String theory - Brian Greene

TED-Ed
9 Aug 201319:10

Summary

TLDR这个视频讲述了德国数学家卡卢扎在1919年提出的大胆假设,即我们的宇宙可能存在超过三个维度的空间。这一理论对20世纪的物理学产生了重大影响,并继续影响着前沿研究。视频还探讨了爱因斯坦如何通过广义相对论解释重力,并尝试寻找一个统一理论来描述自然界的所有力量。卡卢扎和克莱因的理论认为,额外的维度可能是微小且卷曲的,以至于我们无法观察到它们。弦理论的兴起为这一理论提供了新的支持,并且可能在未来几年内通过大型强子对撞机的实验得到验证。

Takeaways

  • 🌌 1919年,德国数学家卡卢扎提出了一个大胆的想法,即我们的宇宙可能存在超过三个维度的空间。
  • 🔍 爱因斯坦在1907年提出了广义相对论,解释了引力是由空间本身的弯曲造成的。
  • 🌐 卡卢扎的额外维度理论在1926年由奥斯卡·克莱因进一步发展,提出了微小的卷曲维度可能存在。
  • 🎻 超弦理论是一种尝试统一所有物理定律的新方法,它认为宇宙中的基本构成是由振动的弦组成。
  • 📈 弦理论的数学模型只有在存在十个空间维度和一个时间维度的宇宙中才有效。
  • 🔬 额外的维度可能对于解释宇宙中约20个基本常数的特定值具有关键作用。
  • 🌀 额外维度的复杂几何结构可能影响弦的振动模式,从而决定了宇宙中粒子的性质。
  • 💥 在CERN的大型强子对撞机上进行的实验可能在接下来的几年内直接测试额外维度的存在。
  • 🔋 如果在高能碰撞后测量到的能量少于碰撞前的能量,这可能是额外维度存在的证据。
  • 🌟 这些理论的发展和实验验证是人类对宇宙理解的一次重大飞跃,可能会揭示宇宙更深层次的秘密。
  • 🚀 从牛顿的绝对空间到爱因斯坦的弯曲空间,再到超弦理论的多维宇宙,我们对宇宙的认识正不断深化。

Q & A

  • Theodor Kaluza 提出了一个关于宇宙维度的什么大胆假设?

    -Theodor Kaluza 提出了我们的宇宙可能不仅仅包含我们所知的三个维度,而是存在额外的空间维度,这些维度由于某种原因我们目前还看不到。

  • 爱因斯坦是如何描述引力的?

    -爱因斯坦描述引力是通过空间本身作为传输介质。他提出,如果没有物质存在,空间是平坦的。但是,当有物质存在时,比如太阳,它会导致空间结构发生弯曲,从而传递引力。

  • 卡尔·施瓦西是如何尝试将电磁力与爱因斯坦的引力理论联系起来的?

    -卡尔·施瓦西尝试用类似描述引力的方式,即通过空间的弯曲和扭曲来描述电磁力。他想象如果存在第四个空间维度,那么电磁力就可以在这个额外的维度中以弯曲和扭曲的形式存在。

  • 奥斯卡·克莱因是如何解释额外维度的不可见性的?

    -奥斯卡·克莱因提出维度可能有两种类型:大到容易看到的维度和小到卷曲起来的维度。卷曲起来的维度可能非常小,即使它们就在我们周围,我们也看不见它们。

  • 超弦理论是如何复活了关于额外维度的概念的?

    -超弦理论是一种尝试回答世界基本构成要素的问题的理论。它提出所有物质和自然力都可以归结为振动的弦。当研究超弦理论的数学时,发现它只在存在十个空间维度和一个时间维度的宇宙中才有效,这复活了卡尔扎和克莱因关于额外维度的概念。

  • 额外维度可能对理解宇宙的基本参数有什么帮助?

    -许多科学家相信额外维度可能掌握着解释宇宙基本参数的钥匙。这些参数包括粒子的质量、重力的强度、电磁力的强度等,它们精确地决定了宇宙的结构和存在。

  • 大型强子对撞机(LHC)如何帮助我们测试额外维度的存在?

