ABOUT THE SPEAKER
Scott Rickard - Mathematician
Scott Rickard is passionate about mathematics, music -- and educating the next generation of scientists and mathematicians.

Why you should listen

Scott Rickard is a professor at University College Dublin. His interest in both music and math led him to try and solve an interesting math problem: a musical score with no pattern. He has degrees in Mathematics, Computer Science, and Electrical Engineering from MIT, and MA and PhD degrees in Applied and Computational Mathematics from Princeton.

At University College Dublin, he founded the Complex & Adaptive Systems Laboratory, where biologists, geologists, mathematicians, computer scientists, social scientists and economists work on problems that matter to people. He is also the founder of ScienceWithMe!, an online community dedicated to engaging youth through science and math.

More profile about the speaker
Scott Rickard | Speaker | TED.com
TEDxMIA

Scott Rickard: The beautiful math behind the world's ugliest music

Scott Rickard: The beautiful math behind the ugliest music

Filmed:
4,270,382 views

Scott Rickard set out to engineer the ugliest possible piece of music, devoid of repetition, using a mathematical concept known as the Costas Array. In this talk, he shares the math behind musical beauty (and its opposite). (Filmed at TEDxMIA.)
- Mathematician
Scott Rickard is passionate about mathematics, music -- and educating the next generation of scientists and mathematicians. Full bio

Double-click the English transcript below to play the video.

