Imagine that you are in Las Vegas,

咱們來玩個遊戲。

in a casino,

想像你在拉斯維加斯，

and you decide to play a game on one of the casino's computers,

在一間賭場裡，

just like you might play solitaire or chess.

你決定在其中一台電腦上玩遊戲，

The computer can make moves in the game, just like a human player.

就像是玩紙牌或是下棋。

This is a coin game.

電腦也能移動遊戲中的棋子， 和人類玩家一樣。

It starts with a coin showing heads,

這是一個硬幣遊戲。

and the computer will play first.

一開始，有一枚正面朝上的硬幣，

It can choose to flip the coin or not,

開局後，電腦先玩。

but you don't get to see the outcome.

它可以選擇是否拋擲這枚硬幣，

Next, it's your turn.

但你不會知道結果如何。

You can also choose to flip the coin or not,

接著就輪到你。

and your move will not be revealed to your opponent, the computer.

你也可以選擇是否拋擲這枚硬幣，

Finally, the computer plays again, and can flip the coin or not,

你的對手，也就是電腦， 同樣不會知道這一輪的結果。

and after these three rounds,

最後，又輪到電腦 選擇是否拋擲硬幣，

the coin is revealed,

經過三輪遊戲之後，

and if it is heads, the computer wins,

硬幣的狀態被揭示出來，

if it's tails, you win.

如果是正面朝上，就是電腦贏，

So it's a pretty simple game,

如果是反面朝上，就是你贏。

and if everybody plays honestly, and the coin is fair,

這是個很簡單的遊戲，

then you have a 50 percent chance of winning this game.

如果大家都不作弊， 且硬幣也是均勻的，

And to confirm that,

那麽你就有 50% 的機會獲勝。

I asked my students to play this game on our computers,

為了確認這一點，

and after many, many tries,

我讓我的學生用我們的 電腦來玩這個遊戲，

their winning rate ended up being 50 percent, or close to 50 percent,

在嘗試非常非常多次之後，

as expected.

他們的勝率最後是 50% 或接近 50%，

Sounds like a boring game, right?

和預期的一樣。

But what if you could play this game on a quantum computer?

聽起來很無聊，對吧？

Now, Las Vegas casinos do not have quantum computers,

但如果你能用量子電腦 來玩這個遊戲，會怎樣？

as far as I know,

拉斯維加斯的賭場可沒有量子電腦，

but IBM has built a working quantum computer.

據我所知是這樣，

Here it is.

但 IBM 已經打造出了一台 能夠正常運轉的量子電腦。

But what is a quantum computer?

就是它。

Well, quantum physics describes

但是，量子電腦是什麼？

the behavior of atoms and fundamental particles,

嗯，量子物理是在描述

like electrons and photons.

原子和基本粒子的行為，

So a quantum computer operates

比如電子和光子。

by controlling the behavior of these particles,

所以，量子電腦的運作方式 在於控制這些粒子的行為，

but in a way that is completely different from our regular computers.

但其做法和普通的電腦完全不同。

So a quantum computer is not just a more powerful version

量子電腦並不只是

of our current computers,

我們目前電腦的加強版，

just like a light bulb is not a more powerful candle.

就好像電燈泡並不是加強版的蠟燭。

You cannot build a light bulb by building better and better candles.

無論如何，蠟燭也不可能變成電燈泡。

A light bulb is a different technology,

電燈泡使用了一種不同的技術，

based on deeper scientific understanding.

它的基礎是更深入的科學理解。

Similarly, a quantum computer is a new kind of device,

同樣地，量子電腦也是一種新裝置，

based on the science of quantum physics,

以量子物理為根據，

and just like a light bulb transformed society,

就如同電燈泡改變了人類社會，

quantum computers have the potential to impact

量子電腦也有潛力影響 我們生活的方方面面，

so many aspects of our lives,

包括我們的安全需求、 我們的醫療保健，甚至網際網路。

including our security needs, our health care and even the internet.

全世界的公司都在打造這類裝置。

So companies all around the world are working to build these devices,

要想看看它有多讓人興奮，

and to see what the excitement is all about,

咱們來用量子電腦玩這個遊戲。

let's play our game on a quantum computer.

我可以從這裡登入到 IBM 的量子電腦，

So I can log into IBM's quantum computer from right here,

也就表示我可以從遠端玩這個遊戲，

which means I can play the game remotely,

你也可以做到。

and so can you.

為了讓你們參與進來，你們可能記得，

To make this happen, you may remember getting an email ahead of time, from TED,

先前有收到 TED 寄的電子郵件，

asking you whether you would choose to flip the coin or not,

信上請你選擇， 如果你在玩這個遊戲，

if you played the game.

是否會選擇拋擲硬幣。

Well, actually, we asked you to choose between a circle or a square.