    -大型强子对撞机通过高能粒子碰撞实验,尝试将粒子从我们的维度推向额外维度。如果在碰撞后测量到的能量比碰撞前少,这将是额外维度存在的迹象。

  • 为什么说额外维度的发现对我们理解宇宙至关重要?

    -如果额外维度的发现得到证实,这将是对我们理解宇宙的一个重大突破。它不仅会验证超弦理论,还可能解释宇宙的基本参数为何具有当前的值,这些参数决定了宇宙的结构和我们的存在。

  • 卡尔·施瓦西的额外维度理论最初遇到了哪些问题?

    -卡尔·施瓦西的额外维度理论最初在细节上并不完全符合实际物理现象,例如,它无法正确解释电子的质量。这些问题导致这一理论在20世纪中叶被搁置。

  • 超弦理论中额外维度的几何结构是什么样的?

    -超弦理论中的额外维度具有非常丰富的、交织在一起的几何结构。这些维度以复杂的方式卷曲并相互缠绕,形成了一个微观层面上的复杂景观。

  • 弦理论是如何统一物质粒子和力的粒子的?

    -弦理论提出所有物质粒子和力的粒子都是由振动的弦构成的。不同的振动模式产生不同的粒子,这些粒子负责构成我们周围的世界,从而实现了物质和自然力的统一。

  • 未来几年内,科学家们如何可能验证额外维度的存在?

    -科学家们计划在未来几年内通过大型强子对撞机(LHC)进行高能粒子碰撞实验,通过观察碰撞后能量的变化来验证额外维度的存在。如果实验结果显示能量减少,这将是额外维度存在的第一个直接证据。

Outlines

00:00

🌌 卡尔萨斯的多维宇宙理论

这段视频脚本介绍了德国数学家卡尔萨斯在1919年提出的大胆而奇特的理论,即我们的宇宙可能不仅仅包含我们熟知的三个空间维度。卡尔萨斯提出,除了左右、前后和上下之外,可能还存在我们尚未观察到的其他空间维度。尽管这个想法当时看似离奇,但它对20世纪的物理学产生了重大影响,并继续影响着当今的前沿研究。视频还提到了爱因斯坦在1907年对重力的探索,以及他如何发现重力是通过空间本身传递的。卡尔萨斯的想法启发了后续的实验,这些实验可能在未来几年内揭示其正确与否。

05:01

🔍 额外维度的探索与理论

视频的第二段深入探讨了卡尔萨斯理论的后续发展。卡尔萨斯试图用额外的空间维度来描述电磁力,他设想如果存在第四个空间维度,电磁力就可以用这个维度中的弯曲和扭曲来解释。当他将这个想法写成数学方程时,意外地发现了一个描述电磁力的方程,这让他非常兴奋。然而,这个理论在细节上存在问题,例如无法正确解释电子的质量。直到20世纪中叶,这个理论才被重新审视,并在超弦理论中得到了新的生命。超弦理论试图回答一个基本问题:构成我们周围一切的基本、不可分割的组成部分是什么?

10:03

🎻 弦理论与基本粒子的构成

第三段视频脚本详细阐述了弦理论的基本概念,即所有物质和自然界的力都可以归结为振动的弦。在这个理论中,深入到物质的微观层面,我们会发现传统粒子物理学的终点——夸克和轻子内部,存在着类似能量弦的结构。这些弦的不同振动模式对应着不同的基本粒子,从而构成了我们周围的世界。这个理论的关键在于,它提供了一个统一的框架,将物质粒子和力的粒子统一为同一实体的不同表现形式。

