原子有多小？剧透：非常小。：英语精读讲义

Atoms are ridiculous and unbelievably small.

原子小得离谱，难以置信。

A single human hair is about as thick as 500,000 carbon atoms stacked over each other. 語法

一根人类头发的厚度，大约相当于50万个碳原子叠在一起。

Look at your fist.

看看你的拳头。

It contains trillions and trillions of atoms. 短語搭配

里面包含着数以万亿计的原子。

If one atom in it were about as big as a marble, 語法

如果里面的一个原子有弹珠那么大，

how big would your fist be?

你的拳头会有多大？

Well, about the size of Earth.

嗯，大概有地球那么大。

Hmm, still hard to imagine?

唔，还是很难想象吗？

Let's try something different. 表達脈絡

我们换个方式试试。

Look at your little finger.

看看你的小拇指。

Imagine that its tip is as big as the room you're sitting in right now.

想象它的指尖有你现在坐的房间那么大。

Now, fill the room with grains of rice. 語法

现在，把这个房间装满大米。

One rice corn represents one cell of your fingertip.

一粒米代表你指尖上的一个细胞。

Now, let's zoom in on the rice corn. 短語動詞

现在，我们放大这粒米。

And now,

此时，

one cell is as big as the room you're in right now.

一个细胞就有你现在所在的房间那么大。

Let's fill it with rice again.

我们再次把它装满大米。

This is about the size of a protein. 短語搭配

这大约就是一个蛋白质的大小。

And now, let us fill all the empty spaces between the rice corns

现在，让我们把米粒之间的所有缝隙

with fine grains of sand.

都填满细沙。

This is roughly how small atoms are.

这就是原子大概的大小。

What is an atom made of? 短語搭配

原子是由什么构成的？

Let us just pretend that atoms look like this for a minute

我们先假装原子长这样，

to make it easier to understand.

以便更容易理解。

An atom consists of three elementary particles: 短語搭配

原子由三种基本粒子组成：

neutrons, protons, and electrons.

中子、质子和电子。

Protons and neutrons bind together and form the atom core,

质子和中子结合在一起形成原子核，

held together by the strong interaction, 文化背景

由强相互作用力维系，

one of the four fundamental forces in the universe.

这是宇宙四大基本力之一。

They are made from quarks and held together by gluons.

它们由夸克组成，并通过胶子结合在一起。

Nobody knows exactly how small quarks are. 語法

没人确切知道夸克有多小。

We think they might literally be points, 用詞

我们认为它们可能真的是点，

like in geometry.

就像几何学里的点一样。

Try to imagine them as being zero-dimensional.

试着把它们想象成零维的。

We suspect that quarks and electrons are the most fundamental components of matter in the universe.

我们怀疑夸克和电子是宇宙中最基本的物质成分。

Electrons orbit the atom core.

电子绕着原子核运行。

They travel at a speed of about 2,200 km/s,

它们以大约每秒2200公里的速度穿梭，

fast enough to get around the Earth in just over 18 seconds. 語法

快到只需18秒多一点就能绕地球一圈。

Like quarks,

就像夸克一样，

we think electrons are fundamental particles.

我们认为电子是基本粒子。

99.99999999999% of an atom's volume is just empty space, 表達脈絡

原子99.99999999999%的体积只是空无一物的空间，

except that it isn't.

但实际上并非如此。

What we perceive as emptiness is actually a space filled by quantum fluctuations, 講解

我们以为的虚空其实充满着量子涨落，

fields that have potential energy and build and dissolve spontaneously.

这些具有势能的场在自发地形成和消散。

These fluctuations have a fundamental impact on how charged particles interact, 短語搭配

这些涨落对带电粒子如何相互作用有着根本性的影响，

but that's a topic for another video. 表達脈絡

不过那是另一期视频的主题了。

How much space do the core and electrons actually fill?

原子核和电子实际上占据了多少空间？

If you were to subtract all the spaces between the atom cores from the Empire State Building, 文化背景

如果你把帝国大厦中原子核之间的所有空隙都去掉，

it would be about as big as a rice corn.

它差不多就只有一粒米那么大。

All the atoms of humanity would fit in a teaspoon.

全人类所有的原子加起来，只用一把茶匙就能装下。

There are extreme objects where states like this actually exist.

在一些极端的星体中，这种状态是真实存在的。

In a neutron star, 文化背景

在中子星里，

atom cores are compacted so densely 語法

原子核被压缩得极其紧密，

that the mass of three suns fits into an object only a few kilometers wide.

以至于三个太阳的质量都能被塞进一个只有几公里宽的天体中。

By the way, what do atoms look like? 表達脈絡

顺便问一下，原子到底长什么样？

Well, kind of like this. 短語搭配

嗯，大概像这样。

Electrons are like a wave function and a particle at the same time. 用詞

电子同时具有波函数和粒子的特性。

We can calculate where an electron might be at any given moment in time. 短語搭配

我们可以计算出电子在任何给定时刻可能出现的位置。

These clouds of probability, called orbitals, 用詞

这些被称为轨道的概率云，

are where electrons might be with a certainty of 95%.

就是电子有95%的概率出现的地方。

The probability of finding an electron approaches zero the further we get away from the atom core, 語法

我们离原子核越远，找到电子的概率就越接近于零，

but it actually never is zero,

但它永远不会真的是零，

which means that, in theory, 短語搭配

这就意味着，在理论上，

the electron of an atom could be on the other side of the universe.

一个原子的电子可能会在宇宙的另一端。

Okay, wait a second. 語氣意圖

等等，稍等一下。

These strange thingies make up all the matter in the universe. 講解

这些奇怪的小东西构成了宇宙中的所有物质。

For many dozens of known elements,

对于几十种已知元素来说，

you don't need many dozens of elementary particles,

你不需要几十种基本粒子，

just three.

只需要三种。

Take one proton and one electron, 語法

拿一个质子和一个电子，

and you have hydrogen.

你就得到了氢。

Add a proton and a neutron,

加一个质子和一个中子，

you have helium.

你就得到了氦。

Add a few more,

再加几个，

you get carbon.

你就得到了碳。

A few more, fluorine.

再加几个，得到氟。

Even more, gold.

再多点，得到金。

And so on.

以此类推。

And every atom of an element is the same.

一种元素的所有原子都是相同的。

All hydrogen atoms in the universe,

宇宙中所有的氢原子，

for example, are the same.

例如，都是一样的。

The hydrogen in your body is exactly the same as the hydrogen in the sun.

你体内的氢和太阳里的氢完全一模一样。

Do you feel confused right now?

你现在觉得困惑吗？

We certainly do. 語法

我们肯定是有点。

Nothing on this scale of the universe makes any sense in our world, 短語搭配

在我们这个世界里，宇宙的这种微观尺度是说不通的，

and we've not even begun talking about quantum mechanics or the particle zoo, 講解

而且我们甚至还没开始讨论量子力学或粒子动物园，

which are even stranger.

那些还要更加奇怪。

Our model of atoms has changed a number of times since we first conceived it, 語法

自从我们最开始构想出原子模型以来，它已经改变过好几次了，

and the current one will certainly not be the last.

而目前的模型肯定也不会是最后一个。

So, let us support scientists and research

所以，让我们支持科学家和科学研究，

and wait for the next wave of mind-boggling new information 講解

等待下一波令人震撼的新信息，

about this strange world

去了解这个奇妙的世界，

that is the basis for our existence.

这正是我们存在的基础。