你並不在你以為的那個地方：英語精讀講義

Look around you.

環顧你的四周。

Where are you?

你在哪裡？

Where is this place you're occupying?

你所在的這個地方在哪裡？

Somewhere in a room, maybe in a city,

在某個房間裡，也許在某個城市，

on a continent, on a planet orbiting a star in a galaxy among billions.

在某個大陸上，在某個星球上，這顆星球正繞著數十億個星系中的某顆恆星運行。

But where is all of that?

但這一切又在哪裡呢？

While this may feel like a daft question,

雖然這聽起來像個蠢問題，

it turns out that the concept of an absolute position is something humans made up. 表達脈絡

但事實上，絕對位置的概念是人類編造出來的。

In a nutshell, 慣用語

簡而言之，

the universe is a big bag of space that has things in it.

宇宙就是一個裝著東西的大空間袋。

If someone removed all these things,

如果有人把這些東西全都拿走，

the stars and planets and black holes and dust,

恆星、行星、黑洞和塵埃，

there would just be empty space left.

那就只剩下空無一物的空間。

In empty space, the concept of having a position loses all meaning. 片語搭配

在空無一物的空間裡，擁有位置的概念就失去了任何意義。

Empty space is uniform, the same everywhere.

空無一物的空間是均勻的，到處都一樣。

The space we occupy is not like a stage under our feet. 慣用語

我們佔據的空間不像我們腳下的舞台。

We can't mark specific points or staple something to space-time as an anchor. 慣用語

我們無法標記特定的點，也不能把某個東西釘在時空上當作錨。

Without things, there is no position.

沒有東西，就沒有位置。

We are really ever only at a position in relation to something else,

我們實際上永遠只能處於相對於其他東西的位置，

which also means that things we take for granted 慣用語

這也意味著那些我們覺得理所當然的事物

like up and down are actually relative too.

像是上和下，其實也都是相對的。

Okay, let's fill the universe up with things again

好吧，讓我們再次用東西把宇宙填滿，

and try to find out where you are right now 片語動詞

並試著找出你現在相對於其他所有事物

relative to everything else.

所在的位置。

Let's start this video at a familiar place 表達脈絡

讓我們從一個熟悉的地方開始這段影片，

and then get increasingly weird.

然後事情會變得越來越離奇。

From your perspective,

從你的視角來看，

the world is seemingly flat and you can move in three dimensions.

世界看起來是平的，你可以在三個維度中移動。

It's what physicists call a frame of reference, 用詞

這就是物理學家所說的「參考系」，

the perspective you have of the universe

這是你觀察宇宙的視角，

and how you see things moving around you,

也是你看待事物在你周圍移動的方式，

where your up and down is.

決定了哪裡是你的上和下。

Your frame of reference is correct for you,

你的參考系對你來說是正確的，

but not for the rest of the universe.

但對宇宙的其他部分則不然。

Around 5 km from you,

在距離你約五公里外，

where the horizon begins,

地平線開始的地方，

the ground noticeably curves away from you.

地面明顯地向下彎曲。

If you could see through the ground, 文法

如果你能看透地面，

you'd see people from below or sideways.

你會看到從下方或側邊來的人。

But they don't fall down off the planet

但他們不會從這顆星球上掉下去，

because gravity doesn't actually pull them down.

因為重力並不會真的把他們「往下拉」。

Down is an illusion of your reference frame.

「下」只是你的參考系產生的錯覺。

To Earth's reference frame,

對於地球的參考系來說，

gravity just pulls in.

重力只是把東西「往內拉」。

But for humans, there is an up and down

但對人類來說，有上和下，

because within our frame of reference, that just makes sense,

因為在我們的參考系中，這才說得通，

which is also why we think that the planet itself has an up and down,

這也是為什麼我們認為這顆星球本身也有上和下，

north and south,

也就是北和南，

and we made our maps accordingly.

並且我們據此繪製了地圖。

But an observer looking at the solar system might disagree.

但一個觀察太陽系的觀察者可能會有不同的看法。

Our maps make sense to us because we're used to them, 文法

我們的地圖對我們來說有意義，是因為我們習慣了，

not because they are correct.

而不是因為它們是正確的。

Okay, so this is step one.

好的，這是第一步。

Your position on what feels like a flat surface,

你身處在一個感覺像平面的地方，

but is actually a sphere.

但實際上是個球體。

But this sphere is always moving,

而且這個球體總是在移動，

never staying in one position.

永遠不會停在同一個位置。

Earth is orbiting a star,

地球繞著一顆恆星運行，

the sun at the center of the solar system.