15:05

🔬 测试额外维度的可能性

视频的最后一部分讨论了如何可能直接测试额外维度的存在。首先,它解释了额外维度可能对宇宙的基本参数产生影响,这些参数包括粒子的质量、重力和电磁力的强度等。弦理论认为,这些参数的特定值可能与额外维度的几何形状有关。此外,视频还提到了在欧洲核子研究中心(CERN)的大型强子对撞机(LHC)上进行的实验,这些实验可能在未来几年内为我们提供额外维度存在的直接证据。如果实验观察到粒子碰撞后能量的减少,并且这种减少符合特定模式,那么这将是额外维度存在的有力证据。

Mindmap

Keywords

💡Theodor Kaluza

Theodor Kaluza是一位德国数学家,他在1919年提出了一个非常大胆且在某些方面非常奇异的想法,即我们的宇宙可能实际上拥有超过三个我们所知的维度。这个概念虽然当时看起来奇特,但对20世纪的物理学产生了重大影响,并继续影响着许多前沿研究。

💡额外维度

额外维度是指除了我们日常生活中感知到的三个空间维度和一个时间维度之外,可能存在的其他空间维度。这些额外的维度可能是微小且卷曲的,以至于我们无法直接观察到它们。

💡爱因斯坦

爱因斯坦是20世纪最著名的物理学家之一,他提出了广义相对论,解释了重力是由物质对空间时间的曲率造成的。他的工作为理解宇宙的工作原理奠定了基础。

💡广义相对论

广义相对论是爱因斯坦提出的一个理论,它描述了重力是由物质对空间时间造成的曲率所传递的。这个理论在1919年通过天文观测得到了验证,并使爱因斯坦获得了世界范围内的声誉。

💡电磁力

电磁力是自然界四种基本相互作用之一,负责电和磁现象。在视频中,Kaluza尝试使用额外的空间维度来描述电磁力,这是他提出多维空间理论的动机之一。

💡超弦理论

超弦理论是一种尝试统一所有基本粒子和基本力的理论,它认为宇宙中的基本构成要素是微小的、像弦一样的振动能量。不同的振动模式对应着不同的粒子,从而构成了我们周围的世界。

💡维度的几何结构

维度的几何结构指的是额外维度可能具有的形状和结构。在超弦理论中,这些额外维度被认为是非常复杂和相互交织的,它们的形式可能影响到弦的振动模式,从而影响到我们宇宙的基本参数。

💡粒子物理学

粒子物理学是研究物质的基本组成和相互作用的物理学分支。在这个视频中,粒子物理学与额外维度的概念紧密相关,因为它探讨了基本粒子如何可能受到这些维度的影响。

💡大型强子对撞机

大型强子对撞机(LHC)是一个位于瑞士日内瓦的粒子加速器,它通过高速碰撞粒子来探索物质的基本结构和宇宙的基本原理。

💡宇宙的精细调谐

宇宙的精细调谐指的是宇宙中一些基本参数的精确值,这些参数的值如果稍有不同,就可能导致宇宙的消失或无法形成星星和行星。这些参数的精确调整至今仍是物理学中的一个未解之谜。

