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  • We take it for granted that our universe contains planets, stars and galaxies

    我們認為宇宙包含行星、星星和銀河為理所當然

  • because those are the things we see but the only reason these big structures

    因為那些是我們所能見到的,但這些大型物體存在的唯一原因為

  • exist is because of the nature of nothingness - empty space. But to

    虛無的本質---空無一物的太空

  • understand why we have to go back to the beginning. The very beginning. The big bang.

    但為了了解為什麼我們要追溯起源,最早的起源,大爆炸

  • You know, I always thought that in the Big Bang the observable universe

    你知道,我一直認為在大爆炸中,宇宙

  • started as a point and then just expanded steadily more or less to the

    起初為一個點,然後穩定膨脹到差不多

  • point that we're at today but that's not actually how it happened.

    現今的大小,然而事實並不如此

  • There were four different phases in the universe's expansion. To start it was expanding

    在宇宙的膨脹中有四個不同的階段。一開始她會穩定地膨脹

  • steadily but then after just a tiny fraction of a second the expansion just

    但在經過一個瞬間的小分裂後,宇宙的膨脹

  • blew up and the whole universe increased in size by like ten to the twenty six

    變大,整個宇宙的尺寸在短時間內增加十到二十六倍

  • times in a very short period of time and that period is known as inflation and

    那段時間就稱為膨脹

  • then just as abruptly as it began inflation stopped and after that the

    然後膨脹如開始一樣突然停止,在那之後

  • universe continued expanding but at a decreasing rate so the expansion of the

    宇宙以漸緩速度繼續膨脹,所以宇宙的膨脹

  • universe was actually slowing down which is exactly what you expect if the

    是如你預期地漸漸變慢的,如果

  • universe is full of massive objects that gravitationally attract each other

    宇宙充滿地心引力物質彼此吸引

  • but then about five or six billion years ago the expansion of the universe

    但在大約五六十億年前宇宙的膨脹

  • started speeding up again and this is thought to be caused by dark energy,

    開始重新加速,這個現象被認為是由暗能量所引起的

  • an energy tied to space. So before that time there was enough matter, the matter

    而暗能量是太空所具有的。所以在有足夠物質、

  • density was high enough, that it was pulling everything back together slowing

    物質密度夠高之前,所有東西拉在一起並減低

  • down the expansion but once the universe reached a critical size

    膨脹速度,但一旦宇宙達到一個臨界尺寸

  • well then there was enough dark energy to start pushing things apart and that

    就會有足夠的暗能量將物質分離,而那

  • is the phase that we're still in the expansion of the universe is accelerating.

    是宇宙膨脹加速的階段

  • Now, this story doesn't really explain the formation of galaxies

    這個故事並沒有真正解釋銀河的形成

  • until you tie in the nature of nothingness

    直到你將虛無本質連結在一起

  • now ordinarily we think of everything around us as made of particles of atoms

    現在我們一般都認為所有在我們身邊的物質都是由原子

  • and electrons but our best theories of physics are actually field theories that

    和電子所組成,但最好的物理解釋理論是場域理論

  • say all these particles should be seen as just excitations in fields.

    這理論闡述應該要將這些粒子視為場域中的激發態

  • The word "field" always gets me because it makes me think of... well, fields.

    「場域」這個字總是引起我興趣,因為它讓我想到......場域

  • but a field is just something that has a value everywhere in space.

    但一個場域是一個處處都有值的空間

  • So every subatomic particle has its own field: an electron field, an up quark field,

    所以每個微小原子例子都有它的場域:一個電子場域、一個上夸克場域

  • a down quark field, a neutrino field, and so on...

    一個下夸克場域、一個中微子場域等等

  • And anywhere there's an excitation in this field

    而場域內有激發態的地方

  • that is some energy in the field

    意味著在場域中有一些能量

  • well that is where we will observe particles. So out in completely empty

    而那正是我們觀察粒子的地方,所以在完全空

  • space where the values for all of these fields are basically zero.

    的地方,這些場域的數值基本上都是零

  • but here's the thing

    重點來了

  • it's impossible to make a field perfectly flat and 0.

    不可能會有場域是完全平坦且數值為零

  • You cannot take a quantum field and make it completely quiet.

    你不可能取一個量子場域並讓他完全安靜

  • It's the Heisenberg uncertainty principle.