00:10
So what makes品牌 a piece of music音乐 beautiful美丽?
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是什么让一段音乐动听?
00:13
Well, most musicologists音乐学家 would argue争论
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大部分音乐理论家会争论说,
重复性是让音乐动听的关键,
00:15
that repetition重复 is a key aspect方面 of beauty美女,
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当我们脑海中冒出的一段旋律,
一个主题或是一个音乐的构思时,
00:18
the idea理念 that we take a melody旋律,
a motif主题, a musical音乐 idea理念,
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我们重复它,产生一种对重复的期待,
00:21
we repeat重复 it, we set up
the expectation期望 for repetition重复,
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然后我们要么实现它,要么打破重复。
00:24
and then we either realize实现 it
or we break打破 the repetition重复.
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那就是动听的关键部分。
00:27
And that's a key component零件 of beauty美女.
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因此,如果循环往复
是使其动听的关键,
00:29
So if repetition重复 and patterns模式
are key to beauty美女,
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00:33
then what would the absence缺席
of patterns模式 sound声音 like,
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那么如果我们写下一段
没有任何重复的音乐,
00:35
if we wrote a piece of music音乐
that had no repetition重复 whatsoever任何 in it?
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除去这种模式的音乐
听起来会是怎样的呢?
00:40
That's actually其实 an interesting有趣
mathematical数学的 question.
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那实际上是一个有趣的数学问题。
有没有可能写出一段
没有任何重复旋律的音乐呢?
00:43
Is it possible可能 to write a piece of music音乐
that has no repetition重复 whatsoever任何?
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当然不是随机的旋律——
随机很容易做到。
00:47
It's not random随机 -- random随机 is easy简单.
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00:48
Repetition-free无重复性, it turns
out, is extremely非常 difficult,
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没有重复, 其实是极为困难的。
并且实际上我们能
实现它的唯一原因
00:51
and the only reason原因
that we can actually其实 do it
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00:53
is because of a man
who was hunting狩猎 for submarines潜艇.
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是因为曾经有一个
研发潜水艇的男人。
00:57
It turns out, a guy who was trying
to develop发展 the world's世界 perfect完善 sonar声纳 ping
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他试图开发出世界上
完美的声波定位脉冲,
这解决了如何写出没有
重复的音乐的难题。
01:01
solved解决了 the problem问题 of writing写作
pattern-free无模式 music音乐.
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那就是我们今天要谈论的主题。
01:04
And that's what the topic话题
of the talk is today今天.
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01:10
So, recall召回 that in sonar声纳,
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说到声呐,
你有一艘在水中发出声音的船,
01:12
you have a ship that sends发送
out some sound声音 in the water,
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01:15
and it listens监听 for it -- an echo回声.
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然后等待回声。
那个声音向下发射,发出回声,
再向下,发出回声。
01:17
The sound声音 goes down, it echoes回声
back, it goes down, echoes回声 back.
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声音往返的时间将告诉
你距离目标有多远:
01:20
The time it takes the sound声音 to come back
tells告诉 you how far away it is:
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如果回声是高音,
01:24
if it comes at a higher更高 pitch沥青,
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这是因为它正向你驶来;
01:25
it's because the thing
is moving移动 toward you;
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如果回声是低音,那么它正驶离你。
01:27
if it comes back at a lower降低 pitch沥青,
it's moving移动 away from you.
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那么你将如何设计一个
完美的声纳定位脉冲呢?
01:30
So how would you design设计
a perfect完善 sonar声纳 ping?
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01:32
Well, in the 1960s, a guy
by the name名称 of John约翰 Costas科斯塔斯
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在20世纪60年代,一位
名叫约翰 · 科斯塔斯男人
曾致力于为海军研发极其
昂贵的声纳定位系统。
01:36
was working加工 on the Navy's海军 extremely非常
expensive昂贵 sonar声纳 system系统.
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但并没有成功,因为他们
所使用的脉冲并不合适。
01:40
It wasn't working加工, because the ping
they were using运用 was inappropriate不当.
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就像是这一系列的脉冲。
01:43
It was a ping much
like the following以下 here.
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你可以把它想作音符和时间。
01:46
You can think of this as the notes笔记
and this is time.
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01:50
(Piano钢琴 notes笔记 play high to low)
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(钢琴音符从高到低地弹奏)
因此那就是他们正使用的声纳
定位脉冲,一个向下的啁啾声。
01:52
So that was the sonar声纳 ping
they were using运用, a down chirp叽叽喳喳.
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结果证明那是非常不好的脉冲。
01:55
It turns out that's a really bad ping.
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01:57
Why? Because it looks容貌
like shifts转变 of itself本身.
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为什么?因为它看起来
像是一个接一个的位移。
前两个音符之间的
关系和后两个相同,
02:00
The relationship关系 between之间 the first
two notes笔记 is the same相同 as the second第二 two,
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然后以此类推。
02:04
and so forth向前.
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02:05
So he designed设计 a different不同
kind of sonar声纳 ping,
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因此他设计了一种
不同的声纳定位脉冲,
一种看起来随机的。
02:08
one that looks容貌 random随机.
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这些看起来是一组随机
模式的点,但它们不是。
02:09
These look like a random随机 pattern模式
of dots, but they're not.
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如果你非常仔细地观察,
02:12
