1.In the year 1919, a virtually unknown German mathematician named Theodor Kaluza suggested a very bold and, in some ways, a very bizarre idea.
在1919年， 一位显为人知名叫“西奥多?卡鲁扎”的德国数学家 提出了一个大胆，甚至有些异乎寻常的猜想。
2.He proposed that our universe might actually have more than the three dimensions that we are all aware of.
他认为在我们的宇宙 可能实际上包含不只三个维度 并非像我们一贯所认为的那样。
3.That is in addition to left, right, back, forth and up, down, Kaluza proposed that there might be additional dimensions of space that for some reason we don’t yet see.
除了我们熟悉的左和右，前与后，上跟下外， “卡鲁扎”认为空间里可能包含有额外的维度 只是因为某些特殊原因，我们还无法认知。
4.Now, when someone makes a bold and bizarre idea, sometimes that’s all it is — bold and bizarre, but it has nothing to do with the world around us.
当一个人有了大胆怪异的猜想， 我们通常只会关注其大胆和古怪的部分， 而这部分和我们存在的现实世界是毫无关联的。
5.This particular idea, however — although we don’t yet know whether it’s right or wrong, and at the end I’ll discuss experiments which, in the next few years,
但是这一次，面对于这个猜想– 虽然我们还不知道它的正确与否， 之后我会谈谈一些会在未来几年里进行的实验，
6.may tell us whether it’s right or wrong — this idea has had a major impact on physics in the last century and continues to inform a lot of cutting-edge research.
可能会证实它的真伪– 这个猜想在上个世纪已经给物理学界带来了重大冲击 毫无疑问，它会进一步推动大量前沿学科的研究。
7.So I’d like to tell you something about the story of these extra dimensions.
所以，我想借此机会与你一起探讨一下这些“额外的维度”。
8.So where do we go?
我们从哪里开始好呢？
9.To begin we need a little bit of back story. Go to 1907.
先让我们谈一些背景知识吧。话说1907年，
10.This is a year when Einstein is basking in the glow of having discovered the special theory of relativity and decides to take on a new project —
那年“爱因斯坦”已经成功地 发现了狭义相对论 并且正计划开启一个新的课题研究–
11.to try to understand fully the grand, pervasive force of gravity.
进一步深入地发掘被大家普遍认知的重力的由来。
12.And in that moment, there are many people around who thought that that project had already been resolved.
那时，很多人 认为该课题早已被攻克了。
13.Newton had given the world a theory of gravity in the late 1600s that works well, describes the motion of planets, the motion of the moon and so forth,
“牛顿”已经在17世纪末提出了重力理论 该理论可以正确地描述了星球间的运动， 月亮的运动等等，
14.the motion of apocryphal of apples falling from trees, hitting people on the head.
但这个导致苹果坠落的令人质疑的运动， 一直困扰着大家。
15.All of that could be described using Newton’s work.
虽然这些运动都可以运用牛顿理论来描述，
16.But Einstein realized that Newton had left something out of the story, because even Newton had written that although he understood how to calculate the effect of gravity,
但是“爱因斯坦”意识到“牛顿”遗留下了一些未解的东西， 甚至“牛顿”本人也提到 虽然他明白如何计算“重力”的影响，
17.he’d been unable to figure out how it really works.
但是他无法真切地了解“重力”究竟是如何工作的。
18.How is it that the Sun, 93 million miles away, somehow it affects the motion of the earth?
为什么距离地球9千3百万英里外的太阳， 可以影响到地球的运动？
19.How does the Sun reach out across empty inert space and exert influence?
太阳是如何超越空旷无极的宇宙来施展它的魔力？
20.And that is a task to which Einstein set himself — to figure out how gravity works.
这恰恰是“爱因斯坦”想探讨地– 究竟“重力”是从何而来。
21.And let me show you what it is that he found.
让我们来看看他究竟发现了什么。
22.So Einstein found that the medium that transmits gravity is space itself.
“爱因斯坦”发现 传递“重力”的媒介其实就是空间本身。
23.The idea goes like this: imagine space is a substrate of all there is.
他的观点是这样的： 想象空间是承载万物的本源。
24.Einstein said space is nice and flat, if there’s no matter present.
“爱因斯坦”认为在没有任何物质存在的情况下，空间是细致扁平的。
25.But if there is matter in the environment, such as the Sun, it causes the fabric of space to warp, to curve.
