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  • It's a little known secret

    第二部 萬物之弦

  • But for more than half a century

    優雅的宇宙

  • A dark cloud has been looming over modern science.

    有個不為人所知的秘密

  • Here is the problem

    半個多世紀以來

  • Our understanding of the universe

    近代科學一直為烏雲籠罩

  • Is based on two separate theories.

    問題就在於

  • One is Einstein's general theory of relativity

    我們對宇宙的認知

  • That's a way of understanding The biggest things in the universe,

    是基於兩套不同的理論

  • Things like stars and galaxies.

    一套是愛因斯坦的廣義相對論

  • But the littlest things in the universe,

    描述的是宇宙間最龐大的物質

  • Atoms and subatomic particles,

    像星球跟星系

  • Play by an entirely different set of rules called,

    但宇宙中最微小的物質

  • "quantum mechanics."

    原子跟亞原子粒子

  • These two sets of rules

    則遵循另一種截然不同的定律

  • Are each incredibly accurate in their own domain

    那就是"量子力學"

  • But whenever we try to combine them,

    這兩種定律

  • To solve some of the deepest mysteries in the universe,

    在各自的領域都準確無疑

  • Disaster strikes.

    但一旦嘗試將其合二為一

  • Take the beginning of the universe, the "big bang."

    去探索宇宙的終極奧秘時

  • At that instant a tiny nugget erupted violently.

    災難降臨了

  • Over the next 14 billion years the universe expanded And cooled

    以宇宙誕生之初 也就是"大爆炸"為例

  • into the stars, Galaxies and planets we see today.

    在那一刻 極小的一點猛烈地爆發

  • But if we run the cosmic film in reverse,

    經過140億年 宇宙不斷膨脹 冷卻

  • Everything that's now rushing apart comes back together

    形成了現在所見的恆星 星系和行星

  • So the universe gets smaller, hotter and denser

    但如果我們將宇宙誕生膠片倒轉

  • as we head back to the beginning of time.

    讓所有分裂的物質再度聚合

  • As we reach the big bang,

    宇宙將一直變小 變熱 密度變大

  • When the universe was both enormously heavy And incredibly tiny

    我們將回到時間誕生之初

  • our projector jams.

    抵達大爆炸那一刻時

  • Our two laws of physics, when combined, break down.

    宇宙的質量無窮大而體積無窮小

  • But what if we could unite quantum mechanics

    放映機將停滯於此

  • And general relativity

    一旦這兩套物理定律在此相逢 便會決裂

  • And see the cosmic film in its entirety?

    可要是我們能將量子力學

  • A new set of ideas called "string theory"

    跟廣義相對論成功合併

  • May be able to do that.

    再整體來看宇宙膠片會如何呢

  • And if it's right,

    一種叫做"弦理論"的全新學說

  • It would be one of the biggest blockbusters In the history of science.

    或許能達到目的

  • Someday, string theory may be able to explain all of nature

    如果成功

  • From the tiniest bits of matter

    將是科學史上最轟動事件之一

  • To the farthest reaches of the cosmos,

    日後 弦理論或許能解釋自然界中的一切

  • Using just one ingredient, tiny vibrating strands of energy

    從物質最微小的部分

  • called strings.

    到茫茫宇宙最遙遠的地方

  • But why do we have to rewrite the laws of physics to accomplish this?

    只用一種元素 微小振搗的能量

  • Why does it matter if the two laws That we have are incompatible?

    叫作弦

  • Well, you can think of it like this.

    為何我們要為此改寫物理學定律

  • Imagine you lived in a city ruled not

    兩套定律互不相容有何要緊

  • By one set of traffic laws,

    可以這樣試想

  • But by two separate sets of laws that conflicted with each other.

    假設你住的城市

  • As you can see it would be pretty confusing.

    不是被一種交通規則支配

  • To understand this place, You'd need to find a way

    而是遵循兩套互相矛盾的規則

  • To put those two conflicting sets of laws together

    你就會看到 情形會多混亂

  • Into one all-encompassing set that makes sense.

    為瞭解宇宙 必須找到一種辦法

  • We work on the assumption that there is a theory out there,

    將兩套矛盾的定律

  • And it's our job,

    歸納為一套具有普適性的定律

  • If we're sufficiently smart and sufficiently industrious,

    我們在努力證實存在這樣一套理論

  • To figure out what it is.

