(单词翻译:单击)
You've just captured the intel and now you have to get it back to the CIA, ASAP.
你已获得情报，请尽快返回中央情报局。
You have the latest encryption, but there's still a chance the network could be compromised, and there's no way to know. Do you risk it?
虽然你已掌握最新加密，但仍有可在不知情的情况下被互联网盗用。你会冒这个险么？
This scenario could be from a spy thriller or a video game, but it's not totally absurd.
虽然这个场景可能来源于间谍片或一款视频游戏，但这种情节并不是无稽之谈。
In fact, scientists across the globe are working on a solution to this very problem.
事实上，全球科学家都在致力于解决这个问题。
And this week, physicists at Princeton and the Australian National University have made some progress.
就在本周，普林斯顿和澳大利亚国立大学在这个问题上取得了一些进展。
In a paper published in the journal Nature Physics, they announced that they're a little closer to making a long-range quantum internet a reality.
他们在《自然物理学》杂志上所发表的一篇论文称，他们离将远程量子互联网变为现实的目标更近了一步。
A quantum what? Alright, we're going to need to take a step back here.
量子什么？好吧，让我们先回到上一个话题。
A quantum internet, which would encode information using tiny particles, could be the perfect way to send messages that are completely secure.
量子互联网，能使用微粒编码信息，这可能是安全传递信息的最佳方法。
You've probably heard about quantum computing, which uses quantum bits, or qubits, instead of the ones and zeroes our regular computers use.
你可能听过用使用量子比特进行的量子计算代替那些使用‘1’和‘0’进行计算的普通电脑。
Qubits are special because they're based on the physical properties of particles, like an electron's spin.
量子比特的特别之处在于他们是基于粒子的物理性质，比如电子的自旋。
An electron's spin can be up or down, but because this is quantum mechanics, where everything is complicated and weird to think about,
电子自旋可向上或向下，但是因为自旋是量子力学，而在量子力学中所有事物都是复杂且怪异的，
its spin can also be up and down at the same time.
因此，自旋可以同时向上向下。
That's what's known as superposition, where particles like electrons or photons are in two opposite states at once.
这就是所谓的迭加，在迭加中，如电子或光子这样的粒子会同时处于两种相反的状态。
It makes no sense in the context of how we normally experience the world, but that's just the tip of the very, very strange quantum mechanical iceberg.
在我们所处的世界中这完全说不通，而这只是怪异量子物理学的冰山一角。
On the scale of tiny particles, the classic principles of science start to break down, and things happen that seem like they should be impossible.
以微粒的规模，科学的经典原则要开始瓦解了，很多事情将朝着似乎不可能的方向发展。
But based on a lot of experiments and math, we know they are happening.
但是基于众多的实验和数学理论，我们知道它们确实正在发生。
So even though it can be hard to wrap our brains around it,
所以即使我们的大脑还转不过来，
we've just had to accept that particles can do things like be in two opposite states at once.
我们也不得不接受这个事实：粒子可以同时处于两种相反的状态。
And with quantum computing, we're using this weirdness to our advantage in two main ways.
通过量子计算，我们可以将这种对我们有利的怪异状态运用于两种主要方式。
First, you can encode more information in a qubit than in a conventional bit.
第一，相对于传统比特，你可以在量子比特中编码更多信息。
Two conventional bits, for instance, will have one of four possible values: 00, 01, 10, or 11.
例如，两个传统比特可以出现四种可能数值中的一种：00、01、10、11。
Each qubit, though, can be both a zero and a one at the same time, so two qubits can be all four possibilities at once.
每个量子比特可以同时是‘0’和‘1’，因此，两个量子比特可以同时产生四种可能数值。
As you add more qubits, the amount of information you can store and process goes up incredibly fast.
当你加入更多量子比特，你可以储存和处理的信息量会快速增长。
With a 300 qubit computer, you could do more calculations at once than there are atoms in the universe.
