Marcus du Sautoy: Symmetry, reality's riddle

131,456 views ・ 2009-10-29

TED


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譯者: Coco Shen 審譯者: Geoff Chen
00:18
On the 30th of May, 1832,
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在1832年5月30日,
00:22
a gunshot was heard
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人們聽到一聲槍響,
00:24
ringing out across the 13th arrondissement in Paris.
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槍聲穿透了巴黎的第十三區
00:27
(Gunshot)
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(槍聲)
00:28
A peasant, who was walking to market that morning,
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一個那天早晨正前往市集的農民
00:31
ran towards where the gunshot had come from,
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朝槍聲傳來的地方跑了過去,
00:33
and found a young man writhing in agony on the floor,
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發現一名年輕男子正痛得在地上打滾,
00:37
clearly shot by a dueling wound.
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顯然他在決鬥中遭到了槍擊。
00:40
The young man's name was Evariste Galois.
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這個年輕人名叫 Evariste • Galois
00:43
He was a well-known revolutionary in Paris at the time.
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是巴黎當時一個有有名的革命者
00:47
Galois was taken to the local hospital
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Galois 被送到了當地的醫院,
00:50
where he died the next day in the arms of his brother.
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第二天死在他兄弟的懷中
00:53
And the last words he said to his brother were,
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他對他兄弟說的臨別遺言是
00:55
"Don't cry for me, Alfred.
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“不要為我哭泣, Alfred
00:57
I need all the courage I can muster
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我需要聚集我能聚集的所有勇氣
00:59
to die at the age of 20."
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讓我在20歲時死去。 ”
01:03
It wasn't, in fact, revolutionary politics
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實際上,革命政治並不是
01:05
for which Galois was famous.
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使 Galois 著名的原因。
01:07
But a few years earlier, while still at school,
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而是幾年前,當他還在上學時,
01:10
he'd actually cracked one of the big mathematical
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他破解了
01:12
problems at the time.
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當時重大數學問題之一
01:14
And he wrote to the academicians in Paris,
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隨後他寫信給巴黎的院士
01:16
trying to explain his theory.
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嘗試解釋他的理論
01:18
But the academicians couldn't understand anything that he wrote.
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但院士們弄不懂他寫的任何東西。
01:21
(Laughter)
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(大笑)
01:22
This is how he wrote most of his mathematics.
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這就是他怎麼寫大部分數學理論的
01:25
So, the night before that duel, he realized
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因此,在決鬥的前一天晚上,他意識到
01:27
this possibly is his last chance
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這可能是他最後一次機會
01:30
to try and explain his great breakthrough.
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來嘗試解釋他的重大突破
01:32
So he stayed up the whole night, writing away,
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所以他徹夜未眠,不停地寫東西,
01:35
trying to explain his ideas.
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試圖解釋他的想法
01:37
And as the dawn came up and he went to meet his destiny,
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隨著黎明的到來,他準備迎接自己的命運。
01:40
he left this pile of papers on the table for the next generation.
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他把桌子上的一堆文件留給了下一代。
01:44
Maybe the fact that he stayed up all night doing mathematics
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也許徹夜研究數學
01:47
was the fact that he was such a bad shot that morning and got killed.
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是他那天早晨受到槍擊且被殺的真正原因
01:50
But contained inside those documents
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但包含在那些文件中的
01:52
was a new language, a language to understand
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是一種新的語言,這種語言能讓人們理解
01:55
one of the most fundamental concepts
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科學的一個最基本的概念,
01:57
of science -- namely symmetry.
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即對稱性。
02:00
Now, symmetry is almost nature's language.
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現今,對稱性幾乎是大自然的語言。
02:02
It helps us to understand so many
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它有助於我們了解許多
02:04
different bits of the scientific world.
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科學世界裡不同的小東西。
02:06
For example, molecular structure.
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例如,分子結構。
02:08
What crystals are possible,
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什麼晶體是能讓
02:10
we can understand through the mathematics of symmetry.
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我們可以通過數學的對稱性來了解的?
02:14
In microbiology you really don't want to get a symmetrical object,
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在微生物學中,你真的不想研究對稱的東西。
02:16
because they are generally rather nasty.
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因為它們一般都比較令人討厭。
02:18
The swine flu virus, at the moment, is a symmetrical object.
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目前的豬流感病毒就是一種結構對稱的病毒。
02:21
And it uses the efficiency of symmetry
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而且它利用對稱的功效
02:23
to be able to propagate itself so well.
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來增強自己繁殖的速度
02:27
But on a larger scale of biology, actually symmetry is very important,
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但從大方向來說,對稱性事實上對生物學非常重要
02:30
because it actually communicates genetic information.
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因為它能傳遞遺傳信息
02:32
I've taken two pictures here and I've made them artificially symmetrical.
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我帶了兩張照片到這兒來,並人工的把他們做成了對稱的
02:36
And if I ask you which of these you find more beautiful,
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如果我問你們覺得哪些更漂亮,
02:39
you're probably drawn to the lower two.
