什麼是暗物質與暗能量？：英語精讀講義

Matter, as we know it,

物質，正如我們所知，

atoms, stars and galaxies,

原子、恆星和星系，

planets and trees,

行星和樹木，

rocks and us.

岩石和我們。

This matter accounts for less than 5% of the known universe. 片語動詞

這些物質佔已知宇宙的不到5%。

About 25% is dark matter and 70% is dark energy,

大約25%是暗物質，70%是暗能量，

both of which are invisible. 文法

兩者都是不可見的。

This is kind of strange

這有點奇怪，

because it suggests that everything we experience

因為這意味著我們經歷的一切

is really only a tiny fraction of reality. 片語搭配

實際上只是現實的一小部分。

But it gets worse. 表達脈絡

但情況比這更糟。

We really have no clue what dark matter and energy are, 片語搭配

我們真的不知道暗物質和暗能量是什麼，

or how they work.

或者是如何運作的。

We are pretty sure they exist, though. 語氣意圖

儘管如此，我們非常確定它們的存在。

So, what do we know? 表達脈絡

那麼，我們到底知道些什麼？

Dark matter is the stuff that makes it possible 文法

暗物質是使得

for galaxies to exist.

星系能夠存在的東西。

When we calculated why the universe is structured the way it is, 文法

當我們計算宇宙為何呈現目前的結構時，

it quickly became clear that there's just not enough normal matter. 片語搭配

很快就清楚地發現正常物質根本不夠。

The gravity of the visible matter

可見物質的引力

is not strong enough to form galaxies and complex structures. 文法

不足以形成星系和複雜的結構。

The stars would more likely be scattered all over the place 講解

恆星更有可能會散佈在各處，

and not form galaxies.

而不會形成星系。

So, we know there is something else inside and around them.

所以我們知道，在它們內部和周圍還有其他東西。

Something that doesn't emit or reflect light. 表達脈絡

不發光也不反射光的東西。

Something dark.

某種暗的東西。

But besides being able to calculate the existence of dark matter, 文法

但除了能夠計算出暗物質的存在，

we can see it, kind of. 語氣意圖

某種程度上，我們還能「看到」它。

Places with a high concentration of dark matter 片語搭配

暗物質高度集中的地方，

bend light passing near by.

會使經過附近的光發生彎曲。

So, we know there's something there that interacts with gravity.

所以我們知道，那裡存在著與引力交互作用的東西。

Right now, we have more ideas about what dark energy is not 文法

目前，關於暗能量「不是」什麼，我們的想法

than what it is.

甚至多於它「是」什麼。

We know dark matter is not just clouds

我們知道暗物質不只是

of normal matter without stars,

沒有恆星的正常物質雲，

because it would emit particles we could detect.

因為那樣它會發出我們可以探測到的粒子。

Dark matter is not antimatter,

暗物質不是反物質，

because antimatter produces unique gamma rays when it reacts with normal matter.

因為反物質在與正常物質反應時會產生獨特的伽馬射線。

Dark matter is also not made up of black holes, 片語動詞

暗物質也不是由黑洞組成的，

very compact objects that violently affect their surroundings,

（黑洞是極其緻密、會劇烈影響周圍環境的物體），

while dark matter seems to be scattered all over the place. 文法

而暗物質似乎散佈在各處。

Basically, we only know three things for sure. 表達脈絡

基本上，我們只有三件事是確定的。

One, something is out there. 片語搭配

一，外面有某種東西。

Two, it interacts with gravity.

二，它與引力交互作用。

Three, there is a lot of it.

三，它的數量很多。

Dark matter is probably made up of a complicated exotic particle

暗物質可能是由一種複雜的奇異粒子組成的，

that doesn't interact with light and matter in a way we expect. 文法

它不以我們預期的方式與光和物質發生交互作用。

But right now, we just don't know.

但現在，我們就是不知道。

Dark energy is even more strange and mysterious.

暗能量甚至更加奇怪和神秘。

We can't detect it, 表達脈絡

我們無法探測到它，

we can't measure it,

無法測量它，

and we can't taste it.

也無法嚐到它。

But we do see its effects very clearly. 文法

但我們非常清楚地看到了它的影響。

In 1929,

在1929年，

Edwin Hubble examined how the wavelength of light emitted by distant galaxies 文化背景

愛德溫·哈伯研究了遙遠星系發出的光波長，

shifts towards the red end of the electromagnetic spectrum as it travels through space.

在穿過太空時如何向電磁波譜的紅端移動。

He found that fainter, more distant galaxies

他發現更暗淡、更遙遠的星系

showed a large degree of redshift.

表現出很大程度的紅移。

Closer galaxies, not so much. 語氣意圖

較近的星系則沒那麼多。

Hubble determined that this was because the universe itself is expanding.

哈伯斷定，這是因為宇宙本身正在膨脹。

The redshift occurs because the wavelengths of light

發生紅移是因為光波長

are stretched as the universe expands. 文法

隨著宇宙的膨脹被拉長了。

More recent discoveries have shown that 片語搭配

近期的發現表明

the expansion of the universe is accelerating.