通过一台300量子比特计算机，你可以同时处理比宇宙中原子数量还多的计算。
Basically, a big enough quantum computer would be infinitely more powerful than the best supercomputer we could ever build the regular way,
从根本上来说，一台足够大的量子计算机相比我们通常可组建的最好的超级计算机来说，威力无限，
and it's why physicists have been geeking out over this ever since they realized it was theoretically possible.
这也是为什么当物理学家们意识到量子计算机在理论上的可能性后，一直致力于这项研究的原因。
The second main advantage of quantum computing is that you can use qubits to send information in a way that's inherently secure.
量子计算的第二个优势是使用量子比特传递信息自带安全属性。
When you encrypt information, you jumble it up so that when you send it, anyone listening in won't be able to decipher the message.
当你将信息译成密码，传递信息时，你打乱这条密码，任何听取信息的人都无法破译其中的消息。
But the person you're sending it to, who you actually want to read it, needs to be able to decode it, so you send them a key they can use to decrypt the message.
但是那个真正的信息接收人，那个你真正想传达的人需要破译这条消息，因此，你将用于破解消息的密钥发送给他们。
Problem is, if someone's eavesdropping on the key, they'll be able to decode it also.
问题是，如果有人窃取到了这个密钥，他们不是也能够破解信息了么。
There are lots of ways cryptographers try to get around this, but they all have some flaws, and in theory could be hacked eventually.
译解密码者尝试多种方法解决这个问题，但是这些方法都存在缺陷，而且在理论上，最终都会被侵入。
Quantum computing, on the other hand, might be the perfect answer because of another weird rule of quantum mechanics:
另一方面，量子计算，可能因量子力学另一条诡异的规则，成为了这一问题的最佳答案：
When you measure something like an electron's spin, the act of taking the measurement actually changes some of the electron's properties.
当你测量电子自旋时，事实上测量这一行为就改变了电子的一些性质。
So if you use qubits to send your friend Bob a key, and your archnemesis Eve intercepts any of the particles before sending them along to Bob,
因此，如果你利用量子比特向你的朋友Bob传递一个密钥，在将密钥传送给Bob前，你的死对头Eve窃取了任何一个粒子，
you and Bob will be able to tell that someone messed with the qubits before he got them.
你和Bob将能辨别出有人干扰了量子比特。
In other words: no one can eavesdrop on your key without you knowing about it.
换句话说：没有人能够在你不知情的情况下，窃取你的密钥。
This is next-order encryption, and we'd like to take advantage of it.
这就是下一位数的加密，我们想要运用这一点。
But that means having more than one quantum computer, and hooking them up over long distances.
但是这就意味着需要不仅一台量子计算机并且将它们远距离连接。
Basically, we want to build a quantum internet. And that's where this new research comes in.
大体上来讲，我们想要建造一个量子互联网。在量子互联网中进行这项新研究。
We already have a massive global network of fiber optic cables,
我们已经拥有了巨大的光纤电缆全球网络，
so it'd be great to piggyback on our existing infrastructure as we build the internet of the future.
因此，如果在我们建立未来互联网时，能够借助现有的基础设施，就再好不过了。
And fiber optic cables are a pretty good choice, because you can use photons of light as qubits. But there are two big challenges.
光纤电缆也是个不错的选择，因为你可以利用光子的光作为量子比特。但是这仍面临两个巨大的挑战。
First, to use those fiber optic cables, you need to transmit photons with a certain wavelength.
第一，要使用那些光纤电缆，你需要运用某种波长发送光子。
Second, qubits are super fragile. If anything interferes with the particles before you transfer your message, you've lost your data.
第二，量子比特超级脆弱。如果在你传送信息之前，粒子受到任何干扰，都会导致数据的丢失。
So you need to keep your qubits stable.
所以你需要保持量子比特的稳定。
We've already discovered how to use certain materials to store quantum information for long enough to send it through a network,
我们已经发现了如何使用某种材料长时间储存量子信息使其能通过网络传输，
but they don't work on the right wavelength for our fiber optic cables.
但是他们无法在光纤电缆的波长中运作。
And the materials that are compatible with those cables can store information for only a fraction of a second. That's too short.