事實上，我們在信上 是請你選擇圓形或方形。

You didn't know it, but your choice of circle meant "flip the coin,"

你當時並不知道，選擇圓形 就表示「擲硬幣」，

and your choice of square was "don't flip."

選擇方形就表示「不要擲」。

We received 372 responses.

我們收到了 372 個人的回覆。

Thank you.

謝謝你們。

That means we can play 372 games against the quantum computer

那就表示，我們可以用你們的選擇，

using your choices.

跟量子電腦玩 372 場遊戲。

And it's a pretty fast game to play,

這個遊戲一下就結束了，

so I can show you the results right here.

所以我可以把結果呈現在這裡。

Unfortunately, you didn't do very well.

不幸的是，你們的戰績不太好。

(Laughter)

（笑聲）

The quantum computer won almost every game.

量子電腦幾乎全勝。

It lost a few only because of operational errors in the computer.

它輸了幾場，只是因為 電腦中的運算錯誤。

(Laughter)

（笑聲）

So how did it achieve this amazing winning streak?

所以，它是如何取得 這驚人的一連串勝利的？

It seems like magic or cheating,

它就像魔術或作弊一樣，

but actually, it's just quantum physics in action.

但事實上，它只是量子物理的運作。

Here's how it works.

它的運作方式如下。

A regular computer simulates heads or tails of a coin as a bit,

普通電腦用一個位元來 模擬硬幣的正反面，

a zero or a one,

即 0 或是 1，

or a current flipping on and off inside your computer chip.

或記錄當前是否選擇拋擲硬幣， 儲存在你的電腦晶片中。

A quantum computer is completely different.

量子電腦則完全不同。

A quantum bit has a more fluid, nonbinary identity.

一個量子位元更具有 不固定性、非二進制的特質。

It can exist in a superposition, or a combination of zero and one,

它能存在於量子疊加態當中， 即 0 和 1 的組合當中，

with some probability of being zero and some probability of being one.

既有可能是 0，也有可能是 1。

In other words, its identity is on a spectrum.

換言之，它的真面目其實是一個範圍。

For example, it could have a 70 percent chance of being zero

比如，它可能有 70% 的概率是 0，

and a 30 percent chance of being one

30% 的概率是 1，

or 80-20 or 60-40.

或 80% 與 20%， 60% 與 40%等。

The possibilities are endless.

存在無限的可能性。

The key idea here

這裡的關鍵在於，

is that we have to give up on precise values of zero and one

我們得要捨棄「只存在固定的 0 和 1」 的思考方式，

and allow for some uncertainty.

允許不確定性存在。

So during the game,

在遊戲期間，

the quantum computer creates this fluid combination of heads and tails,

量子電腦會創造出正反兩面 （0 和 1）的不固定性組合，

zero and one,

所以，不論玩家選擇什麼，

so that no matter what the player does,

不論擲或不擲硬幣，這種 量子疊加態並不會改變。

flip or no flip,

這有點像是在攪拌兩種液體。

the superposition remains intact.

不論你攪或不攪， 兩種液體都混合在一起。

It's kind of like stirring a mixture of two fluids.

但在它的最後一輪遊戲中，

Whether or not you stir, the fluids remain in a mixture,

量子電腦能分離出 0 和 1，

but in its final move,

將硬幣完美地恢復成正面朝上， 所以你每次都會輸。

the quantum computer can unmix the zero and one,

（笑聲）

perfectly recovering heads so that you lose every time.

如果你覺得這一切十分怪異， 那你一點兒也沒錯。

(Laughter)

普通硬幣並不會以正面 和反面的組合形式存在。

If you think this is all a bit weird, you are absolutely right.

我們在日常生活中並不會經歷

Regular coins do not exist in combinations of heads and tails.

這種不固定的、量子化的現實。

We do not experience this fluid quantum reality

所以，如果量子讓你困惑不解，

in our everyday lives.

別擔心，你其實正在明白它。

So if you are confused by quantum,

（笑聲）

don't worry, you're getting it.

但是，雖然我們沒有 切身體驗量子的不可思議，

(Laughter)

我們可以看到它產生了 非常真實的影響。

But even though we don't experience quantum strangeness,

你們已經親眼看到資料了。

we can see its very real effects in action.

量子電腦會贏，

You've seen the data for yourself.

是因為它利用量子疊加態和不確定性，

The quantum computer won

這些量子特性非常強大，

because it harnessed superposition and uncertainty,

不僅能幫你贏得硬幣遊戲，

and these quantum properties are powerful,

也能用來建造未來的量子科技。

not just to win coin games,

讓我舉三個例子， 說明那些有潛力的科技應用，

but also to build future quantum technologies.

它們有可能改變我們的生活。

So let me give you three examples of potential applications

首先，量子不確定性 可用于私鑰加密，

that could change our lives.