但在有物质存在的情况下， 比如说太阳， 它会导致这个类似织布的空间扭曲。
26.And that communicates the force of gravity.
而这导致了“重力”的产生。
27.Even the earth warps space around it.
地球同样会扭曲在它四周的空间。
28.Now look at the moon.
你看月亮。
29.The moon is kept in orbit, according to these ideas, because it rolls along a valley in the curved environment that the sun and the moon and the earth can all create by virtue of their presence.
根据这个想法，月亮之所以能保持在它的轨道上， 是因为它沿着曲面的内测旋转 太阳，地球，月亮间的影响力均是因为它们本身的存在而产生的。
30.We go to a full-frame view of this.
我们来总体看一下。
31.The earth itself is kept in orbit because it rolls along a valley in the environment that’s curved because of the sun’s presence.
地球之所以保持在其轨道上 是因为它旋转的曲面是 太阳的存在而产生的。
32.That is this new idea about how gravity actually works.
这是一个崭新的关于“重力”由来的观点。
33.Now, this idea was tested in 1919 through astronomical observations.
随后，这个观点在1919年通过天文观测被肯定。
34.It really works. It describes the data.
这个观点能够正确的解释相关的数据。
35.And this gained Einstein prominence around the world.
这使得“爱因斯坦”在世界上名声大震。
36.And that is what got Kaluza thinking.
而这也促使了“卡鲁扎”去思考。
37.He, like Einstein, was in search of what we call a “unified theory.”
他和“爱因斯坦”一样，也在寻找我们称之的“统一理论”。
38.That’s one theory that might be able to describe all of nature’s forces from one set of ideas, one set of principles, one master equation, if you will.
一个理论 能够用来描述所有自然间的作用力，可以是一整套观点， 一整套法则，或者一条主宰万物的等式，用你的话来说。
39.So Kaluza said to himself, Einstein has been able to describe gravity in terms of warps and curves in space — in fact, space and time, to be more precise.
所以“卡鲁扎”自认为， “爱因斯坦”能够用扭曲的空间来 描述“重力”– 更精确的来说，用空间和时间。
40.Maybe I can play the same game with the other known force, which was, at that time, known as the electromagnetic force — we know of others today, but at that time
也许我也可以用相同的方式来描述其他已知的作用力， 也就是当时已经被认知的电磁力– 今天我们知道有更多的作用力，但在那个时期
41.that was the only other one people were thinking about.
电磁力是另一个唯一被大众所思索的。
42.You know, the force responsible for electricity and magnetic attraction and so forth.
你看，这种作用力反应了电场 和磁场的相互作用。
43.So Kaluza says, maybe I can play the same game and describe electromagnetic force in terms of warps and curves.
所以“卡鲁扎”认为，也许我可以用相同的方式 同样以“扭曲”为基点来描述电磁力。
44.That raised a question: warps and curves in what?
于是就有了进一步的问题：“扭曲”的依托是什么？
45.Einstein had already used up space and time, warps and curves, to describe gravity.
“爱因斯坦”已经借用了空间和时间， 并以其“扭曲”的结果来描述重力。
46.There didn’t seem to be anything else to warp or curve.
似乎没有什么别的什么依托对象来实施“扭曲”了。
47.So Kaluza said, well, maybe there are more dimensions of space.
于是“卡鲁扎”想，这样吧，也许空间里包含有更多的维度。
48.He said, if I want to describe one more force, maybe I need one more dimension.
他想，如果我要描述另一个作用力， 也许我需要增加一个维度。
49.So he imagined that the world had four dimensions of space, not three, and imagined that electromagnetism was warps and curves in that fourth dimension. Now here’s the thing:
所以他想象这个世界是由四个维度的空间组成，而不是三个， 并且电磁力的作用是在第四维度上 的“扭曲”而产生的。请注意这里：
50.when he wrote down the equations describing warps and curves in a universe with four space dimensions, not three, he found the old equations that Einstein had already derived in three dimensions —
当他在写方程式组来描述四度空间的“扭曲”， 不再是三度空间的时候， 他发现“爱因斯坦”以三度空间为模型构建的方程式组–
51.those were for gravity — but he found one more equation because of the one more dimension.
就是用来描述重力的– 因其添加了额外的一维空间而增加了一个方程式。
52.And when he looked at that equation.