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你們可能會被下面的兩張吸引住。
02:41
Because it is hard to make symmetry.
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因為很難做到對稱,
02:44
And if you can make yourself symmetrical, you're sending out a sign
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所以如果你可以使自己對稱,那麼你在傳遞一種信號
02:46
that you've got good genes, you've got a good upbringing
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它意味著你得到了好的遺傳基因,你有好的教養,
02:49
and therefore you'll make a good mate.
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因而你會有一個好的伴侶。
02:51
So symmetry is a language which can help to communicate
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所以,對稱性是一種語言,它能有助於傳遞
02:54
genetic information.
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遺傳信息。
02:56
Symmetry can also help us to explain
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對稱性還可以幫助我們解釋
02:58
what's happening in the Large Hadron Collider in CERN.
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歐洲粒子物理研究所大型強子對撞機正發生著什麼事情。
03:01
Or what's not happening in the Large Hadron Collider in CERN.
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或者歐洲粒子物理研究所的大型強子對撞機沒有發生什麼事情。
03:04
To be able to make predictions about the fundamental particles
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為了能夠對基本粒子作出預測,
03:06
we might see there,
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我們可能會在那兒看到的(基本粒子),
03:08
it seems that they are all facets of some strange symmetrical shape
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似乎所有的小平面都有某種奇怪的對稱形狀
03:12
in a higher dimensional space.
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當它們在更高維的空間中時。
03:14
And I think Galileo summed up, very nicely,
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我認為伽利略很好地概括了
03:16
the power of mathematics
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數學的力量:
03:18
to understand the scientific world around us.
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它讓我們得以了解周圍的科學世界
03:20
He wrote, "The universe cannot be read
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他寫道:“我們無法閱讀宇宙,
03:22
until we have learnt the language
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除非學會它的語言,
03:24
and become familiar with the characters in which it is written.
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且熟悉其寫作特點。
03:27
It is written in mathematical language,
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它是用數學語言寫的。
03:29
and the letters are triangles, circles and other geometric figures,
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字母是三角形、圓和其他的幾何數字,
03:33
without which means it is humanly impossible
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沒有這些字母就意味著在人力所能及的範圍內是不可能
03:35
to comprehend a single word."
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理解任何一個字。 ”
03:38
But it's not just scientists who are interested in symmetry.
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不只是科學家們對對稱性感興趣。
03:41
Artists too love to play around with symmetry.
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藝術家也喜歡擺弄對稱性。
03:44
They also have a slightly more ambiguous relationship with it.
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他們與對稱性有一些更模糊的關係。
03:47
Here is Thomas Mann talking about symmetry in "The Magic Mountain."
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這是托馬斯•曼在《魔山》中談到的對稱性。
03:50
He has a character describing the snowflake,
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他這樣描寫雪花
03:53
and he says he "shuddered at its perfect precision,
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他說他,“因其有完美的精確度而震撼,
03:56
found it deathly, the very marrow of death."
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發現它死亡的精髓讓他想到死亡。 ”
03:59
But what artists like to do is to set up expectations
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但藝術家們想要做的是樹立對對稱性的期望,
04:01
of symmetry and then break them.
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然後打破它們。
04:03
And a beautiful example of this
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就這一點我找到了一個很好的例子,
04:05
I found, actually, when I visited a colleague of mine
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其實是當我拜訪我的同事
04:07
in Japan, Professor Kurokawa.
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在日本的黑川紀章教授時發現的
04:09
And he took me up to the temples in Nikko.
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他帶我到日光市的寺廟去
04:12
And just after this photo was taken we walked up the stairs.
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就在拍好這張照片後,我們走上樓梯,
04:15
And the gateway you see behind
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你們看到的這後面的大門
04:17
has eight columns, with beautiful symmetrical designs on them.
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有八根柱子,都有著漂亮的對稱性設計。
04:20
Seven of them are exactly the same,
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其中七個是完全一樣的,
04:22
and the eighth one is turned upside down.
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而第八個是顛倒過來的。
04:25
And I said to Professor Kurokawa,
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我就對黑川紀章教授說:
04:27
"Wow, the architects must have really been kicking themselves
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“哇,建築師們肯定自責的很
04:29
when they realized that they'd made a mistake and put this one upside down."
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要是他麼發現犯了這麼一個錯誤,這根柱子竟然是相反的。 ”
04:32
And he said, "No, no, no. It was a very deliberate act."
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他說,“不,不,不。這是故意設計成這樣的。”
04:35
And he referred me to this lovely quote from the Japanese
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他還向我提到了這個可愛的出處,來自日本
04:37
"Essays in Idleness" from the 14th century,
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1 4世紀的《徒然草》
04:40
in which the essayist wrote, "In everything,
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其中,散文家寫道:“在一切事物中,
04:42
uniformity is undesirable.