宇宙的膨脹正在加速。

Before that, it was thought that the pull of gravity would cause the expansion to either slow down 文法

在此之前，人們認為引力的拉力會導致膨脹變慢，

or even retract and collapse in on itself at some point. 片語動詞

甚至在某個時刻收縮並自我坍縮。

Space doesn't change its properties as it expands.

空間在膨脹時並沒有改變其性質。

There's just more of it.

它只是變得更多了。

New space is constantly created everywhere.

新的空間在各個地方不斷產生。

Galaxies are tight-bound clusters of stuff held together by gravity, 片語動詞

星系是由引力緊密結合在一起的物質團，

so we don't experience this expansion in our daily lives.

所以我們在日常生活中感覺不到這種膨脹。

But we see it everywhere around us.

但我們在周圍隨處可見其跡象。

Wherever there is empty space in the universe, 文法

宇宙中任何有空曠空間的地方，

more is forming every second.

每一秒都在形成更多的空間。

So, dark energy seems to be some kind of energy 語氣意圖

所以，暗能量似乎是某種

intrinsic to empty space. 片語搭配

空曠空間固有的能量。

Energy that is stronger than anything else we know

這種能量比我們已知的任何東西都要強，

and that keeps getting stronger as time passes by. 文法

並且隨著時間的推移越來越強。

Empty space has more energy

空曠空間的能量

than everything else in the universe combined.

比宇宙中所有其他東西的總和還要多。

We have multiple ideas about what dark energy might be.

我們對暗能量可能是什麼有多種想法。

One idea is that dark energy is not a thing, 文法

一種想法是，暗能量不是一個實體，

but just a property of space.

而只是空間的一種屬性。

Empty space is not nothing. 文法

空曠空間並非虛無。

It has its own energy.

它擁有自己的能量。

It can generate more space and is quite active.

它可以產生更多的空間，且非常活躍。

So, as the universe expands,

因此，隨著宇宙的膨脹，

it could be that 文法

可能是

just more and more space appears to fill the gaps, 文法

出現了越來越多的空間來填補空隙，

and this leads to a faster expanding universe. 片語搭配

這導致宇宙膨脹得更快。

This idea is close to an idea

這種想法很接近

that Einstein had back in 1917

愛因斯坦在1917年提出的

of a concept of a cosmological constant, 文化背景

宇宙常數的概念，

a force that counteracted the force of gravity.

即一種抵消引力的力。

The only problem is that 表達脈絡

唯一的問題是，

when we tried to calculate the amount of this energy,

當我們試圖計算這種能量的數量時，

the result was so wrong and weird that it only added to the confusion. 文法

結果極其離譜且怪異，只會增加困惑。

Another idea is that empty space is actually full of temporary virtual particles

另一種想法是，空曠的空間其實充滿了短暫的虛粒子，

that spontaneously and continually form from nothing 表達脈絡

它們自發且不斷地從虛無中形成，

and then disappear into nothing again.

然後又消失在虛無中。

The energy from those particles could be dark energy.

那些粒子的能量可能就是暗能量。

Or maybe dark energy

或者，暗能量

is an unknown kind of dynamic energy fluid or field,

是一種未知的動態能量流體或場，

which permeates the entire universe,

瀰漫在整個宇宙中，

but somehow has the opposite effect on the universe 片語搭配

但不知何故，它對宇宙的影響

than normal energy and matter.

與正常能量和物質的作用正好相反。

But if it exists,

但如果它存在，

we don't know how and where, 文法

我們不知道它在哪裡、運作方式，

or how we could detect it.

或我們如何探測它。

So, there are still a lot of questions to answer.

所以，仍有很多問題亟待解答。

Our theories about dark matter and dark energy are still just that, 語氣意圖

我們關於暗物質和暗能量的理論仍然只是，

theories.

理論而已。

On the one hand, this is kind of frustrating. 表達脈絡

一方面，這讓人有些沮喪。

On the other hand, this is frontier science,

但另一方面，這是前沿科學，

making it very exciting. 文法

讓人非常激動。

It shows us that no matter how much we feel we're on top of things, 講解

它向我們表明，不管我們覺得自己多麼能掌控一切，

we're still very much apes with smartphones 慣用語

我們很大程度上仍是拿著智慧型手機的猿猴，

on a tiny fragile island in space,

待在太空中一座脆弱的小島上，

looking into the sky, 文法

仰望星空，

wondering how our universe works.

思考著我們的宇宙是如何運轉的。

There is so much left to learn, 文法

還有這麼多東西要去學習，

and that is awesome.

這簡直太棒了。

This video is supported by the Australian Academy of Science,

本影片由澳洲科學院支持贊助，

which promotes and supports excellence in science.

該機構致力於促進和支持卓越科學。

Learn more about this topic and others like it at nova.org.au.

在nova.org.au了解有關此主題及類似主題的更多資訊。

It was a blast to work with them, 慣用語

和他們合作非常愉快，

so go check out their site.

去看看他們的網站吧。

Our videos are also made possible by your support on patreon.com.

我們的影片製作也離不開你們在patreon.com上的支持。

If you want to support us and become part of the Kurzgesagt bird army,

如果你想支持我們並成為Kurzgesagt鳥軍團的一員，

check out our Patreon page.

請造訪我們的Patreon頁面。