將兩地之間傳輸的訊息進行加密，

First of all, quantum uncertainty could be used to create private keys

因為量子不確定性，

for encrypting messages sent from one location to another

駭客就無法偷偷地複製完整密鑰。

so that hackers could not secretly copy the key perfectly,

他們若想盜用密鑰，

because of quantum uncertainty.

就得打破量子物理的法則。

They would have to break the laws of quantum physics

全世界的銀行和其他機構已經在測試

to hack the key.

這種牢不可破的加密。

So this kind of unbreakable encryption is already being tested by banks

現今，全球使用了超過 170 億個接入網路的裝置。

and other institutions worldwide.

想像一下，量子加密 在未來會有怎樣的影響。

Today, we use more than 17 billion connected devices globally.

第二，量子科技也能轉變 醫療保健和醫學。

Just imagine the impact quantum encryption could have in the future.

比如，在藥物開發中， 設計和分析各種分子

Secondly, quantum technologies could also transform health care and medicine.

是現今很具挑戰性的問題，

For example, the design and analysis of molecules for drug development

這是因為，要精確地描述和計算

is a challenging problem today,

分子中所有原子的全部量子特性，

and that's because exactly describing and calculating

是非常難以計算的， 即使對於超級電腦也同樣。

all of the quantum properties of all the atoms in the molecule

但量子電腦能做得更好，

is a computationally difficult task, even for our supercomputers.

因為它與它試圖模擬的分子一樣，

But a quantum computer could do better,

使用了相同的量子特性來進行計算，

because it operates using the same quantum properties

因此，對於藥物開發， 未來的大規模量子模擬

as the molecule it's trying to simulate.

也許可以為阿茲海默症 之類的疾病找到治療方式，

So future large-scale quantum simulations for drug development

影響成千上萬的人。

could perhaps lead to treatments for diseases like Alzheimer's,

第三，是我最喜愛的量子應用，

which affects thousands of lives.

是將資訊從一個地點 即時傳遞到另一個地點，

And thirdly, my favorite quantum application

但不需要實際傳遞。

is teleportation of information from one location to another

聽起來很科幻，但這是有可能的，

without physically transmitting the information.

因為量子粒子的這些不固定特質

Sounds like sci-fi, but it is possible,

在時間和空間中 可能會糾纏在一起，

because these fluid identities of the quantum particles

以至於當你改變了 其中的某一個粒子，

can get entangled across space and time

就會同時影響到其他粒子的狀態， 這就成了量子通信的「通道」。

in such a way that when you change something about one particle,

在研究實驗室裡已經展示它可行，

it can impact the other,

可能會成為未來量子 網際網路的一部分。

and that creates a channel for teleportation.

我們目前尚無這樣的網路，

It's already been demonstrated in research labs

但我的團隊正在努力實現它，

and could be part of a future quantum internet.

我們會在一台量子電腦上 模擬一個量子網路。

We don't have such a network as yet,

我們已經設計並實現了 一些有趣的、新的通訊協議，

but my team is working on these possibilities,

比如在網路上不同 用戶之間傳輸訊息，

by simulating a quantum network on a quantum computer.

以及高效的文件傳輸，

So we have designed and implemented some interesting new protocols

甚至還有安全的選舉投票。

such as teleportation among different users in the network

因此，我身為量子物理學家， 覺得這非常有意思。

and efficient data transmission

我極力推薦它。

and even secure voting.

（笑聲）

So it's a lot of fun for me, being a quantum physicist.

我們有機會在量子仙境中當探險家。

I highly recommend it.

誰知道接下來我們 會發現什麼新應用。

(Laughter)

當我們打造量子未來時，

We get to be explorers in a quantum wonderland.

我們必須要謹慎且可靠地向前邁進。

Who knows what applications we will discover next.

對我個人來說，

We must tread carefully and responsibly

我認為量子物理並不只是 用來打造量子電腦的工具。

as we build our quantum future.

我認為量子電腦能協助我們 探索大自然的謎題，

And for me, personally,

並更深入地揭示出我們 無法體驗的隱秘世界。

I don't see quantum physics as a tool just to build quantum computers.

這是多麼不可思議，我們人類

I see quantum computers as a way for us to probe the mysteries of nature

對於宇宙的認識 和接觸是相對受限的，

and reveal more about this hidden world outside of our experiences.

我們卻單單靠著想像力和獨創性，

How amazing that we humans,

仍然能觀察到遠遠 高於我們眼界的地方。

with our relatively limited access to the universe,

而宇宙給我們的獎賞

can still see far beyond our horizons

就是讓我們看到它是 多麼有趣、讓人驚奇。

just using our imagination and our ingenuity.

未來，本來就是不確定的，

And the universe rewards us

但對我來說，我很確定， 它是讓人興奮的。

by showing us how incredibly interesting and surprising it is.

謝謝。

The future is fundamentally uncertain,

（掌聲）

and to me, that is certainly exciting.

Thank you.

(Applause)