也就是太陽系中心的太陽。

While we usually imagine this as pretty orderly,

雖然我們通常想像這一切非常有秩序，

someone looking at us from the outside would see something pretty messy.

但從外面看我們的人會覺得這相當混亂。

To see this more clearly,

為了看清楚這點，

we'll exaggerate all these movements.

我們會把這些移動誇大。

This is not to scale. 片語搭配

這並非按實際比例繪製。

First of all, our orbit really is an ellipse,

首先，我們的軌道實際上是一個橢圓，

so we spend half the year sinking a little bit closer to the sun, 文法

所以我們有一半的時間會沉得更靠近太陽一點，

speeding up,

並且加速，

and half the year rising up a bit and slowing down.

而另一半的時間會稍微上升並減速。

And the ellipse itself changes its shape every 100,000 years too.

且橢圓本身每十萬年也會改變一次形狀。

And in another cycle of 112,000 years,

在另一個十一萬兩千年的週期裡，

the ellipse itself is drifting,

橢圓本身也在漂移，

which at least creates a beautiful shape.

這至少創造出了一個美麗的形狀。

In the end, we get an orbital path

最終，我們得到了一個軌道圖形，

that looks like a wobbly circle with wavy edges.

看起來像是一個邊緣呈波浪狀、搖擺不定的圓。

And it gets worse

而且情況還會變得更糟，

as the moon now starts to mess things up too. 片語動詞

因為月球現在也開始來攪局了。

As the moon is a pretty massive thing,

因為月球是個質量相當大的東西，

it pulls on Earth.

它會拉扯地球。

Both objects orbit their common center of gravity

這兩個天體繞著它們共同的重心運行，

that lies around 4,700 km off to the side of Earth's core.

這個重心距離地核側邊約四千七百公里。

In practice, this means that as the moon orbits Earth, 表達脈絡

實際上，這意味著當月球繞地球運行時，

it's jerking Earth around a bit, 片語動詞

它會稍微拉扯地球，

enough to make it jiggle.

足以讓地球晃動。

Okay, so you're standing on the surface of a rotating planet

好的，所以你站在一顆旋轉著的行星表面，

that is jiggling around the sun in an elliptical orbit

這顆行星以橢圓軌道繞著太陽晃動，

that changes a bit every year.

而且軌道每年都會發生些微變化。

But who's to say the Earth is right? 慣用語

但誰能說地球才是對的呢？

From the perspective of the sun,

從太陽的視角來看，

the plane of the solar system is arbitrary.

太陽系的平面是任意的。

It's defined as the plane the Earth orbits in 片語搭配

它被定義為地球運行的平面，

because that is convenient for us.

因為這樣對我們來說比較方便。

In reality, the other planets are just a little bit inclined

實際上，相較於我們的平面，

with respect to our plane. 片語搭配

其他行星只有一點點的傾斜。

From their point of view, 表達脈絡

從它們的角度來看，

we're the ones with a slightly bent orbit.

軌道稍微彎曲的其實是我們。

But this isn't it, far from it. 慣用語

但這還沒完，差得遠呢。

The solar system as a whole 片語搭配

整個太陽系

is orbiting the center of the Milky Way galaxy.

正繞著銀河系的中心運行。

If we look at the Milky Way,

如果我們看看銀河系，

we can clearly make out a galactic plane 片語動詞

可以清楚地辨識出一個銀河平面，

in which the solar system orbits the center every 230 million years.

太陽系在這個平面上每兩億三千萬年繞中心一圈。

But of course, it's not that simple.

當然，事情沒那麼簡單。

First of all, the plane of the solar system

首先，太陽系的平面

is not aligned with the plane of the galaxy.

並沒有與銀河系的平面對齊。

Nothing really is,

實際上什麼都沒有對齊，

just like the planets in the solar system orbit the sun on their own planes, 文法

就像太陽系中的行星在各自的平面上繞著太陽運行一樣，

so do all the stars orbiting the galactic center.

所有繞著銀河系中心運行的恆星也是如此。

The solar system as a whole is tilted about 60 degrees towards the galactic plane,

整個太陽系朝銀河平面傾斜了大約六十度，

speeding through space at almost a million kilometers per hour.

以將近每小時一百萬公里的速度在太空中穿梭。

Someone in the center of the galaxy

位於銀河系中心的人

would see the orbits of the planets moving through space in a helix shape,

會看到行星軌道在太空中呈螺旋狀移動，

which you can imagine as a corkscrew motion on the tilted plane of the solar system 表達脈絡

你可以把它想像成在傾斜的太陽系平面上相對於銀河平面的

relative to the plane of the galaxy.

開瓶器運動。

This orientation in space means that sometimes

在太空中的這種方位意味著，有時

the planets are sort of in front of the sun 語氣意圖

行星有點像是在太陽的前方，

as it orbits around the galactic core.