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一致性是不可取的。
04:45
Leaving something incomplete makes it interesting,
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留下一些不完整的東西會更有趣,
04:47
and gives one the feeling that there is room for growth."
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而且一致性給人一種沒有發展空間的感覺。 ”
04:50
Even when building the Imperial Palace,
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即使是建造皇宮時,
04:52
they always leave one place unfinished.
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他們也總是留下一個未完工的地方。
04:56
But if I had to choose one building in the world
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但如果我必須選擇這世界上的一個建築,
04:59
to be cast out on a desert island, to live the rest of my life,
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將其扔到一個荒島上,且我要在那裡度過餘生,
05:02
being an addict of symmetry, I would probably choose the Alhambra in Granada.
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作為一個對對稱性痴迷的人,我可能會選擇在格拉納達的阿爾罕布拉。
05:06
This is a palace celebrating symmetry.
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這是一座歌頌對稱性的宮殿。
05:08
Recently I took my family --
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最近,我帶我的家人——
05:10
we do these rather kind of nerdy mathematical trips, which my family love.
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我們進行這種並沒有學術氣息的數學旅行,我的家人都很喜歡。
05:13
This is my son Tamer. You can see
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這是我的兒子塔梅爾。你們可以看到
05:15
he's really enjoying our mathematical trip to the Alhambra.
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他真的很喜歡我們在阿爾罕布拉的數學之旅。
05:18
But I wanted to try and enrich him.
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但我想嘗試使他變得充實。
05:21
I think one of the problems about school mathematics
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我認為學校教的數學存在的一個問題就是
05:23
is it doesn't look at how mathematics is embedded
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它沒有關注數學是如何被運用於
05:25
in the world we live in.
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我們所處的這個世界。
05:27
So, I wanted to open his eyes up to
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所以,我想開拓他的眼界,讓他知道
05:29
how much symmetry is running through the Alhambra.
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阿爾罕布拉運用著多少對稱性。
05:32
You see it already. Immediately you go in,
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你們已經看到了。你一走進去,
05:34
the reflective symmetry in the water.
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水中有反映出對稱。
05:36
But it's on the walls where all the exciting things are happening.
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但是,所有令人興奮的事情發生在牆壁上。
05:39
The Moorish artists were denied the possibility
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人們否認摩爾藝術家能夠
05:41
to draw things with souls.
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用靈魂來繪畫。
05:43
So they explored a more geometric art.
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因此,他們探索出一種更加幾何化的藝術。
05:45
And so what is symmetry?
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那麼什麼是對稱性?
05:47
The Alhambra somehow asks all of these questions.
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阿爾罕布拉以某種方式提出了所有這些問題。
05:50
What is symmetry? When [there] are two of these walls,
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什麼是對稱性?當[那兒]有兩面牆時,
05:52
do they have the same symmetries?
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他們有相同的對稱性嗎?
05:54
Can we say whether they discovered
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我們可以說他們是否發現了
05:56
all of the symmetries in the Alhambra?
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阿爾罕布拉所有的對稱性嗎?
05:59
And it was Galois who produced a language
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是 Galois 研製出了一種語言
06:01
to be able to answer some of these questions.
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來回答這樣的問題
06:04
For Galois, symmetry -- unlike for Thomas Mann,
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對 Galois 來說,對稱性不是托馬斯曼所說的
06:07
which was something still and deathly --
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靜態的和死一般的東西
06:09
for Galois, symmetry was all about motion.
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對 Galois 來說,所有的對稱性都是關於運動的
06:12
What can you do to a symmetrical object,
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你能對一個對稱性的物體做些什麼?
06:14
move it in some way, so it looks the same
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用某種方法移動它,讓它看起來
06:16
as before you moved it?
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跟你移動它之前一樣?
06:18
I like to describe it as the magic trick moves.
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我喜歡把這形容為神奇的假動作。
06:20
What can you do to something? You close your eyes.
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你對一些東西可以做些什麼?閉上你的眼睛。
06:22
I do something, put it back down again.
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我移動它,再把它放回到原處。
06:24
It looks like it did before it started.
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它看起來和動之前一樣。
06:26
So, for example, the walls in the Alhambra --
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那麼,例如,阿爾罕布拉的牆壁。
06:28
I can take all of these tiles, and fix them at the yellow place,
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我可以把所有的這些瓦片拿起來,把他們放在這個黃色的地方,
06:32
rotate them by 90 degrees,
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並把它們旋轉九十度,
06:34
put them all back down again and they fit perfectly down there.
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再把他們都放回去,它們非常吻合。
06:37
And if you open your eyes again, you wouldn't know that they'd moved.
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如果你再睜開你的眼睛,你不會知道它們被移動過。
06:40
But it's the motion that really characterizes the symmetry
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但正是運動才使對稱性
06:43
inside the Alhambra.
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在阿爾罕布拉具有特色。
06:45
But it's also about producing a language to describe this.
