There is something about physics

物理學中有件事情

that has been really bothering me since I was a little kid.

自幼時就一直非常困擾我。

And it's related to a question

近百年來科學家思索著這個問題

that scientists have been asking for almost 100 years,

但沒有答案。

with no answer.

自然界中最小的東西， 即量子世界的微粒子，如何與

How do the smallest things in nature,

自然界中最大的東西，即星系裡 以重力連結的行星和恆星相對應呢？

the particles of the quantum world,

童年的我，為這樣的問題搜索枯腸。

match up with the largest things in nature --

我操作顯微鏡和電磁鐵，

planets and stars and galaxies held together by gravity?

我研讀微物質的力學

As a kid, I would puzzle over questions just like this.

和量子力學，

I would fiddle around with microscopes and electromagnets,

讚嘆其描述和我們的觀察 是如此的相應。

and I would read about the forces of the small

我也觀看星星，

and about quantum mechanics

閱讀我們所知的重力，

and I would marvel at how well that description matched up

想當然耳，大和小的兩個系統 必然有種精美而優雅的相應方式。

to our observation.

但可惜卻沒有。

Then I would look at the stars,

根據書本，

and I would read about how well we understand gravity,

我們很懂這兩個各別的系統，

and I would think surely, there must be some elegant way

但是一旦嘗試以數學模式來連結，

that these two systems match up.

就完全行不通了。

But there's not.

百年來，

And the books would say,

我們對於如何解決 這基本的物理問題一籌莫展，

yeah, we understand a lot about these two realms separately,

沒有可以支持的證據。

but when we try to link them mathematically,

對於小老弟在下──

everything breaks.

小小、好奇、不信服的詹姆斯──

And for 100 years,

這是絕對不可接受的。

none of our ideas as to how to solve this basically physics disaster,

今天的我，仍是個不易信服的小孩。

has ever been supported by evidence.

時間快轉到 2015 年十二月，

And to little old me --

我重拍額頭，

little, curious, skeptical James --

突然有個物理世界裡的靈光一閃。

this was a supremely unsatisfying answer.

始自我們在歐洲核子研究組織 CERN 看到有趣的數據：

So, I'm still a skeptical little kid.

它們隱射一種新的粒子，

Flash-forward now to December of 2015,

暗示一個可能不同凡響的解答。

when I found myself smack in the middle

我仍是個不信服的小子，

of the physics world being flipped on its head.

現在也是個找尋粒子的人。

It all started when we at CERN saw something intriguing in our data:

我是 CERN 的物理學家， 用「大型強子對撞機（LHC）」，

a hint of a new particle,

一具到目前為止所安裝過的 最大型的科學實驗儀器。

an inkling of a possibly extraordinary answer to this question.

這是條在法國和瑞士邊界間的 二十七公里長的隧道，

So I'm still a skeptical little kid, I think,

埋在一百公尺深的地下。

but I'm also now a particle hunter.

隧道裡，

I am a physicist at CERN's Large Hadron Collider,

我們用比外太空更低溫的超導磁體

the largest science experiment ever mounted.

把質子加速到接近光速，

It's a 27-kilometer tunnel on the border of France and Switzerland

使它們每秒彼此互相撞擊數百萬次，

buried 100 meters underground.

收集碰撞的碎片，

And in this tunnel,

搜索新的、尚未被發現的基本粒子。

we use superconducting magnets colder than outer space

其設計和施工費時幾十年，

to accelerate protons to almost the speed of light

全球各地數以千計的 物理學家通力合作，

and slam them into each other millions of times per second,

在 2015 年夏天，

collecting the debris of these collisions

我們不眠不休地讓 LHC 開始運轉，

to search for new, undiscovered fundamental particles.

實驗用到人類前所未有的 最高撞擊能量。

Its design and construction took decades of work

高能量至關重要，對粒子而言，

by thousands of physicists from around the globe,

能量和質量轉換守恆，

and in the summer of 2015,

質量只是個自然界擺在那兒的數字。

we had been working tirelessly to switch on the LHC

為要發現新的粒子，

at the highest energy that humans have ever used in a collider experiment.

我們必須耗費更多的能量。

Now, higher energy is important

因此，我們必須建造更大、 更耗能的對撞機；

because for particles, there is an equivalence

而世界上最大的對撞機

between energy and particle mass,

是 LHC。

and mass is just a number put there by nature.

然後，我們碰撞質子 千萬億（10 的 24 次方）次

To discover new particles,

我們經年累月慢慢地收集資料。

we need to reach these bigger numbers.