If you look very carefully小心,
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你可能会发现,实际上
每对点之间的关系
02:13
you may可能 notice注意 that, in fact事实,
the relationship关系 between之间 each pair of dots
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是有区别的。
02:17
is distinct不同.
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没有任何一对是重复的。
02:18
Nothing is ever repeated重复.
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前两个音符和其他每对音符
02:20
The first two notes笔记
and every一切 other pair of notes笔记
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有着不同的关系。
02:23
have a different不同 relationship关系.
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02:26
So the fact事实 that we know
about these patterns模式 is unusual异常.
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因此我们知道了
这些模式是与众不同的。
约翰 · 科斯塔斯便是
这些模式的发明者。
02:29
John约翰 Costas科斯塔斯 is the inventor发明者
of these patterns模式.
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这是2006年的一张照片,
他不久后就去世了。
02:31
This is a picture图片 from 2006,
shortly不久 before his death死亡.
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他是一位效力于海军的
声纳定位工程师。
02:34
He was the sonar声纳 engineer工程师
working加工 for the Navy海军.
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他思考着这些模式,
02:37
He was thinking思维 about these patterns模式,
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同时他徒手画出了12号尺寸的图——
02:39
and he was, by hand, able能够 to come
up with them to size尺寸 12 --
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12乘12大小。
02:42
12 by 12.
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他无法再画下去了,
认为可能它们并不存在于
02:43
He couldn't不能 go any further进一步
and thought maybe they don't exist存在
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任何大于12尺寸的图中。
02:46
in any size尺寸 bigger than 12.
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因此他给照片中间这位
数学家写了一封信,
02:47
So he wrote a letter
to the mathematician数学家 in the middle中间,
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这是一位当时在加利佛尼亚州的
年轻数学家,所罗门 · 戈洛姆。
02:50
a young年轻 mathematician数学家 in California加州
at the time, Solomon所罗门 Golomb戈洛布.
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结果这位所罗门 · 戈洛姆
02:53
It turns out that Solomon所罗门 Golomb戈洛布
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是当时最具天赋的一位离散数学家。
02:55
was one of the most gifted天才 discrete离散的
mathematicians数学家 of our time.
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约翰问所罗门能否告诉他
02:59
John约翰 asked Solomon所罗门 if he could tell him
the right reference参考
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关于这些模式合适的参考。
03:02
to where these patterns模式 were.
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结果并没有任何东西可以借鉴。
03:03
There was no reference参考.
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在那以前没有人曾考虑过重复性,
03:05
Nobody没有人 had ever thought
about a repetition重复,
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一种无重叠结构。
03:07
a pattern-free无模式 structure结构体 before.
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03:09
So, Solomon所罗门 Golomb戈洛布 spent花费 the summer夏季
thinking思维 about the problem问题.
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因此,所罗门 · 戈洛姆用了
一个夏天思考这个问题。
他依靠这位绅士的数学成果,
03:13
And he relied on the mathematics数学
of this gentleman绅士 here,
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埃瓦里斯特 · 伽罗瓦(法国数学家)。
03:16
Évariste敏电阻器 Galois伽罗瓦.
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伽罗瓦是一位非常著名的数学家。
03:17
Now, Galois伽罗瓦 is a very
famous著名 mathematician数学家.
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他非常有名,因为他
创立了一个数学的分支
03:19
He's famous著名 because he invented发明
a whole整个 branch of mathematics数学
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并以他的名字命名,
叫做伽罗瓦域理论。
03:22
which哪一个 bears his name名称,
called Galois伽罗瓦 field领域 theory理论.
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这是关于质数的数学。
03:25
It's the mathematics数学 of prime主要 numbers数字.
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03:28
He's also famous著名
because of the way that he died死亡.
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他的一部分名气还源于他死去的方式。
03:32
The story故事 is that he stood站在 up
for the honor荣誉 of a young年轻 woman女人.
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传言他为了一位年轻
女性的荣誉挺身而出。
他接受了别人挑起的一场决斗。
03:35
He was challenged挑战 to a duel决斗,
and he accepted公认.
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03:38
And shortly不久 before the duel决斗 occurred发生,
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就在决斗开始前不久,
他写下了他所有的数学思想,
03:41
he wrote down all
of his mathematical数学的 ideas思路,
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并寄给了他所有的朋友们
说道“拜托,拜托,拜托”——
03:43
sent发送 letters to all of his friends朋友,
saying "Please, please" --
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这是200年前的事了--
03:46
this was 200 years年份 ago --
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“拜托,拜托,请无论如何
把这些东西发表出去。”
03:47
"Please, please, see that these things
get published发表 eventually终于."
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然后他便身赴决斗,
不幸中枪身亡,年仅20岁。
03:50
He then fought战斗 the duel决斗,
was shot射击 and died死亡 at age年龄 20.
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03:54
The mathematics数学 that runs运行
your cell细胞 phones手机, the internet互联网,
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那些允许你们在手机上,
因特网上进行交流,
以及播放DVD所运用到的数学,
03:57
that allows允许 us to communicate通信, DVDsDVD光盘,
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全都来自埃瓦里斯特 · 伽罗瓦的思想,
04:00
all comes from the mind心神
of Évariste敏电阻器 Galois伽罗瓦,
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这位年仅20岁就逝世的数学家。
04:03
a mathematician数学家 who died死亡 20 years年份 young年轻.
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因此,当你们讨论自己留下的遗产时——