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但也要創造一種語言來描繪它。
06:47
And the power of mathematics is often
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數學的力量往往
06:50
to change one thing into another, to change geometry into language.
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把一樣東西變成另一樣,把幾何變成語言。
06:54
So I'm going to take you through, perhaps push you a little bit mathematically --
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因此,我將帶你經歷,可能強加一些數學的東西給你們,
06:57
so brace yourselves --
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所以撐住自己,
06:59
push you a little bit to understand how this language works,
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強加一些數學的知識讓你們了解這種語言是怎麼運作的,
07:02
which enables us to capture what is symmetry.
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這讓我們能夠捕捉到什麼是對稱性。
07:04
So, let's take these two symmetrical objects here.
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那讓我們把這兩個對稱物放到這兒。
07:07
Let's take the twisted six-pointed starfish.
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拿這個扭曲了的六角海星來說。
07:09
What can I do to the starfish which makes it look the same?
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我怎麼做能讓這個海星看起來和原來一樣呢?
07:12
Well, there I rotated it by a sixth of a turn,
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嗯,我把它旋轉了六分之一圈,
07:15
and still it looks like it did before I started.
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它看起來仍然跟我動過之前一樣。
07:17
I could rotate it by a third of a turn,
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我可以把它旋轉三分之一圈,
07:20
or a half a turn,
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或者半圈,
07:22
or put it back down on its image, or two thirds of a turn.
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或將它恢復到原圖,或旋轉三分之二圈。
07:25
And a fifth symmetry, I can rotate it by five sixths of a turn.
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第五種對稱,我可以把它旋轉六分之五圈。
07:29
And those are things that I can do to the symmetrical object
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這些就是我能對對稱物所做的,
07:32
that make it look like it did before I started.
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可以讓它看起來跟我動它們之前一樣。
07:35
Now, for Galois, there was actually a sixth symmetry.
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對 Galois 來說,實際上還有第六種對稱。
07:38
Can anybody think what else I could do to this
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大家能想到其它什麼辦法
07:40
which would leave it like I did before I started?
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可以讓它跟我動它之前一樣?
07:43
I can't flip it because I've put a little twist on it, haven't I?
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我不能翻轉它,因為我已​​經把它扭曲了一些,是吧?
07:46
It's got no reflective symmetry.
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這樣它沒有反射對稱了。
07:48
But what I could do is just leave it where it is,
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但我可以做的就是把它放在原處,
07:51
pick it up, and put it down again.
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把它拿起來再把它放下。
07:53
And for Galois this was like the zeroth symmetry.
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對 Galois 來說,這就像是第零個對稱。
07:56
Actually, the invention of the number zero
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其實,數字零的發明
07:59
was a very modern concept, seventh century A.D., by the Indians.
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是一個非常現代化的概念,它是公元七世紀印度人發明的。
08:02
It seems mad to talk about nothing.
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談論無有感覺很瘋狂。
08:05
And this is the same idea. This is a symmetrical --
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這是同樣的概念。這是對稱的——
08:07
so everything has symmetry, where you just leave it where it is.
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所以一切事物都有對稱性,把它放在拿起它的地方。
08:09
So, this object has six symmetries.
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所以這個物體有六種對稱。
08:12
And what about the triangle?
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那三角形呢?
08:14
Well, I can rotate by a third of a turn clockwise
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嗯,我可以把它順時針旋轉三分之一圈
08:18
or a third of a turn anticlockwise.
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或逆時針旋轉三分之一圈。
08:20
But now this has some reflectional symmetry.
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但現在有反射對稱
08:22
I can reflect it in the line through X,
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我可以在X軸上翻轉它,
08:24
or the line through Y,
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或在Y軸上,
08:26
or the line through Z.
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或在Z軸上。
08:28
Five symmetries and then of course the zeroth symmetry
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五種對稱,當然還有第零個對稱,
08:31
where I just pick it up and leave it where it is.
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我把它拿起來,放回原處。
08:34
So both of these objects have six symmetries.
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因此,這些物體都有六種對稱。
08:37
Now, I'm a great believer that mathematics is not a spectator sport,
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現在,我十分相信數學不是旁觀者的運動,
08:40
and you have to do some mathematics
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你必須做一些數學運算
08:42
in order to really understand it.
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才能真正理解它。
08:44
So here is a little question for you.
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這兒有個小問題問問你們。
08:46
And I'm going to give a prize at the end of my talk
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我將在講座結束後給一個獎品
08:48
for the person who gets closest to the answer.
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給那個給出的答案最接近的人。
08:50
The Rubik's Cube.
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魔術方塊
08:52
How many symmetries does a Rubik's Cube have?
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一個魔術方塊有多少種對稱?
08:55
How many things can I do to this object
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有多少種方法可以在動了這個物體,
08:57
and put it down so it still looks like a cube?
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且把它放下後它仍然看起來像一個立方體?