Highlights

1919年,一位鲜为人知的德国数学家Theodor Kaluza提出了一个大胆而奇特的想法,即我们的宇宙可能实际上拥有超过三个维度的空间。

除了我们熟知的左右、前后、上下三个空间维度外,Kaluza提出可能存在我们尚未看到的空间维度。

尽管这个想法当时看起来古怪,但它对20世纪的物理学产生了重大影响,并继续影响着许多前沿研究。

爱因斯坦在1907年发现了特殊相对论后,决定开始一个新项目,试图完全理解广泛而深远的重力力量。

牛顿在17世纪晚期提出了重力理论,很好地描述了行星、月球等的运动,但爱因斯坦意识到牛顿遗漏了一些关于重力如何实际工作的内容。

爱因斯坦发现,传递重力的介质是空间本身。当空间中存在物质,如太阳时,它会导致空间结构发生弯曲,从而传递重力。

1919年通过天文观测验证了爱因斯坦关于重力的理论,这使爱因斯坦在世界范围内获得了声誉。

Kaluza试图用额外的空间维度来描述当时已知的另一种力量——电磁力。

Kaluza的理论与爱因斯坦的相对论相结合,意外地得出了一个描述电磁力的新方程。

尽管Kaluza的发现令人兴奋,但实际应用中存在问题,例如无法正确计算电子的质量。

1926年,Oskar Klein提出了维度可能以大的容易看到和微小卷曲的形式存在,微小到我们看不见。

超弦理论是一种尝试回答世界基本构成要素是什么的理论,它提出所有物质和力量都来源于振动的能量弦。

超弦理论只有在一个具有十个空间维度和一维时间的宇宙中才有效。

超弦理论提出,我们宇宙的微观结构是由大量微小的、振动的能量弦构成的。

超弦理论可能解释了为什么宇宙中的某些基本参数具有它们特定的值。

在CERN的瑞士日内瓦,正在建造的大型强子对撞机可能在未来几年内测试额外维度的存在。

通过粒子碰撞实验,科学家们希望能够探测到额外维度的存在,这将是物理学史上的重大突破。

从牛顿的绝对空间到爱因斯坦的弯曲空间,再到超弦理论的多维宇宙,我们对宇宙的理解正在不断深化和扩展。

Transcripts

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in the year 1919 a virtually unknown

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German mathematician named Theodor

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Kaluza suggested a very bold and in some

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ways very bizarre idea he proposed that

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our universe might actually have more

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than the three dimensions that we are

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all aware of that is in addition to

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left-right back-forth and up-down gluts

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to propose that there might be

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additional dimensions of space that for

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some reason we don't yet see now when

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someone makes a bold and bizarre idea

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sometimes that all it is both bizarre

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but has nothing to do with the world

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around us this particular idea however

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although we don't yet know whether it's

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right or wrong and at the end I'll

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discuss experiments which in the next

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few years may tell us whether it's right

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or wrong this idea has had a major

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impact on physics in the last century

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and continues to inform a lot of

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cutting-edge research so I'd like to

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tell you something about the story of

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these extra dimensions so where do we go

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to begin need a bit of backstory go to

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1907 this is a year when Einstein is

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masking the glow of having discovered

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the special theory of relativity and

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decides to take on a new project to try

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to understand fully the grand pervasive

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force of gravity and in that moment

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there were many people around who

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thought that that project had already

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been resolved Newton had given the world

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the theory of gravity late 1600s that

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works well describes the motion of

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planets the motion of the moon and so

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forth the motion of apocryphal apples

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falling from trees hitting people in the

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head all of that could be described

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using Newton's work but Einstein

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realized that Newton had left something

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out of the story because even Newton had

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written that although he understood how

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to calculate the effect of gravity he

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had been unable to figure out how it

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really works how is it that the Sun 93

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million miles away somehow defect

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the motion of the earth how does the Sun

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reach out across empty inert space and

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exert influence and that as a task to a

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Jain Stein set himself to figure out how

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gravity works and let me show you what

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it is that he found so Einstein found

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that the medium that transmits gravity

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is space itself the idea goes like this

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imagine space is a substrate of all

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there is Einstein said space is nice and

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flat if there's no matter present but if

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there is matter in the environment such

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as the Sun it causes the fabric of space

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to warp to curve and that communicates

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the force of gravity even the earth

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warps space around it now look at the

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moon the moon is kept in orbit according

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to these ideas because it rolls along a

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valley in the curved environment that

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the Sun and the moon and the earth can

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all create by virtue of their presence

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we go to a full frame view of this the

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earth itself is kept in orbit because it

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rolls along a valley in the environment

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that's curved because of the sun's

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presence that is this new idea about how

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gravity actually works now this idea was

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tested in 1919 through astronomical

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observations it really works it

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describes the data and this gained

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Einstein prominence around the world and

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that is what got Colusa thinking he like

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Einstein was in search of what we call a

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unified theory that's one theory that

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might be able to describe all of

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nature's forces from one set of ideas

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one set of principles one master

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equation if you will so Coolidge's said