04:06
When you talk about
the legacy遗产 that you leave离开 ...
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当然,他并没有想到
04:08
Of course课程, he couldn't不能 have
even anticipated预期
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他的数学思想将被如何运用。
04:10
the way that his mathematics数学
would be used.
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有幸的是,他的数学成果
最终被发表了。
04:12
Thankfully感激地, his mathematics数学
was eventually终于 published发表.
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所罗门 · 戈洛姆意识到那正
是他所需要的数学思想,
04:15
Solomon所罗门 Golomb戈洛布 realized实现 that that was
exactly究竟 the mathematics数学 needed需要
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用来解决创建出无模式架构的问题。
04:18
to solve解决 the problem问题 of creating创建
a pattern-free无模式 structure结构体.
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因此他写了封回信给约翰说道,
04:22
So he sent发送 a letter back to John约翰 saying,
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“结果证明你能用质数
理论来生成这些模式。”
04:25
"It turns out you can generate生成
these patterns模式 using运用 prime主要 number theory理论."
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于是约翰着手开始工作并为
海军解决了声纳定位问题。
04:28
And John约翰 went about and solved解决了
the sonar声纳 problem问题 for the Navy海军.
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04:34
So what do these patterns模式 look like again?
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那么这些模式看起来像什么?
这里有一个例子。
04:36
Here's这里的 a pattern模式 here.
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这是一个88乘88大小的
科斯塔斯阵列。
04:37
This is an 88-by--通过-88-sized-大小 Costas科斯塔斯 array排列.
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04:42
It's generated产生 in a very simple简单 way.
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它们通过一种非常简单的
方式生成出来。
利用小学数学就足以解决这个问题。
04:45
Elementary初级 school学校 mathematics数学
is sufficient足够 to solve解决 this problem问题.
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它们通过重复地乘以3产生出来:
04:49
It's generated产生 by repeatedly反复
multiplying乘以 by the number three:
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1, 3, 9, 27, 81, 243 ...
04:52
1, 3, 9, 27, 81, 243 ...
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当我们得到比89大同时
刚巧也是一个质数时,
04:57
When I get to a number that's larger
than 89 which哪一个 happens发生 to be prime主要,
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我持续减去89直到数字小于89。
05:01
I keep taking服用 89s away
until直到 I get back below下面.
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最终这些数字将填满
整个88乘88的网格。
05:04
And this will eventually终于 fill
the entire整个 grid, 88 by 88.
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在钢琴上正巧有88个音符。
05:08
There happen发生 to be 88 notes笔记 on the piano钢琴.
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所以今天,我们将听到世界上首次
05:11
So today今天, we are going to have
the world世界 premiere首映
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演奏的无重叠模式的钢琴奏鸣曲。
05:13
of the world's世界 first
pattern-free无模式 piano钢琴 sonata奏鸣曲.
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05:19
So, back to the question of music音乐:
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那么,回到音乐的问题上来:
是什么让乐曲听起来优美?
05:22
What makes品牌 music音乐 beautiful美丽?
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让我们想一想有史以来
最优美的乐曲之一:
05:23
Let's think about one of the most
beautiful美丽 pieces ever written书面,
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《贝多芬第五交响曲》,
最著名的“当当当当!” 的旋律。
05:26
Beethoven's贝多芬 Fifth第五 Symphony交响乐
and the famous著名 "daDA na na na!" motif主题.
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那段旋律在交响乐中出现了数百次——
05:31
That motif主题 occurs发生 hundreds数以百计
of times in the symphony交响乐 --
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光是第一乐章就有几百次,
05:34
hundreds数以百计 of times
in the first movement运动 alone单独
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同时也出现在所有其他的乐章中。
05:36
and also in all the other
movements运动 as well.
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因此建立这样的重复对于音
乐的优美性是非常重要的。
05:38
So the setting设置 up of this repetition重复
is so important重要 for beauty美女.
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如果我们想一段随机的
音乐,就像这些音符一样,
05:43
If we think about random随机 music音乐
as being存在 just random随机 notes笔记 here,
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贝多芬的第五交响曲就
以某种模式呈现出来,
05:47
and over here, somehow不知何故, Beethoven's贝多芬 Fifth第五
in some kind of pattern模式,
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如果我们写出一首
完全无重叠性的音乐,
05:50
if we wrote completely全然 pattern-free无模式 music音乐,
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将会在最结尾处。
05:52
it would be way out on the tail尾巴.
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实际上,音乐的结尾段落
正是这些无重叠的结构。
05:54
In fact事实, the end结束 of the tail尾巴 of music音乐
would be these pattern-free无模式 structures结构.
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这种我们刚刚看到的音乐,
那些在网格上的点点,
05:57
This music音乐 that we saw before,
those stars明星 on the grid,
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远远不是随机的。
06:01
is far, far, far from random随机.
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那是完完全全的无重叠。
06:05
It's perfectly完美 pattern-free无模式.
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06:07
It turns out that musicologists音乐学家 --
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结果音乐学者——
一位叫做阿诺尔德 · 勋伯格的著名作曲家——
06:10
a famous著名 composer作曲家 by the name名称
of Arnold阿诺德 Schoenberg舍恩贝格 --
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在20世纪30到50年代就想到过这些。
06:13
thought of this in the 1930s,
'40s and '50s.
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作为一位作曲家,他的目标是写出一段
06:16
His goal目标 as a composer作曲家 was to write music音乐