08:59
Okay? So I want you to think about that problem as we go on,
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好嗎?我希望隨著講座的繼續,你們可以想想這個問題,
09:02
and count how many symmetries there are.
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數數它有多少種對稱。
09:04
And there will be a prize for the person who gets closest at the end.
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講座結束後獎品會給答案最接近的人
09:08
But let's go back down to symmetries that I got for these two objects.
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讓我們回到這兩個物體的對稱性上。
09:12
What Galois realized: it isn't just the individual symmetries,
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Galois 意識到這不僅僅是個體的對稱性,
09:15
but how they interact with each other
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而是個體之間如何相互作用
09:17
which really characterizes the symmetry of an object.
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才真正賦予了一個物體具有對稱性的特點。
09:21
If I do one magic trick move followed by another,
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如果我做一個神奇的假動作,然後再做一個,
09:24
the combination is a third magic trick move.
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兩個合併起來就是第三個神奇的假動作。
09:26
And here we see Galois starting to develop
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這裡我們了解到 Glaois 開始開發
09:28
a language to see the substance
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一種語言來研究
09:31
of the things unseen, the sort of abstract idea
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看不見的東西所具有的內在含義,以及
09:33
of the symmetry underlying this physical object.
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物理物體中存在的對稱性的抽象的概念。
09:36
For example, what if I turn the starfish
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例如,如果我把海星旋轉
09:39
by a sixth of a turn,
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六分之一圈,
09:41
and then a third of a turn?
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然後再轉三分之一圈會,結果會怎樣?
09:43
So I've given names. The capital letters, A, B, C, D, E, F,
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所以我給它們取了名字。大寫的字母A、B、C、D、E、F,
09:46
are the names for the rotations.
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這些名字旋轉的代號。
09:48
B, for example, rotates the little yellow dot
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例如B,旋轉小黃點,
09:51
to the B on the starfish. And so on.
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它位於海星上的B處,諸如此類。
09:54
So what if I do B, which is a sixth of a turn,
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那麼,如果我旋轉B,轉六分之一圈,
09:56
followed by C, which is a third of a turn?
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其次是C,轉三分之一圈?
09:59
Well let's do that. A sixth of a turn,
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嗯,讓我們開始。六分之一圈,
10:01
followed by a third of a turn,
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接著是三分之一圈,
10:03
the combined effect is as if I had just rotated it by half a turn in one go.
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合併後的效果就像我剛剛把它一次旋轉了半圈一樣。
10:08
So the little table here records
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那這個小表格記載著
10:10
how the algebra of these symmetries work.
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這些對稱的代數是怎麼運作的。
10:13
I do one followed by another, the answer is
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我將一個接一個的旋轉,結果就是
10:15
it's rotation D, half a turn.
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D旋轉了半圈。
10:17
What I if I did it in the other order? Would it make any difference?
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如果我按其他順序旋轉呢?會有什麼不同嗎?
10:20
Let's see. Let's do the third of the turn first, and then the sixth of a turn.
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讓我們來看看。讓我們先旋轉三分之一圈,然後旋轉六分之一圈。
10:24
Of course, it doesn't make any difference.
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當然,沒有什麼差別。
10:26
It still ends up at half a turn.
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結果仍然是半圈。
10:28
And there is some symmetry here in the way the symmetries interact with each other.
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某種對稱方式是通過相互作用得到的。
10:33
But this is completely different to the symmetries of the triangle.
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但這與三角形的對稱性是完全不同的。
10:36
Let's see what happens if we do two symmetries
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讓我們看看如果對三角形
10:38
with the triangle, one after the other.
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一個接一個的進行兩個對稱旋轉會怎樣。
10:40
Let's do a rotation by a third of a turn anticlockwise,
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讓我們逆時針旋轉三分之一圈,
10:43
and reflect in the line through X.
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然後在X軸上翻轉。
10:45
Well, the combined effect is as if I had just done the reflection in the line through Z
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嗯,合併後的效果就像我剛剛以Z軸翻轉
10:49
to start with.
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開始一樣。
10:51
Now, let's do it in a different order.
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現在,讓我們按不同的順序來一次。
10:53
Let's do the reflection in X first,
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我們先在X軸上翻轉,
10:55
followed by the rotation by a third of a turn anticlockwise.
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然後逆時針旋轉三分之一圈。
10:59
The combined effect, the triangle ends up somewhere completely different.
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合併後的效果是三角形停的地方完全不同。
11:02
It's as if it was reflected in the line through Y.
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就像是在Y軸上翻轉了一樣。
11:05
Now it matters what order you do the operations in.
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現在看來這與你操作它的順序有關。
11:08
And this enables us to distinguish
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這使我們能夠區分
11:10
why the symmetries of these objects --
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為什麼這些物體的對稱性
11:12
they both have six symmetries. So why shouldn't we say
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都有六個。那麼,為什麼我們不能說
11:14
they have the same symmetries?
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它們有相同的對稱性呢?