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to himself

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Einstein has been able to describe

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gravity in terms of warps and curves in

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space in fact space and time to be more

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precise maybe I can play the same game

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with the other known force which was at

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that time known as the electromagnetic

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force we know of others today but at

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that time that was the only other one

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people were thinking about you know the

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force responsible for electricity and

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magnetic attraction and so forth so

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Colusa says maybe I can play the same

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game and describe electromagnetic force

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in terms of warps and curves

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that raised a question warps and curves

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in what Einstein had already used up

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space and time warps and curves to

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describe gravity didn't seem to be

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anything else to warp a curve so Colusa

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said well maybe there are more

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dimensions of space

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he said if I want to describe one more

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force maybe I need one more dimension so

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he imagined that the world had four

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dimensions of space not three and

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imagine that electromagnetism was warps

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and curves in that fourth dimension now

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here's the thing when he wrote down the

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equations describing warps and curves in

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the universe with four space dimensions

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not three he found the old equations

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that einstein had already derived in

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three dimensions those were for gravity

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but he found one more equation because

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of the one more dimension and when he

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looked at that equation it was none

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other than the equation that scientists

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had long known to describe the

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electromagnetic force amazing it just

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popped out he was so excited by this

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realization that he ran around his house

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screaming victory that he had found the

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unified theory now clearly Colusa was a

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man who took theory very seriously he in

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fact there's a story that when he wanted

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to learn how to swim he read a book a

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treatise on swimming then toven to the

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ocean this is a man who would risk his

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life on theory now but for those of us

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who are a little bit more practically

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minded to questions immediately arise

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from his observation number one if there

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are more dimensions of space where are

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they we don't seem to see them and

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number two does this theory really work

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in detail when you try to apply it to

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the world around us now the first

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question was answered in 1926 by a

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fellow named Oskar Klein

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he suggested that dimensions might come

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in two varieties there might be big easy

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to see dimensions but there might also

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be tiny curled up dimensions curled up

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so small even though they're all around

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us that we don't see them let me show

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you that one visually so imagine you're

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looking at something like a cable

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supporting a traffic lights in Manhattan

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in Central Park that's it's kind of

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irrelevant but the cable looks

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one-dimensional from a distant viewpoint

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but you and I all know that it does have

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some thickness it's very hard to see it

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though from far away but if we zoom in

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and take their perspective to say a

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little ant walking around little ants

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are so small that they can access all

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the dimensions the long dimension but

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also this clockwise counterclockwise

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direction and I hope you appreciate this

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it took so long to get these ants to do

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this but this illustrates the fact that

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dimensions can be of two sorts big and

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small and the idea is that maybe the big

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dimensions around us are the ones that

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we can easily see but there might be

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additional dimensions curled up sort of

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like the circular part of that cable so

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small that they have so far remained

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invisible let me show you what that

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would look like so if we take a look say

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at space itself I can only show of

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course two dimensions on a screen some

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of you guys will fix that one day but

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anything that's not flat in the screen

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is a new dimension goes smaller smaller

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smaller and way down in the microscopic

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depths of space itself this is the idea

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you could have additional curled up

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dimensions here is a little shape of a

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circle so small that we don't see them

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but if you were a little

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ultra-microscopic ant walking around you

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can walk in the big dimensions that we

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all know about that's like the grid part

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but you could also access the tiny

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curled up dimension that's so small that

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we can't see with the naked eye or even

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with any of our most refined equipment

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but deeply tucked into the fabric of

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space itself the idea is there could be

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more dimensions as we see there now

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that's an explanation about how the

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universe could have more dimensions than

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the ones that we see but what about the

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second question that I asked does the

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theory actually work when you try to

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apply it to the real world well it turns

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out that Einstein includes and many

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others worked on trying to refine this

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framework and apply it to the physics of

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the universe as was understood at the

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time and in detail it didn't work in

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detail for instance they couldn't get

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the mass of the electron to work out

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correctly in this theory so many people

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worked on it but by the 40s certainly by