当他查看这个方程式时，
53.It was none other than the equation that scientists had long known to describe the electromagnetic force.
发现没有别的方程式 被其他的科学家用来描述这个被熟知的电磁力。
54.Amazing — it just popped out.
太奇妙了–就这样被发现了。
55.He was so excited by this realization that he ran around his house screaming, “Victory!” — that he had found the unified theory.
对于这个发现，他万分激动 他围绕着房子边跑边叫，“成功喽！”– 他已经发现了“统一理论”。
56.Now clearly, Kaluza was a man who took theory very seriously.
很明显，“卡鲁扎”极为地偏重“理论”。
57.He, in fact — there is a story that when he wanted to learn how to swim, he read a book, a treatise on swimming — (Laughter) — then dove into the ocean.
他，实际上– 有一个故事，当他想要学习游泳的时候， 他读了本论述游泳的书– （大笑声） –然后就跳到海里去了。
58.This is a man who would risk his life on theory.
他就是这种将生命系于理论的人。
59.Now, but for those of us who are a little bit more practically-minded, two questions immediately arise from his observation.
你看，想我们这些稍微有些实践头脑的人， 就他的研究上，两个问题会立即产生。
60.Number one: if there are more dimensions in space, where are they?
第一个问题：如果空间中含有额外的维度，它们在哪里？
61.We don’t seem to see them.
似乎我们并没有观察到。
62.And number two: does this theory really work in detail, when you try to apply it to the world around us?
第二个问题：这个理论确实能真实详尽地 应用于我们的世界么？
63.Now the first question was answered in 1926 by a fellow named Oskar Klein.
第一个问题在1926年被 一个名叫“奥斯卡 克莱恩”的回答了。
64.He suggested that dimensions might come in two varieties — there might be big, easy-to-see dimensions, but there might also be tiny, curled-up dimensions,
他认为维度可能以两种形式存在– 一种维度可能很大，很容易被认知， 另一种可能很小，卷曲在一起的维度，
65.curled up so small, even though they’re all around us, that we don’t see them.
因为卷曲得太小了，虽然存在于我们周围， 但我们无法认知。
66.Let me show you that one visually.
请看这里的图像演示。
67.So imagine you’re looking at something like a cable supporting a traffic light.
设想你正在关注 一根支持交通灯的钢缆。
68.It’s in Manhattan. You’re in Central Park — it’s kind of irrelevant — but the cable looks one dimensional from a distant viewpoint,
是在曼哈顿。你正在中央公园– 好像跑题了– 从远处看，钢缆貌似是一维的，
69.but you and I all know that it does have some thickness.
但大家都知道钢缆是有粗细之分的。
70.It’s very hard to see it, though, from far away.
虽然从远处来看是非常难辩认的。
71.But if we zoom in and take the perspective of, say, a little ant walking around — little ants are so small that they can access all of the dimensions —
但如果我们聚焦来看，比如， 一只小蚂蚁在上面爬行着– 因为蚂蚁的微小，它可以穿越不同的维度–
72.the long dimension, but also this clockwise, counter-clockwise direction.
长的维度， 同样顺时针和逆时针的方向。
73.And I hope you appreciate this.
同时，我希望你们能感激我们所做的。
74.It took so long to get these ants to do this.
我们费了很大功夫才让蚂蚁做到了这些。
75.(Laughter) But this illustrates the fact that dimensions can be of two sorts: big and small. And the idea that maybe the big dimensions around us
（大笑声） 但这却阐明了维度可以有两种类型的事实： 大的和小的。 大的维度就存在于我们的周围
76.are the ones that we can easily see, but there might be additional dimensions curled up, sort of like the circular part of that cable,
我们可以轻易的识别， 但也可能存在有额外的卷曲维度， 就像钢缆的柱面，
77.so small that they have so far remained invisible.
因为过于微小而未被发掘。
78.Let me show you what that would look like.
让我们来看看它可能的形状。
79.So if we take a look, say, at space itself — I can only show, of course, two dimensions on a screen.
如果我们要看空间本身– 当然，在屏幕上只能显示两个维度。
80.Some of you guys will fix that one day, but anything that’s not flat on a screen is a new dimension, goes smaller, smaller, smaller,
将来你们之中的一些人会解决这个问题， 当然任何不处于平面上的部分是在一个新的维度上， 让我们深入，深入，再深入，
81.and way down in the microscopic depths of space itself — this is the idea: you could have additional curled up dimensions.