或許新的粒子會以突起的形狀 呈現在資料的平滑線外──

And to do that, we have to build a bigger, higher energy collider,

稍微偏離預期值，

and the biggest, highest energy collider in the world

小小群集的數據點， 使得平滑的線不再那麼地平滑。

is the Large Hadron Collider.

例如，這個凸起，

And then, we collide protons quadrillions of times,

2012 年累月的數據採集後，

and we collect this data very slowly, over months and months.

導致發現了「希格斯粒子」，

And then new particles might show up in our data as bumps --

或稱「希格斯玻色子」，

slight deviations from what you expect,

和因證明它存在而獲得的諾貝爾奬。

little clusters of data points that make a smooth line not so smooth.

2015 年看到的能量凸起

For example, this bump,

代表人類發現新粒子的絕佳機會，

after months of data-taking in 2012,

這些長期謎題的新解答，

led to the discovery of the Higgs particle --

因它所耗的能量幾乎是 發現希格斯玻色子時耗能的兩倍。

the Higgs boson --

我的許多同事 整個職涯都在追尋此刻，

and to a Nobel Prize for the confirmation of its existence.

坦率地說，對好奇的我而言，

This jump up in energy in 2015

這是我一輩子等待的時刻。

represented the best chance that we as a species had ever had

2015 年是跳下去做， 不回頭的時刻。

of discovering new particles --

因此於 2015 年六月，

new answers to these long-standing questions,

LHC 又運轉了。

because it was almost twice as much energy as we used

同事和我屏息、緊張又興奮，

when we discovered the Higgs boson.

終於看到質子以有史以來 最高的能量互撞。

Many of my colleagues had been working their entire careers for this moment,

鼓掌，開香檳，慶祝。

and frankly, to little curious me,

這是科學的里程碑，

this was the moment I'd been waiting for my entire life.

我們不知道會在 這全新的數據裡找到什麼。

So 2015 was go time.

數週後，我們發現了凸起的數據。

So June 2015,

凸起雖不算大，

the LHC is switched back on.

但已足以讓人訝異。

My colleagues and I held our breath and bit our fingernails,

從 1 到 10 的訝異程度，

and then finally we saw the first proton collisions

10 代表你已發現了新的粒子，

at this highest energy ever.

這是個程度大約 4 的訝異。

Applause, champagne, celebration.

（笑聲）

This was a milestone for science,

我花了無數的時間秘密開會，

and we had no idea what we would find in this brand-new data.

和同事辯論這個小凸起，

And then a few weeks later, we found a bump.

努力在雞蛋裡挑骨頭，

It wasn't a very big bump,

看它是否經得起最嚴厲的檢視。

but it was big enough to make you raise your eyebrow.

即使在數月不眠不休地工作後──

But on a scale of one to 10 for eyebrow raises,

不回家，而是睡在辦公室，

if 10 indicates that you've discovered a new particle,

以糖果零嘴當晚餐，

this eyebrow raise is about a four.

大桶大桶地喝咖啡──

(Laughter)

物理學家就是 把咖啡變成圖表的機器──

I spent hours, days, weeks in secret meetings,

（笑聲）

arguing with my colleagues over this little bump,

這個小凸起並未消失。

poking and prodding it with our most ruthless experimental sticks

幾個月後，

to see if it would withstand scrutiny.

我們向世界展示了這個小凸起 和一個非常明確的信息：

But even after months of working feverishly --

這個小凸起有趣，但是不明確，

sleeping in our offices and not going home,

讓我們收集更多的數據 並持續關注它。

candy bars for dinner,

我們試圖非常冷靜地看待它。

coffee by the bucketful --

儘管如此，世界隨它起舞。

physicists are machines for turning coffee into diagrams --

新聞界喜愛它。

(Laughter)

人們說它讓他們想起發現 希格斯玻色子路上的那個小凸起。

This little bump would not go away.

更棒的是，我的理論派同事們──

So after a few months,

我喜歡我的理論派同事們──

we presented our little bump to the world with a very clear message:

我的理論派同事們寫了五百篇 關於這個小凸起的文章。

this little bump is interesting but it's not definitive,

（笑聲）

so let's keep an eye on it as we take more data.

粒子物理學的世界已然翻轉。

So we were trying to be extremely cool about it.

這個小凸起的什麼特點

And the world ran with it anyway.

使得成千上萬的物理學家 熱血沸騰呢？

The news loved it.

這個小凸起獨一無二。

People said it reminded them of the little bump

這個小凸起顯示

that was shown on the way toward the Higgs boson discovery.