隨著太陽繞著銀河系核心運行。

Let's just look at this for a moment.

讓我們看著這個畫面一會兒。

There is a strange and eerie beauty

有一種奇特而詭異的美感，

about how our planets and the sun move through space.

在於我們的行星和太陽如何在太空中移動。

Do you feel a bit dizzy?

你覺得有點頭暈嗎？

It gets worse.

還有更糟的。

This is still not the whole story

這還不是故事的全部，

because the mass of the galactic disc

因為銀河系盤面的質量

is constantly pulling on the solar system too.

也不斷地在拉扯太陽系。

Like a drunk dolphin,

就像一隻喝醉的海豚，

we're diving down and shooting up hundreds of light-years

我們沿著數千光年長的弧線，

through the galactic plane 10 times every orbit

在每個軌道週期裡穿過銀河平面十次，

along arcs thousands of light-years long.

上下俯衝、竄升數百光年。

We haven't mapped this motion out completely 片語動詞

我們還沒有完全描繪出這個運動的軌跡，

as it takes the solar system tens of millions of years to go up and back once,

因為太陽系需要數千萬年才能完成一次上下起伏，

and well, humanity is not that old.

嗯，而人類的歷史還沒那麼悠久。

Let's look at your relative position again,

讓我們再次看看你的相對位置，

on a planet tilted towards the sun,

你在一顆朝向太陽傾斜的星球上，

jiggled around by the moon,

被月球拉扯著晃動，

in a solar system tilted towards the galactic plane,

位在一個朝銀河平面傾斜的太陽系中，

moving forward in a helical shape,

以螺旋狀的姿態向前移動，

diving up and down through the plane.

在平面中上下穿梭。

Hmm, but where is up in a galaxy?

嗯，但在銀河系中，哪裡才是「上」呢？

At this point,

在這一點上，

the frame of reference becomes a bit arbitrary and pointless

由於這個尺度的宇宙本質，

because of the nature of the universe at this scale.

參考系變得有些任意且沒有意義。

The Milky Way is part of a galaxy group

銀河系是一個星系群的一部分，

that appears to be part of greater structures

這個星系群似乎又是更大結構的一部分，

like the Laniakea supercluster,

像是拉尼亞凱亞超星系團，

which itself is part of the gigantic Pisces-Cetus supercluster complex,

而它本身又是巨大的雙魚-鯨魚座超星系團複合體的一部分，

and finally a galactic filament that spans hundreds of millions of light-years

最後是一個跨越數億光年、

in all directions and orientations.

向各個方向和方位延伸的星系纖維結構。

Someone looking right at us from that far away

如果有人從那麼遠的地方直接看著我們，

will only see the end of greatness.

只會看到「宏觀尺度的盡頭（End of Greatness）」。

All stuff appears homogeneous, the same everywhere.

所有東西看起來都是均勻的，到處都一樣。

Just like with empty space, when everything looks the same,

就像空無一物的空間一樣，當所有東西看起來都一樣時，

who's to say anyone's view is better than anyone else's?

誰能說誰的視角比別人的更好呢？

We've reached the end of our little exercise in cosmic humility. 慣用語

我們的這場宇宙謙卑小練習已經到了尾聲。

Let's make the journey backwards again,

讓我們再次倒轉這趟旅程，

from the indescribably large to the really large

從無法形容的巨大到非常巨大，

to our galactic home,

回到我們的銀河系家園，

to our galaxy,

回到我們的星系，

to the solar system

回到太陽系，

diving up and down through the Milky Way,

回到在銀河系中上下穿梭，

to the jiggle of existence,

回到存在的晃動，

and finally back to you right now watching this video.

最後回到正在觀看這部影片的你。

If this is all a bit much, 慣用語

如果這一切讓你覺得有點難以承受，

don't feel bad. 語氣意圖

別覺得難過。

The scale of the universe is brain-crushing

宇宙的尺度大到讓人腦袋當機，

and trying to keep track of how everything is oriented 片語搭配

試圖追蹤一切是如何定向，

or decide where the best up and down is is hard. 文法

或是決定哪裡才是最正確的上下，是一件很困難的事。

But it doesn't really matter

但這其實並不重要，

because it doesn't change where you are.

因為這並不會改變你所在的位置。

You're already in the best spot you possibly could be,

你已經身處在你能處於的最好位置上了，

right here, right now. 片語搭配

就在此時，就在此地。

For all you care,

就你在乎的而言，

nothing can stop you from being right at the center 慣用語

沒有什麼能阻止你

of your own little universe.

正好位於你自己小小宇宙的中心。