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没有音调结构的自由音乐。
06:19
that would free自由 music音乐
from tonal structure结构体.
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他称之为“不和谐音调的解放。”
06:22
He called it the "emancipation解放
of the dissonance不和谐."
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他创造出了这些称作“音列”的结构。
06:24
He created创建 these structures结构
called "tone rows."
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那儿显示了一段音列。
06:26
This is a tone row there.
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它听起来很像科斯塔斯阵列。
06:28
It sounds声音 a lot like a Costas科斯塔斯 array排列.
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不幸的是,他在科斯塔斯解决了
类似问题的十年前就去世了,
06:30
Unfortunately不幸, he died死亡 10 years年份
before Costas科斯塔斯 solved解决了 the problem问题
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这个问题是如何数学化
地创造出这些结构。
06:33
of how you can mathematically数学
create创建 these structures结构.
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06:37
Today今天, we're going to hear the world世界
premiere首映 of the perfect完善 ping.
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今天,我们将聆听世界上首次
演奏的完全无重叠的音乐。
这是一个88乘88大小的
科斯塔斯阵列,
06:42
This is an 88-by--通过-88-sized-大小 Costas科斯塔斯 array排列,
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映射到钢琴上的音符,
06:46
mapped映射 to notes笔记 on the piano钢琴,
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用称作戈洛姆标尺的结构作为节奏,
06:47
played发挥 using运用 a structure结构体 called
a Golomb戈洛布 ruler统治者 for the rhythm韵律,
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意思是每对音符的开始时间
06:51
which哪一个 means手段 the starting开始
time of each pair of notes笔记
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也是独一无二的。
06:53
is distinct不同 as well.
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这在数学上几乎是不可能的。
06:55
This is mathematically数学 almost几乎 impossible不可能.
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事实上,在计算机上
也不可能创造出来,
06:58
Actually其实, computationally计算,
it would be impossible不可能 to create创建.
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由于这种在200年前发明的数学,
07:00
Because of the mathematics数学
that was developed发达 200 years年份 ago,
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最近通过另一位数学家
和一位工程师,
07:04
through通过 another另一个 mathematician数学家
recently最近 and an engineer工程师,
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我们才能够谱出曲来,
或是赋予其架构,
07:07
we were able能够 to actually其实 compose撰写
this, or construct构造 this,
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通过使用乘3的运算。
07:10
using运用 multiplication乘法 by the number three.
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当你听到这段音乐时,重点是
07:12
The point when you hear this music音乐
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它不应该是优美的。
07:15
is not that it's supposed应该 to be beautiful美丽.
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它理应是世界上最难听的一段音乐。
07:17
This is supposed应该 to be
the world's世界 ugliest最丑 piece of music音乐.
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07:22
In fact事实, it's music音乐
that only a mathematician数学家 could write.
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事实上,这是一首只有数学家
才能谱写出的音乐。
07:25
(Laughter笑声)
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(笑声)
当你听到这段音乐时,我恳求你们:
07:26
When you're listening to this
piece of music音乐, I implore恳求 you:
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尝试找到一些重复性。
07:29
try and find some repetition重复.
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尝试找到一些你能享受的东西,
07:30
Try and find something that you enjoy请享用,
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然后陶醉于你其实不会找到的事实里。
07:33
and then revel陶醉 in the fact事实
that you won't惯于 find it.
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(笑声)
07:36
(Laughter笑声)
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好了,话不多说,
有请迈克尔 · 林维尔,
07:37
So without further进一步 ado忙乱, Michael迈克尔 Linville林维尔,
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新世界交响乐团室内乐的主任,
07:40
the [Dean院长] of Chamber商会 Music音乐
at the New World世界 Symphony交响乐,
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他将为大家演奏世界上
第一首无重叠乐曲。
07:43
will perform演出 the world世界 premiere首映
of the perfect完善 ping.
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07:47
(Music音乐)
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(音乐)
09:29
(Music音乐 ends结束)
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(音乐结束)
09:34
(Scott斯科特 Rickard里卡德, off-screen关屏) Thank you.
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(斯科特 · 里卡德,银屏后)
谢谢。
09:36
(Applause掌声)
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(掌声)
Translated by RUOSENG LUSHANG
Reviewed by Homer Li

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ABOUT THE SPEAKER
Scott Rickard - Mathematician
Scott Rickard is passionate about mathematics, music -- and educating the next generation of scientists and mathematicians.

Why you should listen

Scott Rickard is a professor at University College Dublin. His interest in both music and math led him to try and solve an interesting math problem: a musical score with no pattern. He has degrees in Mathematics, Computer Science, and Electrical Engineering from MIT, and MA and PhD degrees in Applied and Computational Mathematics from Princeton.

At University College Dublin, he founded the Complex & Adaptive Systems Laboratory, where biologists, geologists, mathematicians, computer scientists, social scientists and economists work on problems that matter to people. He is also the founder of ScienceWithMe!, an online community dedicated to engaging youth through science and math.

More profile about the speaker
Scott Rickard | Speaker | TED.com

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