并且虽然这种材料与那些可储存信息电缆相匹配，但是储存时间不足一秒，这也太短了。
To solve this problem, the Australian team wanted to find a way to lengthen that time.
为了解决这一问题，澳大利亚团队希望找到一种能够延长时间的方法。
So they started experimenting with a crystal that had some erbium in it.
因此，他们开始对一种含有铒的晶体进行实验。
Erbium is a rare earth metal, and a crystal with erbium ions in it can work on a wavelength that matches fiber optic cables,
铒是一种稀土金属，含有铒离子的晶体可以在一种与光纤电缆相匹配的波长中运作，
but it can only store quantum information for short bursts.
但是，它仅能在短脉冲中储存量子信息。
To increase that timeframe, the group applied a super-strong 7 Tesla magnet.
为了延长时间框架，这个团队运用了超强7特斯拉磁体。
That's the strength of the most powerful MRI machines.
这是最强核磁共振成像机器才能用到的力量。
Magnets are helpful because they can freeze electrons in the crystal in place, which keeps them from interfering with and destroying the data.
磁体是有所帮助的，因为它们可以凝固晶体中的电子，使数据不受它们的干扰，避免遭到破坏。
And it worked! The magnet increased the crystal's storage time to 1.3 seconds.
这次真的成功了！磁体将晶体的储存时间延长到了1.3秒。
Now, that might not seem very long, but it's a 10,000-fold improvement over what scientists could do before — and it's good enough for a quantum internet.
虽然储存时间也不是很长，但是这比之前科学家们可持续的时间长了10000倍——这对量子互联网而言足够了。
Other experts have estimated that with quantum repeaters to boost the signals, you need storage times of just 1 second to send messages 1000 kilometers.
其他专家估计量子中继器能够增强信号，这样仅需要1秒的储存时间就能够将信息传递至1000千米。
So, where's our quantum internet?
那么，我们的量子互联网在哪呢？
Any kind of widespread network is still a ways off.
任何形式的广泛互联网都是一条遥远的路途。
For one thing, the Australian setup required very low temperatures to work: 1.4 Kelvin, or -272 Celsius.
首先，澳大利亚的设备所要求的工作温度非常低：1.4K或者零下272摄氏度。
That's seriously cold, and seriously expensive to maintain.
这真的是非常寒冷了，而且要保持这个温度所需支出非常昂贵。
And, of course, there's that strong magnetic field.
当然，还要一个非常强的磁场。
The researchers think their material will still work with a less powerful 3 Tesla magnet, but it's not like that's nothing.
研究员认为他们的材料即使是用稍逊一筹的3特斯拉磁体也能运作，但是事实并非如此。
Think of a more typical MRI machine instead of the most advanced. Not exactly chump change.
就像用一台更加传统的MRI机代替最强劲的MRI机器。这可不是一个小小的改变。
But even if we solve those problems, quantum networks might never be used for things like watching this video,
但是即使我们解决了这些问题，量子互联网可能永远都不会被运用于看视频，
or to execute run-of-the-mill Google searches, like 'quantum repeater' or 'erbium crystal'.
或处理一般的谷歌搜索这类小事上，比如搜索‘量子中继器’或‘铒晶体’。
They'll be reserved for super-secret situations when you want your communication to be absolutely secure.
它们可能会被留用于绝密情况，如需要确保对话绝对安全的情况。
So, maybe your banking, but probably more like high-level international intelligence. Basically, spy stuff.
所以，也许用于你的银行业务，更有可能是用于高层国际情报。主要就是用于间谍工作。
But no matter who ends up using it, the quantum internet will be a major upgrade for the world of cryptography.
但是不论最后用于哪个方面，量子互联网将是密码学世界的一个重要升级。
Thanks for watching this episode of SciShow News,
感谢收看这期的科学秀，
and if you want to learn more about quantum computers, you can check out an earlier episode we did about another amazing quantum computing breakthrough.
如果你想了解更多关于量子计算机的知识，你可以点击收看我们之前关于另一个量子计算大突破的视频。