11:16
But the way the symmetries interact
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但對稱相互作用的方式
11:18
enable us -- we've now got a language
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使我們——我們現在已經有一種語言
11:20
to distinguish why these symmetries are fundamentally different.
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來區分為什麼這些對稱在根本上是不同的。
11:23
And you can try this when you go down to the pub, later on.
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你也可以嘗試一下,當你去酒吧時,以後去的時候。
11:26
Take a beer mat and rotate it by a quarter of a turn,
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拿一個啤酒墊,把它旋轉四分之一圈,
11:29
then flip it. And then do it in the other order,
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然後翻轉它。然後再按其它順序做,
11:31
and the picture will be facing in the opposite direction.
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酒墊上的圖將是朝反方向面對你的。
11:35
Now, Galois produced some laws for how these tables -- how symmetries interact.
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Galois 為這些表格以及對稱性如何相互作用研究出了一些定律。
11:39
It's almost like little Sudoku tables.
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這像一個小數獨表。
11:41
You don't see any symmetry twice
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你看不到任何重複的對稱
11:43
in any row or column.
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出現在任何一欄或一行中。
11:45
And, using those rules, he was able to say
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通過運用那些定律,他可以說
11:49
that there are in fact only two objects
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事實上只有兩個物體
11:51
with six symmetries.
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有六個對稱。
11:53
And they'll be the same as the symmetries of the triangle,
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而且這六個對稱將和三角形的對稱,
11:56
or the symmetries of the six-pointed starfish.
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或六角海星的對稱是一樣的。
11:58
I think this is an amazing development.
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我覺得這是一個驚人的發展。
12:00
It's almost like the concept of number being developed for symmetry.
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它幾乎是為了對稱而研製的數的概念。
12:04
In the front here, I've got one, two, three people
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在這前面,我請一、二、三個人
12:06
sitting on one, two, three chairs.
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坐在一、二、三把椅子上。
12:08
The people and the chairs are very different,
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坐在椅子上的人都不一樣,
12:11
but the number, the abstract idea of the number, is the same.
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但是數字,數字的抽象的觀念,都是一樣的。
12:14
And we can see this now: we go back to the walls in the Alhambra.
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現在我們可以看到這個:我們回到阿爾罕布拉的牆壁。
12:17
Here are two very different walls,
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這有兩面很不一樣的牆壁,
12:19
very different geometric pictures.
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很不相同的幾何圖片。
12:21
But, using the language of Galois,
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但是,利用 Galois 的語言
12:23
we can understand that the underlying abstract symmetries of these things
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我們可以知道這些東西含有的抽象的對稱
12:26
are actually the same.
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實際上是相同的。
12:28
For example, let's take this beautiful wall
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例如,讓我們把這面漂亮的牆
12:30
with the triangles with a little twist on them.
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和三角形稍微扭曲一下。
12:33
You can rotate them by a sixth of a turn
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你可以把它們旋轉六分之一圈,
12:35
if you ignore the colors. We're not matching up the colors.
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如果忽略他們的顏色。我們不是在做顏色配對
12:37
But the shapes match up if I rotate by a sixth of a turn
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而是在形狀配對,如果我把他們旋轉六分之一圈,
12:40
around the point where all the triangles meet.
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圍繞著所有三角形交彙的一點旋轉。
12:43
What about the center of a triangle? I can rotate
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三角形的中心會怎麼樣?我可以
12:45
by a third of a turn around the center of the triangle,
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圍繞著三角形的中心把他們旋轉三分之一圈,
12:47
and everything matches up.
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那麼一切就都對上了。
12:49
And then there is an interesting place halfway along an edge,
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這兒有個有趣的地方,沿著邊的一半
12:51
where I can rotate by 180 degrees.
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我可以把它旋轉180度。
12:53
And all the tiles match up again.
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那麼所有的瓦片又重新匹配了。
12:56
So rotate along halfway along the edge, and they all match up.
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所以,沿著邊的一半旋轉,那麼他們都能配合上。
12:59
Now, let's move to the very different-looking wall in the Alhambra.
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現在,讓我們移動阿爾罕布拉的一面外觀非常不一樣的牆。
13:03
And we find the same symmetries here, and the same interaction.
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我們在這兒發現同樣的對稱性和同樣的相互作用。
13:06
So, there was a sixth of a turn. A third of a turn where the Z pieces meet.
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那麼是轉了六分之一轉。轉了三分之一圈時第Z片交會
13:11
And the half a turn is halfway between the six pointed stars.
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旋轉半圈時離六角星交會還有一半。
13:15
And although these walls look very different,
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儘管這些牆壁看起來非常不同,
13:17
Galois has produced a language to say
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Galois 研製出一種語言說,
13:20
that in fact the symmetries underlying these are exactly the same.
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其實這些東西所具有的對稱性是完全相同的。
13:23
And it's a symmetry we call 6-3-2.
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這個對稱性我們稱之為6-3-2。
13:26
Here is another example in the Alhambra.