一直深入到细微的空间本身– 这里是关键： 空间里可以包含额外的卷曲维度。
82.Here is a little shape of a circle — so small that we don’t see them.
这就是小圆环–因为太小了所以我们无法观察到。
83.But if you were a little ultra microscopic ant walking around, you could walk in the big dimensions that we all know about — that’s like the grid part —
但如果你是超微小的爬行蚂蚁， 你既可以在我们公认的大维度上爬行– 就像在这些格子里–
84.but you could also access the tiny curled-up dimension that’s so small that we can’t see it with the naked eye or even with any of our most refined equipment.
也可以在微小的卷曲维度里自由进出 因为它实在太微小了，我们无法用肉眼直接看到 甚至用我们最精良的仪器也无法观测到。
85.But deeply tucked into the fabric of space itself, the idea is there could be more dimensions, as we see there.
但当深入到类似织布的空间本身， 可能会存在更多的维度，正像我们刚才看到的。
86.Now that’s an explanation about how the universe could have more dimensions than the ones that we see.
而这就是解释 为什么宇宙中能够包含有更多的维度而并非我们所习惯认知的。
87.But what about the second question that I asked: does the theory actually work when you try to apply it to the real world?
那么对于我刚才提出的第二个问题： 这个理论能够 被运用于实践么？
88.Well, it turns out that Einstein and Kaluza and many others worked on trying to refine this framework and apply it to the physics of the universe
其实，“爱因斯坦”，“卡鲁扎”以及其他 致力于优化这个体系 并试图将其应用于当时被认知到的宇宙物理学，
89.as was understood at the time, and in detail it didn’t work.
发现在细微处该理论并不能反应现状。
90.In detail, for instance, they couldn’t get the mass of the electron to work out correctly in this theory.
在细微处，比如说， 他们无法得到与理论计算 相一致的电子数。
91.So many people worked on it, but by the 40s, certainly by the 50s, this strange but very compelling idea of how to unify the laws of physics had gone away.
曾经很多人致力于此研究，但从40年代，确切地说50年代起， 这个奇怪但引人入胜的课题 关于如何统一物理学法则的想法没落了。
92.Until something wonderful happened in our age.
直到在我们这个年代，一些奇妙的事情发生了。
93.In our era, a new approach to unify the laws of physics is being pursued by physicists such as myself, many others around the world,
在我们的时代，物理学家们正在尝试用一种新的理论 来统一物理学，这其中包括我 也包括世界各地的物理学家
94.it’s called Superstring Theory, as you were indicating.
这种理论被称作“超弦理论”
95.And the wonderful thing is that superstring theory has nothing to do at first sight with this idea of extra dimensions, but when we study superstring theory,
“超弦理论”奇妙之处在于 乍一看它和多维度并没有什么关系 但是当我们深入研究“超弦理论”的时候
96.we find that it resurrects the idea in a sparkling new form.
我们发现它以一种崭新的方式使这个理念得以复苏
97.So let me just tell you how that goes.
下面让我来解释其中的道理
98.Superstring theory — what is it?
什么是“超弦理论”？
99.Well, it’s a theory that tries to answer the question: what are the basic fundamental indivisible uncuttable constituents making up everything in the world around us?
它是一个试图回答以下问题的理论 在这个世界上，围绕着我们的万事万物都是由什么样的 最基本的，不可再分的成分组成的？
100.The idea is like this.
这个理论的观点是
101.So imagine we look at a familiar object, just a candle in a holder, and imagine that we want to figure out what it is made of.
现在来想象一下我们观察一个熟悉的物体，一个烛托里的蜡烛 接着想象我们试图弄明白它的构成
102.So we go on a journey deep inside the object and examine the constituents.
于是我们展开一段旅程，进入到这个物体的深处来研究它的构成
103.So deep inside — we all know you go sufficiently far down, you have atoms.
我们到了内部足够深的地方，你看到了原子
104.We also all know that atoms are not the end of the story.
我们也知道原子并不是最小的单位
105.They have little electrons that swarm around a central nucleus with neutrons and protons.
我们看到微小的电子紧紧地围绕着中心的原子核 原子核中有中子和质子
106.Even the neutrons and protons have smaller particles inside of them known as quarks.