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the 50s

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this strange but very compelling idea of

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how to unify the laws of physics had

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gone away until something wonderful

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happened in our age in our era a new

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approach to unify the laws of physics is

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being pursued by physicists such as

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myself many others around the world it's

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called super string theory as you were

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indicating and the wonderful thing is

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that super string theory has nothing to

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do at first sight with this idea of

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extra dimensions but when we study super

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string theory we find that it resurrects

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the idea in a sparkling new form so let

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me just tell you how that goes super

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string theory what is it

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well it's a theory that tries to answer

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the question what are the basic

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fundamental indivisible uncuttable

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constituents making up everything in the

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world around us the idea is like this so

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imagine we look at a familiar object

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just a candle and a holder and imagine

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that we want to figure out what it is

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made of so we go on a journey deep

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inside the object and examine the

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constituents so deep inside we all know

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you go sufficiently far down you have

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atoms we also all know that atoms are

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not the end of the story

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they have little electrons that swarm

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around a central nucleus with neutrons

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and protons even the neutrons and

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protons have smaller particles inside of

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them known as quarks that is where

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conventional ideas stop here is the new

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idea of string theory deep inside any of

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these particles there is something else

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there's something else is this dancing

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filament of energy it looks like a

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vibrating string that's where the idea

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of string theory comes from and just

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like the vibrating strings that you just

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saw on a cello can vibrate in different

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patterns these can also vibrate in

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different patterns they don't produce

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different musical notes rather they

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produce the different particles making

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up the world around us so these ideas

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are correct this is what the

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ultra-microscopic landscape of the

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universe looks like it's built up of a

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huge number of these little tiny

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filaments of vibrating energy vibrating

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in different frequencies the different

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frequencies produce the different

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particles the different particles are

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responsible for all the richness

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in the world around us and there you see

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unification because matter particles

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electrons and quarks radiation particles

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photons

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gravitons are all built up from one

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entity so matter and the forces of

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nature all are put together under the

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rubric of vibrating strings and that's

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what we mean by a unified theory and

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here is the catch when you study the

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mathematics of string there you find

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that it doesn't work in a universe that

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just has three dimensions of space

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it doesn't work in a universe with four

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dimensions of space nor 5 nor 6

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finally you can study the equations and

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show that it works only in a universe

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that has ten dimensions of space and one

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dimension of time leads us right back to

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this idea of Kaluza and Klein that our

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world when appropriately described has

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more dimensions than the ones that we

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see now you might think about that and

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say well ok you know if you have extra

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dimensions and they're really tightly

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curled up yeah perhaps perhaps we won't

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see them if they're small enough but you

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know if there's a little tiny

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civilization of green people walking

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around down there you make them small

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enough and we won't see them either that

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is true one of the other predictions of

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string theory no that's not one of the

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other predictions of string theory but

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it raises the question are we just

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trying to hide away these extra

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dimensions or do they tell us something

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about the world and the remaining time

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I'd like to tell you two features of

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them first is many of us believe that

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these extra dimensions hold the answer

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to what perhaps is the deepest question

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in theoretical physics theoretical

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science and that question is this when

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we look around the world as scientists

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have done for the last hundred years

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there appear to be about 20 numbers that

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really describe our universe these are

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numbers like the mass of the particles

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like electrons and quarks the strength

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of gravity the strength of the

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electromagnetic force a list of about 20

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numbers that have been measured with

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incredible precision but nobody has an

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explanation for why the numbers have the

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particular values that they do now

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the string theory often answer not yet

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but we believe the answer for why those

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numbers have devised they do may rely on

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the form of the extra dimensions and the

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wonderful thing is if those numbers had

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any other values than the known ones the

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universe as we know it wouldn't exist

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this is a deep question why those

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numbers so finely tuned to allow stars

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to shine and planets to form when we

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recognize that if you fiddle with those

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numbers if I had 20 dials up here and

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I'll let you come up and fiddle with

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those numbers almost any fiddling makes