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另一個阿爾罕布拉的例子。
13:28
This is a wall, a ceiling, and a floor.
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這是一面牆、天花板和地板。
13:31
They all look very different. But this language allows us to say
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它們都看起來都非常不一樣。但是,這種語言讓我們可以說
13:34
that they are representations of the same symmetrical abstract object,
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它們是相同的對稱的抽象物體,
13:38
which we call 4-4-2. Nothing to do with football,
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我們稱之為4-4-2。這與足球毫無關係,
13:40
but because of the fact that there are two places where you can rotate
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而是因為他們都有兩個你可以旋轉
13:43
by a quarter of a turn, and one by half a turn.
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四分之一圈和二分之一圈的地方。
13:47
Now, this power of the language is even more,
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現在,這種語言的力量更加強大,
13:49
because Galois can say,
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因為 Galois 可能會說,
13:51
"Did the Moorish artists discover all of the possible symmetries
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“摩爾藝術家發現了阿爾罕布拉牆上所有可能對稱的
13:54
on the walls in the Alhambra?"
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地方了嗎? ”
13:56
And it turns out they almost did.
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結果是他們幾乎都發現了。
13:58
You can prove, using Galois' language,
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你可以用伽羅瓦的語言來證明,
14:00
there are actually only 17
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實際上只有17種
14:02
different symmetries that you can do in the walls in the Alhambra.
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可以在阿爾罕布拉的牆上得到的不同的對稱。
14:06
And they, if you try to produce a different wall with this 18th one,
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而且他們,如果你嘗試研製出第18面不同的牆壁,
14:09
it will have to have the same symmetries as one of these 17.
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這面牆肯定與17種對稱中的一種對稱是相同的。
14:14
But these are things that we can see.
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但這些都是我們可以看到的。
14:16
And the power of Galois' mathematical language
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而 Galois 的數學語言的力量
14:18
is it also allows us to create
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也讓我們能
14:20
symmetrical objects in the unseen world,
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在看不見的世界裡創造對稱的物體,
14:23
beyond the two-dimensional, three-dimensional,
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超越二維、三維,
14:25
all the way through to the four- or five- or infinite-dimensional space.
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全都向四維或五維或無窮維空間發展。
14:28
And that's where I work. I create
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而這正是我在研究的東西。我創建
14:30
mathematical objects, symmetrical objects,
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數學對象和對稱物體,
14:32
using Galois' language,
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通過運用 Galois 的語言
14:34
in very high dimensional spaces.
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在非常高維的空間裡創建。
14:36
So I think it's a great example of things unseen,
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因此,我認為這是個對於看不見的東西的很好的例子,
14:38
which the power of mathematical language allows you to create.
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數學語言的力量讓你可以創建出來。
14:42
So, like Galois, I stayed up all last night
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因此,像 Glaois 一樣,我昨晚徹夜未眠
14:44
creating a new mathematical symmetrical object for you,
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為你們建立了一個新的數學對稱物。
14:48
and I've got a picture of it here.
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我這兒有一張它的照片。
14:50
Well, unfortunately it isn't really a picture. If I could have my board
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但是,可惜的是它不是一張真正的照片。我可以把我的圖板
14:53
at the side here, great, excellent.
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放在這邊嗎?很好,非常好。
14:55
Here we are. Unfortunately, I can't show you
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這兒。可惜的是我無法向你們展示
14:57
a picture of this symmetrical object.
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這個對稱物的照片。
14:59
But here is the language which describes
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但這兒有語言能描繪
15:02
how the symmetries interact.
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其對稱性怎麼相互作用的。
15:04
Now, this new symmetrical object
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現在這個新的對稱物
15:06
does not have a name yet.
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還沒有名字。
15:08
Now, people like getting their names on things,
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就像人們給東西命名一樣,
15:10
on craters on the moon
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給月球上的隕石坑命名,
15:12
or new species of animals.
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或給新動物品種命名一樣。
15:14
So I'm going to give you the chance to get your name on a new symmetrical object
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所以我想給你們機會來給新的對稱物命名,
15:18
which hasn't been named before.
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以前沒有給它取過名字。
15:20
And this thing -- species die away,
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而且這個東西——物種會逐漸消失,
15:22
and moons kind of get hit by meteors and explode --
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月球可能會被隕石撞擊並發生爆炸——
15:25
but this mathematical object will live forever.
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但是這個數學物體將長存於世。
15:27
It will make you immortal.
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它將使你不朽。
15:29
In order to win this symmetrical object,
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為了贏得這個對稱物,
15:32
what you have to do is to answer the question I asked you at the beginning.
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你所要做的就是回答我在一開始問的問題。
15:35
How many symmetries does a Rubik's Cube have?
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魔術方塊有多少種對稱呢?
15:39
Okay, I'm going to sort you out.