    這就是我們的工作

  • We don't have a guarantee

    如果我們足夠聰明和勤奮

  • It isn't written in the stars that we're going to succeed

    就能找到它

  • But in the end

    我們不能保證

  • We hope we will have a single theory

    成功是板上釘釘的事

  • That governs everything.

    但說到底

  • But before we can find that theory,

    我們希望能找到唯一的一套理論

  • We need to take a fantastic journey

    適用於萬事萬物

  • To see why the two sets of laws We have

    在找到那種理論之前

  • conflict with each other.

    我們要先來一次奇幻旅程

  • And the first stop on this strange trip

    看看為何現有的兩套定律

  • Is the realm of very large objects.

    會互相衝突

  • To describe the universe on large scales

    奇妙旅程的第一站

  • We use one set of lawsEinstein's general theory of relativity,

    是龐然大物的國度

  • And that's a theory of how gravity works.

    從宏觀角度描述宇宙時

  • General relativity pictures space as sort of like a trampoline

    我們會用愛因斯坦的廣義相對論

  • A smooth fabric

    它描述了引力是如何運作的

  • that heavy objects like stars and planets can warp and stretch.

    廣義相對論描繪的宇宙像一張蹦床

  • Now, according to the theory,

    一片光滑的結構

  • These warps and curves create what we feel as gravity.

    重物如恆星和行星可以扭曲和擴張

  • That isThe gravitational pull that keeps the earth In orbit around the sun

    根據這套理論

  • Is really nothing more than our planet Following the curves and contours

    這些空間的扭曲讓我們感覺到了所謂的引力

  • that the sun creates in the spatial fabric.

    就是說 保持地球在繞日軌道運行的引力

  • But the smooth, Gently curving image of space

    只是地球在太陽製造的扭曲和波紋

  • predicted By the laws of general relativity

    形成的特殊空間結構上的運動而已

  • is not the whole story.

    但廣義相對論裡預言的

  • To understand the universe on extremely small scales,

    平滑而起伏有致的空間

  • We have to use our other set of laws, quantum mechanics.

    並不是宇宙的全部

  • And as we'll see,

    要以極微觀的角度理解宇宙

  • Quantum mechanics paints a picture of space

    我們得用上另一套定律 量子力學

  • So drastically different from general relativity

    如我們即將所見

  • That you'd think they were describing

    量子力學描繪的宇宙畫卷

  • two completely separate universes.

    與廣義相對論的大不相同

  • To see the conflict between general relativity

    甚至被認為二者描繪的是

  • And quantum mechanics

    兩個完全不同的宇宙

  • We need to shrink way, way, way down in size.

    要瞭解廣義相對論

  • And as we leave the world of large objects behind

    與量子力學之間的矛盾

  • And approach the microscopic realm,

    我們要變得 很小很小

  • The familiar picture of space In which everything behaves predictably

    在我們離開龐然大物的世界

  • Begins to be replaced by a world

    來到微觀粒子領域時

  • With a structure that is far less certain.

    那幅萬物皆可預知的熟悉宇宙圖畫

  • And if we keep shrinking,

    將逐漸被一個

  • Getting billions and billion of times

    結構極不確定的世界取代

  • Smaller than even the tiniest bits of matter

    如果我們繼續縮小

  • Atoms and the tiny particles inside of them

    變得比最小的物質

  • The laws of the very small, quantum mechanics,

    原子和原子中的微觀粒子

  • Say that the fabric of space becomes bumpy and chaotic.

    還小上幾十億倍

  • Eventually we reach a world

    描述微觀世界的量子力學表示

  • So turbulent that it defies common sense.

    這時空間結構將變得波動而混亂

  • Down here,

    最終我們來到了這個

  • Space and time are so twisted and distorted

    喧囂而又違背常理的世界

  • That the conventional ideas of left and right, up and down,

    在這裡

  • Even before and after, break down.

    時間跟空間被扭曲變形

  • There's no way to tell for certain that I'm here,

    傳統概念中的 左右 上下

  • Or here or both places at once.

    甚至是時間的前後 都不復存在

  • Or maybe I arrived here before I arrived here.

    這個世界裡 無法確定我是在這裡

  • In the quantum world you just can't pin everything down.

    在這裡 還是同時處於兩個地方

  • It's an inherently wild and frenetic place.

