer, that we can then observe here in this universe.
留下了的就只是我们可以在这个宇宙中看到的正确的答案。
Now, if that doesn't make complete sense to you, don't stress. You're in good company.
如果你没有完全搞懂，不要紧张。有人陪你们。
Niels Bohr, one of the pioneers of this field,
尼尔斯·波尔，这个领域的先驱者之一，
he once said that anyone who could contemplate quantum mechanics without being profoundly shocked, they haven't understood it.
他曾经说过任何认真去思考量子力学而没有被深深震惊到的人，只是还没有理解它。
But you get an idea of what we're up against, and why it's now up to us cryptographers to really step it up.
但是你们已经知道了我们要面对的，以及为什么现在我们的密码学家要加紧准备应对它。
And we have to do it fast, because quantum computers, they already exist in labs all over the world.
而且我们必须行动迅速，因为量子计算机已经存在于世界各地的实验室中。
Fortunately, at this minute, they only exist at a relatively small scale,
幸运的是，目前，它们仅以相对较小的规模存在，
still too small to break our much larger cryptographic keys. But we might not be safe for long.
规模尚无法攻破我们那些数量庞大的加密密钥。但是我们安全不了太久了。
Some folks believe that secret government agencies have already built a big enough one, and they just haven't told anyone yet.
有些人认为秘密政府机构已经建立了一个足够大的量子计算机，只是他们还没有告诉任何人。
Some pundits say they're more like 10 years off. Some people say it's more like 30.
一些专家说，还有十年时间。一些人说更有可能是30年。
You might think that if quantum computers are 10 years away,
你们可能认为如果我们距离量子计算机还有十年之远，
surely that's enough time for us cryptographers to figure it out and to secure the internet in time.
我们密码学家肯定还有足够的时间可以想出办法来及时保护我们的网络。
But unfortunately, it's not that easy. Even if we ignore the many years that it takes to standardize and deploy
但是不幸的是，没有那么容易。即使我们忽略进行标准化和部署所要花费的多年时间，
and then roll out new encryption technology, in some ways we may already be too late.
然后推出新的加密技术，在某些方面，我们可能已经来不及了。
Smart digital criminals and government agencies
精明的数字犯罪分子和政府机构
may already be storing our most sensitive encrypted data in anticipation for the quantum future ahead.
可能已经抢在量子计算机大规模应用之前，开始存储我们最敏感的机密数据了。
The messages of foreign leaders, of war generals or of individuals who question power, they're encrypted for now.
外国领导人，打仗的将军，或者质疑权力的个人，他们的信息现在是加密的。
But as soon as the day comes that someone gets their hands on a quantum computer,
但是只要那一天到来，有人有能力操作量子计算机，
they can retroactively break anything from the past.
他们就可以追溯性地破解过去的一切信息。
In certain government and financial sectors or in military organizations,
在某些政府和金融部门，或在军事机构中，
sensitive data has got to remain classified for 25 years.
敏感数据必须保密25年。
So if a quantum computer really will exist in 10 years,
所以如果量子计算机真的在十年后出现，
then these guys are already 15 years too late to quantum-proof their encryption.
那么这些人晚了15年，已经来不及应对量子危机。
So while many scientists around the world are racing to try to build a quantum computer,
所以当世界各地的科学家竞相尝试建造量子计算机时，
us cryptographers are urgently looking to reinvent encryption to protect us long before that day comes.
我们密码学家正迫切重塑我们的加密系统，以在那天到来之前保护我们。
We're looking for new, hard mathematical problems.
我们正在寻找新的数学难题。
We're looking for problems that, just like factorization, can be used on our smartphones and on our laptops today.
我们正在找像数字分解那样的难题，可以用在我们如今的智能手机和电脑上。
But unlike factorization, we need these problems to be so hard that they're even unbreakable with a quantum computer.
但是不同于数字分解，我们需要这个难题足够难，难到它不能被量子计算机破解。
In recent years, we've been digging around a much wider realm of mathematics to look for such problems.
最近几年，我们一直在探索更广阔的数学领域，来寻找这样的难题。
We've been looking at numbers and objects
我们一直在看一些数字和对象，
that are far more exotic and far more abstract than the ones that you and I are used to, like the ones on our calculators.
它们要比你我习惯所见更加奇特、比计算器上的那些抽象得多。
And we believe we've found some geometric problems that just might do the trick.
而且我们相信我们已经找到了一些几何问题，可能会有帮助。
Now, unlike those two- and three-dimensional geometric problems that we used to have to try to solve with pen and graph paper in high school,
它不像那些我们在高中时用图纸和笔解决的二维或三维几何问题，
most of these problems are defined in well over 500 dimensions.
它们大多数定义在500个维度以上。
So not only are they a little hard to depict and solve on graph paper,
所以它们不只在草纸上难以描述和解决，
but we believe they're even out of the reach of a quantum computer.
而且我们相信它们超出了量子计算机的计算范围。
So though it's early days,
所以虽然现在还早，
it's here that we are putting our hope as we try to secure our digital world moving into its quantum future.
但此时此刻，我们希望在步入量子未来时，可以确保我们数字世界的安全。
Just like all of the other scientists,
就像所有其他的科学家一样，
we cryptographers are tremendously excited at the potential of living in a world alongside quantum computers.
我们密码学家对于未来与量子计算机一起生活的世界感到非常兴奋。
They could be such a force for good.
这可能是正义的力量。
But no matter what technological future we live in, our secrets will always be a part of our humanity.
但是无论未来我们有什么样的技术，我们的秘密都将一直是我们人性的一部分。
And that is worth protecting. Thanks.
而它们值得被保护。谢谢。