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the universe disappear so can we explain

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those twenty numbers and string theory

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suggests that those twenty numbers have

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to do with the extra dimensions let me

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show you how so when we talk about the

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extra dimensions in string theory it's

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not one extra dimension as in the older

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ideas of Kaluza and Klein this is what

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string theory says about the extra

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dimensions they have a very rich

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intertwined geometry this is an example

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of something known as a claw be a shape

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name isn't all that important but as you

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can see the extra dimensions fold in on

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themselves and intertwine in a very

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interesting shape interesting structure

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and the idea is that if this is what the

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extra dimensions look like then the

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microscopic landscape of our universe

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all around us would look like this on

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the tiniest of scales when you swing

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your hand you'd be moving around these

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extra dimensions over and over again but

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they're so small that we wouldn't know

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it so what is the physical implication

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though relevant to those twenty numbers

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consider this if you look at the

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instrument of French horn notice that

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the vibrations of the airstreams are

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affected by the shape of the instrument

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now in string theory all the numbers are

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reflections of the way strings can

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vibrate so just as those air streams are

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affected by the twists and turns in the

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instrument strings themselves will be

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affected by the vibrational patterns and

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the geometry within which they are

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moving so let me bring some strings into

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the story and if you watch these little

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fellas vibrating around they'll be here

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in a second right there notice that the

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way they vibrate is affected by the

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geometry of the extra dimensions so if

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we knew exactly what the extra

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dimensions look like we don't yet but if

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we

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we should be able to calculate the

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allowed notes the allowed vibrational

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patterns and if we could calculate the

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allowed vibrational patterns we should

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be able to calculate those 20 numbers

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and if the answer that we get from our

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calculations agrees with the values of

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those numbers that have been determined

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through detailed and precise

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experimentation this in many ways would

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be the first fundamental explanation for

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why the structure of the universe is the

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way it is now the second issue that I

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want to finish up with is how might we

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test for these extra dimensions more

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directly is this just an interesting

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mathematical structure that might be

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able to explain some previously

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unexplained features of the world or can

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we actually test for these extra

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dimensions and we think this is I think

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very exciting that in the next five

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years or so we may be able to test for

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the existence of these extra dimensions

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here's how it goes in CERN Geneva

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Switzerland a machine is being built

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called a Large Hadron Collider it's a

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machine that will send particles around

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a tunnel opposite directions near the

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speed of light every so often those

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particles will be aimed at each other so

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there's a head-on collision the hope is

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that if the collision has enough energy

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it may act some of the debris from the

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collision from our dimensions forcing it

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to enter into the other dimensions how

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would we know it well we'll measure the

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amount of energy after the collision

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compare it to the amount of energy

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before and if there's less energy after

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the collision than before this will be

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evidence that the energy has drifted

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away and if it drifts away in the right

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pattern that we can calculate this will

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be evidence that the extra dimensions

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are there let me show you that idea

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visually so imagine we have a certain

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kind of particles called a graviton

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that's the kind of debris we expect to

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be ejected out if the extra dimensions

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are real but here's how the experiment

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will go

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you take these particles you slam them

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together you slam them together and if

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we are right some of the energy of that

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collision will go into debris that flies

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off

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into these extra dimensions so this is

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the kind of experiment that we will be

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looking at in the next five seven to ten

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years or so and if this experiment bears

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fruit if we see that kind of particle

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ejected by noticing that there's less

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energy in our dimensions then when we

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began this will show that the extra

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dimensions are real and to me this is a

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really remarkable story and a remarkable

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opportunity going back to Newton with

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absolute space didn't provide anything

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but an arena a stage in which the events

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of the universe take place

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Einstein comes along and says well space

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and time can warp and curve that's what

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gravity is and now string theory comes

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along and says yes gravity quantum

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mechanics electromagnetism all together

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in one package but only if the universe

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has more dimensions than the ones that

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we see and this is an experiment that

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may test for them in our lifetime

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amazing possibility thank you very much

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