    又或者我來這裡之前 已經到了這裡

  • The laws in the quantum world

    在量子的世界裡 沒什麼是確知無疑的

  • Are very different from the laws that we are used to.

    這是個放蕩不羈 難以捉摸的地方

  • And is that surprising?

    量子世界的定律

  • Why should the world of the very small, at an atomic level,

    與我們習慣的定律截然不同

  • Why should that world obey the same kind of rules and laws

    是不是非常令人驚訝

  • that we are used to in our world, With apples and oranges

    為何原子層面的超微觀世界

  • And walking around on the street?

    卻同樣遵守著

  • Why would that world behave the same way?

    這個我們習慣的 有蘋果橙子

  • The fluctuating jittery picture of space and time predicted

    還有人在街上走的世界的規則呢

  • By quantum mechanics

    為何那個世界與我們的世界表現相同

  • is in direct conflict With the smooth, orderly,

    這個時間跟空間劇烈動盪

  • Geometric model of space and time

    由量子力學預言的世界

  • described by general relativity.

    與那個平穩的 有條理的

  • But we think that everything,

    廣義相對論描繪的幾何時空模型

  • From the frantic dance of subatomic particles

    格格不入

  • To the majestic swirl of galaxies,

    但我們認為 宇宙萬物

  • Should be explained by just one grand physical principle,

    從亞原子粒子的瘋狂躍動

  • One master equation.

    到星系的瑰麗漩渦

  • If we can find that equation,

    應該由一套普適的物理學定律解釋

  • How the universe really works at every time and place

    由一個主方程描述

  • Will at last be revealed.

    若我們能找出這個方程

  • You see,

    宇宙在何時何地如何運行的奧秘

  • What we need is a theory

    終將揭曉

  • That can cope with the very tiny and the very massive,

    你知道了

  • One that embraces both quantum mechanics and general relativity,

    我們需要的是一套

  • And never breaks down, ever.

    能在微觀和宏觀通用的理論

  • For physicists,

    一套包含了量子力學和廣義相對論

  • Finding a theory that unites general relativity

    永不崩潰的理論

  • And quantum mechanics is the holy grail,

    對物理學家來說

  • Because that framework would give us a single mathematical theory

    這套合併廣義相對論

  • That describes all the forces that rule our universe.

    和量子力學的理論就像聖盃

  • General relativity describes

    因為這套體系能帶來一套數學理論

  • The most familiar of those gravity.

    可以描述所有規範宇宙的作用力

  • The quantum mechanics describes three other forces.

    廣義相對論描述的是

  • The strong nuclear force

    最為熟悉的作用力 重力

  • That's responsible for gluing protons and neutrons together inside of atoms;

    量子力學則描述另外三種作用力

  • Electromagnetism,

    強核力

  • which produces light, Electricity and magnetic attraction;

    能使質子和中子在原子內結合

  • And the nuclear forces.

    電磁力

  • That's the force responsible for radioactive decay.

    能產生光 電 和磁吸引

  • Every event in the universe

    還有核力

  • From the splitting of a atom, to the birth of a star

    能導致輻射衰變

  • Is nothing more than these four forces into acting with manner

    宇宙中的所有現象

  • Albert Einstein spent the last 30 years Of his life

    從原子的分裂 到恆星的誕生

  • searching For a way to describe the forces Of nature

    都不外乎是這幾種力的相互作用

  • in a single theory,

    阿爾伯特·愛因斯坦 用他最後30年

  • And now string theory may fulfill

    尋找能將自然界的所有作用力

  • His dream of unification.

    用單一理論描述的方法

  • For centuries,

    現在 弦理論也許能夠實現

  • Scientists have pictured the fundamental ingredients of nature

    他理論大統一的夢想

  • atoms and the smaller particles inside of them

    幾個世紀以來

  • As tiny balls or points.

    科學家們把自然界的最基本元素

  • But string theory proclaims

    原子和原子內的微觀粒子

  • That at the heart of every bit of matter

    描繪為是小球體 或小點

  • is a tiny, Vibrating strand of energy called a string.

    但弦理論宣告

  • And a new breed of scientist believes

    一切物質的核心

  • These miniscule strings

    都是微小振動的能量物質 叫做弦

  • Are the key to uniting the world of the large

    新一代的科學家相信