    這是海森堡測不準原理

  • It says you can't take a particle and pinpoint it to exactly zero energy

    他敘述你不能取一個粒子並準確轟炸到零能量

  • likewise you can't take a quantum field and make it exactly flat everywhere.

    這就像是你不可能拿一個量子場域並讓他四處平坦

  • Now, this is important because ordinarily these fluctuations are really really

    現在這很重要,因為這些波動一般是非常非常

  • tiny and they only affect subatomic processes but during that period of

    微小,而且他們只會影響微原子過程,但在膨脹過程中

  • inflation the universe expanded in size so rapidly and so incredibly that those

    宇宙膨脹的非常快速以至於那些

  • tiny fluctuations got blown up to the scale of the observable universe

    微小波動擴大到可見宇宙的規模

  • Now, without them we think the matter distribution in the universe would have

    現在在沒有他們的情況下,我們認為宇宙中的物質分佈

  • been completely homogeneous completely uniform and that means the gravitational

    會完全同植、一致,而這意味著地心引力

  • force on any object in the universe would have been the same in all

    在宇宙中的任一物體上在任一方向會一樣

  • directions which means nothing would ever have collapsed into the big

    這意味著沒有東西會碰撞成現今的大型

  • structures that we see today but thanks to these fluctuations there were

    結構,但由於這些波動,會有

  • slightly denser and less dense regions and of course the denser regions had

    輕微較密集或較不密集的區域,當然較密集的區域會又

  • stronger gravitational fields so they pulled in the matter from around them

    較強的地心引力場域,所以他們會將圍繞周圍的物質拉在一起

  • and that clumped together the matter into huge gas clouds that would go on to be

    並形成可能會成為銀河的大型氣體雲

  • the galaxies that contain the stars and the planets and the things we know today

    裏頭會包含星星、行星還有那些我們現今知道的物質

  • you can actually see the imprint of these quantum fluctuations in the

    你可以看到這些量子波動的蹤跡

  • leftover radiation from the Big Bang the cosmic microwave background radiation

    在大爆炸宇宙微波背景輻射後所留下的輻射裡

  • the quantum fluctuations in the fields were amplified to big classical fluctuations

    場域中的量子波動也會放大成大的典型波動

  • in the density of

    各地的物質密度

  • matter from place to place and those fluctuations in the density of matter show up

    和物質密度的波動顯現

  • in the universe today as temperature differences in the cosmic background

    在現今宇宙,例如宇宙背景裡的溫度差異

  • radiation and ultimately in things like stars and planets and galaxies

    輻射和最終會成為星星、行星和銀河的東西

  • I think it is incredible that without these fluctuations in the vacuum these tiny

    我認為這是很不可思議的,因為沒有這些在真空裡的波動,這些微小

  • insignificant things that we take for granted our universe might really

    不起眼、讓我們視為理所當然的宇宙物質可能真的

  • contain nothing. Nothing of interest anyway...

    會空無一物,不再有令人值得探討的東西......

  • Speaking of vacuum

    說到真空

  • this episode was supported in part by Dyson who sent me their 360 eye vacuuming robot

    這個影片是由Dyson所贊助的,他寄給我360 eye吸塵機器人

  • it's got this little camera on the top that can see 360 degrees around it now

    他的頂部有這個可以看360度的小相機

  • it uses that vision plus some complex math and trigonometry to work out its

    現在他利用這個視角加上一些複雜的數學和三角學讓他

  • location precisely and to figure out where it's cleaned already and where it

    能準確定位並且了解哪裡已經清理過以及哪裡

  • still needs to clean it actually makes a map that you can see on your phone using

    還需要加強,他會做成一個地圖,而你可以透過dyson app在手機上看到

  • the dyson app and you can use that app also to control the vacuum or to

    你也可以用這個應用程式來控制吸塵器或是

  • schedule it even when you're not at home so I for one welcome robots taking over

    甚至當你不在家的時候也可對他做計畫,這個機器人會做

  • the housework you want to find out more you can click the link in the

    所有你想要做的家務,如果想知道更多的資訊,你可以點

  • description so i want to thank Dyson for supporting me and I want to thank my

    描述中的連結,我想謝謝Dyson

  • patreon supporters and of course you for watching

    patreon 支持者和在觀賞影片的你們的支持

We take it for granted that our universe contains planets, stars and galaxies

我們認為宇宙包含行星、星星和銀河為理所當然

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