而在中子和质子里我们也能发现更小的粒子–夸克
107.That is where conventional ideas stop.
以上是以被广泛接受的观点
108.Here is the new idea of string theory.
现在我要讲的是弦理论提出的新观点
109.Deep inside any of these particles, there is something else.
在那些粒子的深处，还可以发现一些东西
110.This something else is this dancing filament of energy.
他们是正在舞动的丝状物，携带着能量
111.It looks like a vibrating string — that’s where the idea string theory comes from.
这些东西看上去像振动着的弦 这就是弦理论从何而来
112.And just like the vibrating strings that you just saw in a cello can vibrate in different patterns, these can also vibrate in different patterns.
就好像你看到的大提琴上的弦 能以不同的模式振动 这些弦也可以以不同模式振动
113.They don’t produce different musical notes.
他们不能产生各种音乐符号
114.Rather, they produce the different particles making up the world around us.
然而，他们制造出了围绕在我们周围，这个世界中的不同粒子
115.So if these ideas are correct, this is what the ultra-microscopic landscape of the universe looks like.
所以，如果这个理论是正确的话 这就是宇宙中极微观世界的情景
116.It’s built up of a huge number of these little tiny filaments of vibrating energy, vibrating in different frequencies.
它是由无数 微小的振动能量丝组成的 他们以不同的频率振动着
117.The different frequencies produce the different particles.
不同的频率产生不同的粒子
118.The different particles are responsible for all the richness in the world around us.
不同的粒子保证了 我们这个世界的多样性
119.And there you see unification, because matter particles, electrons and quarks, radiation particles, photons, gravitons, are all built up from one entity.
这样你就看到了统一性 因为不论是物质粒子，电子，夸克 还是放射性粒子，光子，引力子，都是由一种实体构成的
120.So matter and the forces of nature all are put together under the rubric of vibrating strings.
自然界中的物质和各种力都是由 这些震动着的红色弦组成的
121.And that’s what we mean by a unified theory.
这就是我们所说的统一理论
122.Now here is the catch.
但是问题是
123.When you study the mathematics of string theory, you find that it doesn’t work in a universe that just has three dimensions of space.
当你研究弦理论中的数学时 你会发现 它在我们这个只有三维空间的宇宙里是不成立的
124.It doesn’t work in a universe with four dimensions of space, nor five, nor six.
在四维，五维或六维的世界里也不成立
125.Finally, you can study the equations, and show that it works only in a universe that has 10 dimensions of space and one dimension of time.
最终，当你研究这些方程，你会发现 它只适用于一个有十个空间维度 和一个时间维度的世界
126.It leads us right back to this idea of Kaluza and Klein — that our world, when appropriately described, has more dimensions than the ones that we see.
这就是以前克鲁兹和卡莱恩的观点 当我们的世界被合理描述的时候 它的维度应该比我们肉眼看得到的要多
127.Now you might think about that and say, well, OK, you know, if you have extra dimensions, and they’re really tightly curled up, yeah, perhaps we won’t see them if they’re small enough.
稍加思索，也许你就会说， 好，你看，如果真的存在更多的维度，他们又紧紧地蜷缩起来 是啊，如果他们真的足够小的话，也许我们确实看不到他们
128.But if there’s a little tiny civilization of green people walking around down there, and you make them small enough and we won’t see them either, that is true.
但是如果有一群微小的绿色智人在下面行走 你可以想象让他们变得很小，小到我们眼不见他们，就是这样
129.One of the other predictions of string theory — no, that’s not one of the other predictions of string theory.
这个弦理论做出的一种预言 不，这并不是弦理论做出的另一种预言
130.(Laughter) But it raises the question: are we just trying to hide away these extra dimensions, or do they tell us something about the world?
（笑声） 但是它引发了一个问题 是我们企图把这些额外的维度隐藏起来呢 又或者他们向我们揭开世界的奥秘
131.In the remaining time, I’d like to tell you two features of them.
在接下来的时间里，我会向你们展示这些额外维度的两个特点
132.First is, many of us believe that these extra dimensions hold the answer to what perhaps is the deepest question in theoretical physics, theoretical science.
第一，我们中的很多人都相信这些额外的维度 可以解答也许是理论物理，理论科学中 最深层的问题
133.And that question is this: when we look around the world, as scientists have done for the last hundred years, there appear to be about 20 numbers that really describe our universe.