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好吧,我來給你們整理一下。
15:41
Rather than you all shouting out, I want you to count how many digits there are
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而不是大家都喊出來,我想讓你們數數有多少位數字
15:44
in that number. Okay?
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在那個答案裡。好嗎?
15:46
If you've got it as a factorial, you've got to expand the factorials.
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如果你得出的結果是一個階乘,那麼你要擴大它的階乘。
15:49
Okay, now if you want to play,
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好了,現在如果你想參與,
15:51
I want you to stand up, okay?
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我希望你能站起來,好嗎?
15:53
If you think you've got an estimate for how many digits,
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如果你認為你已經估計出了它有多少位數字,
15:55
right -- we've already got one competitor here.
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好的——我們在這兒已經有了一位參賽者——
15:58
If you all stay down he wins it automatically.
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如果你們都繼續坐著,那麼他就自動贏了。
16:00
Okay. Excellent. So we've got four here, five, six.
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好的。很好。我們已經有四位、五位、六位。
16:03
Great. Excellent. That should get us going. All right.
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很好。太好了。讓我們繼續。好了。
16:08
Anybody with five or less digits, you've got to sit down,
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你們中有人的答案是等於或少於五位數的,那你得坐下了。
16:11
because you've underestimated.
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因為你們估計少了。
16:13
Five or less digits. So, if you're in the tens of thousands you've got to sit down.
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五位數或更少的。那麼,如果你的答案是幾萬的話,你得坐下。
16:17
60 digits or more, you've got to sit down.
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六十或六十多位數的,你必須坐下。
16:20
You've overestimated.
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你估計得多了。
16:22
20 digits or less, sit down.
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二十位數或二十位以下的,坐下。
16:26
How many digits are there in your number?
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你的答案是幾位數?
16:31
Two? So you should have sat down earlier.
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兩個?那你早就該坐下了。
16:33
(Laughter)
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(大笑)
16:34
Let's have the other ones, who sat down during the 20, up again. Okay?
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讓我們再來問問其他人,誰估計的是二十位的,請再次站起來,好嗎?
16:38
If I told you 20 or less, stand up.
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如果我告訴你是二十位或二十位以下,請站起來。
16:40
Because this one. I think there were a few here.
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因為這一個。我想應該有一些人。
16:42
The people who just last sat down.
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誰是最後一個坐下去的。
16:45
Okay, how many digits do you have in your number?
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好的,你的答案是多少位數?
16:50
(Laughs)
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(笑)
16:53
21. Okay good. How many do you have in yours?
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21。好的,很好。你的是多少位?
16:55
18. So it goes to this lady here.
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18。那麼是這位女士贏了。
16:58
21 is the closest.
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21是最接近的。
17:00
It actually has -- the number of symmetries in the Rubik's cube
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實際上,魔術方塊對稱種數的答案
17:02
has 25 digits.
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有25位數字。
17:04
So now I need to name this object.
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那麼現在我需要給這個物體命名。
17:06
So, what is your name?
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嗯,你叫什麼名字?
17:08
I need your surname. Symmetrical objects generally --
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我需要你的姓氏。對稱的物體一般——
17:11
spell it for me.
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為我拼寫一下。
17:13
G-H-E-Z
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G-H-E-Z
17:20
No, SO2 has already been used, actually,
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不,SO2已經用過了,其實,
17:22
in the mathematical language. So you can't have that one.
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在數學語言裡。你不能用那個名字。
17:24
So Ghez, there we go. That's your new symmetrical object.
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Ghez,就是這個名字啦。這是你的新的對稱物。
17:26
You are now immortal.
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你現在是不朽的了。
17:28
(Applause)
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(鼓掌)
17:34
And if you'd like your own symmetrical object,
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而且,如果你想用你自己的對稱物,
17:36
I have a project raising money for a charity in Guatemala,
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我有一個項目,是為在瓜地馬拉的慈善籌錢的,
17:39
where I will stay up all night and devise an object for you,
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我可以熬夜為你發明一個物體,
17:42
for a donation to this charity to help kids get into education in Guatemala.
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讓你可以為慈善捐款來幫助瓜地馬拉的孩子們,讓他們能接受教育。
17:46
And I think what drives me, as a mathematician,
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我認為,作為一個數學家,
17:49
are those things which are not seen, the things that we haven't discovered.
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給我動力的是那些看不到的東西,是我們還未發現的東西。
17:53
It's all the unanswered questions which make mathematics a living subject.
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它們都是懸而未決的問題,這使數學繼續活著
17:57
And I will always come back to this quote from the Japanese "Essays in Idleness":
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我常常想起引自日本《徒然草》中的這句話:
18:00
"In everything, uniformity is undesirable.
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“在一切事物中,一致性是不可取的。
18:03
Leaving something incomplete makes it interesting,
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留下若干不完整,會更有趣,
18:06
and gives one the feeling that there is room for growth." Thank you.
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並給予一種仍有發展空間的感覺。 ”謝謝。
18:09
(Applause)
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(掌聲)
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