我們看到了意料之外的大量碰撞，

Better than that, my theorist colleagues --

碰撞後只殘留兩個光子，

I love my theorist colleagues --

兩個光粒子。

my theorist colleagues wrote 500 papers about this little bump.

這相當罕見。

(Laughter)

粒子碰撞不像汽車碰撞。

The world of particle physics had been flipped on its head.

碰撞的規則不同。

But what was it about this particular bump

當兩個粒子以接近光速的速度互撞，

that caused thousands of physicists to collectively lose their cool?

行為就由量子世界的規則所掌控。

This little bump was unique.

在量子世界中，

This little bump indicated

這兩個粒子能短暫地 創造一個新粒子，

that we were seeing an unexpectedly large number of collisions

只瞬間存在，

whose debris consisted of only two photons,

頃刻後分裂成其他粒子， 並擊中我們的偵測器。

two particles of light.

想像一下兩輛汽車互撞， 汽車在相撞的當下消失，

And that's rare.

原地出現了一輛自行車──

Particle collisions are not like automobile collisions.

（笑聲）

They have different rules.

那輛自行車緊接著爆炸， 變成兩個滑板，

When two particles collide at almost the speed of light,

撞到我們的偵測器。

the quantum world takes over.

（笑聲）

And in the quantum world,

當然不是字面上的撞上，

these two particles can briefly create a new particle

偵測器可是很貴的啊。

that lives for a tiny fraction of a second

僅僅兩個光子撞擊偵測器的 事件非常地罕見。

before splitting into other particles that hit our detector.

由於光子具有量子的特性，

Imagine a car collision where the two cars vanish upon impact,

新粒子，也就是這些虛搆的自行車， 出現的機率相當罕見，

a bicycle appears in their place --

只產生兩個光子的新粒子非常罕見。

(Laughter)

但是有一選項極可能發生，

And then that bicycle explodes into two skateboards,

和一個長期存在的未解題有關，

which hit our detector.

就是那個自幼就困擾我的重力問題。

(Laughter)

或許你認為重力強而有力，

Hopefully, not literally.

但是相較於自然界的其他力量， 它其實超弱的。

They're very expensive.

當我跳起時，能夠短暫地擺脫重力，

Events where only two photons hit out detector are very rare.

但我卻無法用手撿起一粒質子。

And because of the special quantum properties of photons,

相較於自然界的其他力量， 重力的強度如何呢？

there's a very small number of possible new particles --

是 10 的負 39 次方。

these mythical bicycles --

小數點之後跟著 39 個零。

that can give birth to only two photons.

更糟的是，

But one of these options is huge,

所有其他已知的自然界力量都可被 所謂的「標準模型」完美地描述。

and it has to do with that long-standing question

那是我們目前描述自然界 最小尺度的最佳模型。

that bothered me as a tiny little kid,

坦白說，

about gravity.

那是人類最大的成就之一，

Gravity may seem super strong to you,

重力標準模型不存在是唯一的例外。

but it's actually crazily weak compared to the other forces of nature.

難以置信。

I can briefly beat gravity when I jump,

彷彿大部分的重力消失不見了。

but I can't pick a proton out of my hand.

我們察覺到少許重力，

The strength of gravity compared to the other forces of nature?

但其他的部分呢？

It's 10 to the minus 39.

沒有人知道。

That's a decimal with 39 zeros after it.

但有個理論提供了瘋狂的解釋。

Worse than that,

你們和我──

all of the other known forces of nature are perfectly described

包括坐在後面的諸位──

by this thing we call the Standard Model,

我們生活在三度空間裡。

which is our current best description of nature at its smallest scales,

希望這並無爭議。

and quite frankly,

（笑聲）

one of the most successful achievements of humankind --

所有已知的粒子也存在三度空間裡。

except for gravity, which is absent from the Standard Model.

事實上，粒子只是別名，

It's crazy.

是三度空間裡的激發；

It's almost as though most of gravity has gone missing.

空間中的局部擺動。

We feel a little bit of it,

更重要的是，我們用來描述 所有這些玩意的數學

but where's the rest of it?

全都假設只有三度空間。

No one knows.

但數學就是數學， 我們可以隨意擺弄數學。

But one theoretical explanation proposes a wild solution.

長久以來，人們一直悠遊於 更多維度的數學中，

You and I --

但僅僅是個抽象的數學概念而已。

even you in the back --

我的意思是，看看你們的周圍── 坐在後面的諸位，請環顧四周──

we live in three dimensions of space.