这个问题就是：当我们环顾这个世界， 在过去的几百年中，科学家们得出 大约有20个数字可以有力地描述我们生活的宇宙
134.These are numbers like the mass of the particles, like electrons and quarks, the strength of gravity, the strength of the electromagnetic force —
这些数字包括粒子的质量 包括电子和夸克，引力的强度 电磁力的强度
135.a list of about 20 numbers that have been measured with incredible precision, but nobody has an explanation for why the numbers have the particular values that they do.
这大约20个数字 已经被测量的极度精确 但是没人可以解释 为什么这些数字显示现在我们所测量出来的数值
136.Now, does string theory offer an answer?
那么，弦理论可以给出答案吗
137.Not yet.
现在还不行
138.But we believe the answer for why those numbers have the values they do may rely on the form of the extra dimensions.
但是我们相信关于上诉问题的答案 有可能有待这些额外维度的形态来解答
139.And the wonderful thing is, if those numbers had any other values than the known ones, the universe, as we know it, wouldn’t exist.
令人称奇的是，如果这些数字 换成了其他数值而非现在的数值 那么我们熟悉的宇宙就将灰飞烟灭了
140.This is a deep question.
这是个深奥的问题
141.Why are those numbers so finely tuned to allow stars to shine and planets to form, when we recognize that if you fiddle with those numbers —
为什么这些数字被如此精心地调试 使得恒星发光，行星得以形成 我们意识到，如果你扰乱这些数字
142.if I had 20 dials up here and I let you come up and fiddle with those numbers, almost any fiddling makes the universe disappear.
如果我把这个调高20 或者我让你上台来搅乱这些数字 几乎任何的干扰都会使宇宙消失
143.So can we explain those 20 numbers?
那么我们可以解释这20个数字吗？
144.And string theory suggests that those 20 numbers have to do with the extra dimensions.
弦理论认为，这20个数字 和额外的维度有关系
145.Let me show you how.
让我来向你们演示
146.So when we talk about the extra dimensions in string theory, it’s not one extra dimension, as in the older ideas of Kaluza and Klein.
所以当我们讨论到弦理论中的额外维度时 不是在讨论额外的一个维度 就像早期卡鲁扎和克莱因的观点
147.This is what string theory says about the extra dimensions.
这才是弦理论描述的额外维度
148.They have a very rich intertwined geometry.
他们有非常多样又错综复杂的几何图样
149.This is an example of something known as a Calabi-Yau shape — name isn’t all that important.
现在你看到的被称为Calabi-Yau形状 名字并不是重点
150.But as you can see, the extra dimensions fold in on themselves and intertwine in a very interesting shape, interesting structure.
但是你们可以看到 额外的维度嵌入他们之中 缠绕，呈现出一种引人入胜的形状，一个有趣的结构
151.And the idea is that if this is what the extra dimensions look like, then the microscopic landscape of our universe all around us would look like this on the tiniest of scales.
这个观点认为如果这就是这些额外维度的样子 那么我们身处的宇宙的在显微镜在呈现的景象 在如此微小的尺度中看上去就是这样的
152.When you swing your hand, you’d be moving around these extra dimensions over and over again, but they’re so small that we wouldn’t know it.
就在你的一摆手之间 你就来回穿梭在这些额外的维度里 但是他们太小了，我们不会察觉到
153.So what is the physical implication, though, relevant to those 20 numbers?
那么这20个数字隐含着什么物理意义呢？
154.Consider this. If you look at the instrument, a French horn, notice that the vibrations of the airstreams are affected by the shape of the instrument.
请这样来想。如果你看着这件乐器，一个法国圆号 你会注意到这些气流的震动 受乐器形状的影响
155.Now in string theory, all the numbers are reflections of the way strings can vibrate.
在弦理论中 所有这些数字反映了弦可以震动的方式
156.So just as those airstreams are affected by the twists and turns in the instrument, strings themselves will be affected by the vibrational patterns in the geometry within which they are moving.
所以就像这些气流 是受乐器弯曲旋转的影响 弦本身也受 震动模式的影响。而震动模式是由移动的几何图案决定的
157.So let me bring some strings into the story.
现在让我来阐述弦理论的原理
暂无讨论，说说你的看法吧