顯然只有三度空間。

I hope that's a non-controversial statement.

但，倘若事實並非如此呢？

(Laughter)

如果消失的重力

All of the known particles also live in three dimensions of space.

流入了我們看不見的第四度空間呢？

In fact, a particle is just another name

如果重力和其他的力量同樣有力，

for an excitation in a three-dimensional field;

前提是增加維度來看待它;

a localized wobbling in space.

如果你我目前體驗到的重力 只是一小部分，

More importantly, all the math that we use to describe all this stuff

所以才會看起來這麼弱呢？

assumes that there are only three dimensions of space.

假如這是真的，

But math is math, and we can play around with our math however we want.

我們就必須擴大粒子的標準模型， 包括其他的粒子，

And people have been playing around with extra dimensions of space

「超維度的重力子」，

for a very long time,

存在另一度空間的重力子。

but it's always been an abstract mathematical concept.

我注意到你們的臉上的表情。

I mean, just look around you -- you at the back, look around --

你們該問我：

there's clearly only three dimensions of space.

「要怎樣去測試 這瘋狂而科幻的想法呢？

But what if that's not true?

我們到底身處在三度空間裡啊！」

What if the missing gravity is leaking into an extra-spatial dimension

老法子，

that's invisible to you and I?

使兩個光子互撞──

What if gravity is just as strong as the other forces

（笑聲）

if you were to view it in this extra-spatial dimension,

碰撞反射到或許存在的 多度空間已經夠難了，

and what you and I experience is a tiny slice of gravity

遑論頃刻間造出超維度的重力子，

make it seem very weak?

並且撞擊到三度空間的 LHC，

If this were true,

又再分裂為兩個光子，

we would have to expand our Standard Model of particles

兩個光粒子。

to include an extra particle, a hyperdimensional particle of gravity,

這假設的超維度重力子，

a special graviton that lives in extra-spatial dimensions.

唯一可能假設的新粒子，

I see the looks on your faces.

具有特別的量子空間特性，

You should be asking me the question,

能產生我們這個小小的二光子凸起。

"How in the world are we going to test this crazy, science fiction idea,

因此，解釋重力的奧秘，

stuck as we are in three dimensions?"

和發現另一度空間的可能性──

The way we always do,

現在或許你們稍稍明白了

by slamming together two protons --

為何成千上萬的怪胎物理學家

(Laughter)

會因小小的兩光子凸起而集體激動。

Hard enough that the collision reverberates

這樣的發現將會改寫教科書。

into any extra-spatial dimensions that might be there,

但請記住，

momentarily creating this hyperdimensional graviton

我們這些當時真正做實驗的人 傳達的訊息非常的清楚：

that then snaps back into the three dimensions of the LHC

我們需要更多的數據。

and spits off two photons,

有了更多的數據，

two particles of light.

這小小的凸起可能會成為 漂亮、清新的諾貝爾獎──

And this hypothetical, extra-dimensional graviton

（笑聲）

is one of the only possible, hypothetical new particles

或者增加的數據 會填滿凸起周邊的空間，

that has the special quantum properties

使它成為平滑、順暢的線條。

that could give birth to our little, two-photon bump.

因此我們收取更多的數據，

So, the possibility of explaining the mysteries of gravity

又經過幾個月，增加了五倍的數據，

and of discovering extra dimensions of space --

我們的小凸起

perhaps now you get a sense

成為平滑的線條。

as to why thousands of physics geeks collectively lost their cool

新聞報導了「大失望」、 「消逝的希望」，

over our little, two-photon bump.

以及粒子物理學家們很「悲傷」。

A discovery of this type would rewrite the textbooks.

根據報導的語氣，

But remember,

你們會認為我們已經決定 關掉 LHC，打道回府了。

the message from us experimentalists

（笑聲）

that actually were doing this work at the time,

但我們沒那樣做。

was very clear:

為什麼不呢？

we need more data.

如果我沒發現新粒子── 而我的確沒發現──

With more data,

如果我沒發現新粒子， 怎麼還在這裡對你們演講？

the little bump will either turn into a nice, crisp Nobel Prize --

我怎麼沒羞恥地低著頭，

(Laughter)

躲回家裡去呢？

Or the extra data will fill in the space around the bump

粒子物理學家是探索者。

and turn it into a nice, smooth line.

我們繪製很多的圖。

So we took more data,

暫時先不管 LHC，讓我這樣來描述：

and with five times the data, several months later,

想像你是個太空探險家，

our little bump

飛到一個遙遠的行星去搜索外星人。

turned into a smooth line.