Name: Andrea Ghez：尋找超大品質黑洞的過程 (Andrea Ghez: The hunt for a supermassive black hole)
Uploaded: 2021-01-14T07:26:02.000Z
Duration: 16 min 57 s

How do you observe something you can't see?

This is the basic question of somebody who's interested

如何观察那些你看不见的东西？

对于那些有兴趣寻找和研究黑洞的人来讲

that nothing can escape it, not even light,

there is a really massive, what we like to call

"supermassive" black hole at the center of our galaxy.

在我们这个星系是否存在一个巨大的

And the reason this is interesting is that

whether or not these exotic objects really exist.

这些奇异的东西是否真正地存在。

to understand how these supermassive black holes

and to understand how they affect the formation and evolution

它们所处星系的形成和演化提供了很好的机会。

we need to understand what a black hole is

so we can understand the proof of a black hole.

这样，我们才能找出黑洞存在的证据。

Well, in many ways a black hole is an incredibly simple object,

because there are only three characteristics that you can describe:

呃，从很多方面上讲，黑洞是一个相当简单的物体

因为只需三个特征就可以概括它：™

And I'm going to only talk about the mass.

So, in that sense, it's a very simple object.

But in another sense, it's an incredibly complicated object

从这个角度上来说，黑洞就简单了。

that we need relatively exotic physics to describe,

但从另外一个角度来讲，它又是相当的复杂

and in some sense represents the breakdown of our physical understanding

复杂到要用很奇特的物理学来描述它，

但这又在某种程度上说明了我们对宇宙的物理认识

But today, the way I want you to understand a black hole,

但是，今天，我想让大家这样理解黑洞

So, despite the fact that I'm going to talk to you about

and I'm going to get to what that really means in a moment,

But fortunately there is a finite size that you can see,

and that's known as the Schwarzschild radius.

幸运的是，我们还有具体的大小可供参照的，

And that's named after the guy who recognized

This is a virtual radius, not reality; the black hole has no size.

这个半径的重要性的人来命名的。

这并不是黑洞的实际半径，因为黑洞并无大小。

That means you, your neighbor, your cellphone,

也就是说你， 你的邻居，还有你的手机，

if you can figure out how to compress it down

甚至这个听众席，都可能变成黑洞，

如果可以的话，很发生什么呢？

Gravity wins over all other known forces.

And the object is forced to continue to collapse

引力战胜了我们所知的其他所有的力量。

So, if I were to compress the Earth down to the size of a sugar cube,

所以如果我把地球压缩到方糖般大小

because the size of a sugar cube is its Schwarzschild radius.

Now, the key here is to figure out what that Schwarzschild radius is.

因为方糖的大小就是地球的施瓦西半径的大小。

And it turns out that it's actually pretty simple to figure out.

现在，关键就是要解决施瓦西半径到底是多大了。

It depends only on the mass of the object.

Bigger objects have bigger Schwarzschild radii.

Smaller objects have smaller Schwarzschild radii.

and compress it down to the scale of the University of Oxford,

So, now we know what a Schwarzschild radius is.

And it's actually quite a useful concept,

现在我们知道施瓦西半径是什么了。

but it also gives us the key elements for the proof of a black hole.

同时也告诉我们找寻黑洞存在依据的关键

I need to understand the mass of the object

And since the mass determines the Schwarzschild radius,

there is actually only one thing I really need to know.

因为物体的质量决定了它的施瓦西半径，

that's confined to within its Schwarzschild radius.

被压缩到施瓦西半径的物体就可以了。

Okay, so, I'm going to talk about no ordinary black hole;

而你们就今天就先保持自己的怀疑态度吧。

I'm going to talk about supermassive black holes.

好，接下来我要讲的绝不是普通的黑洞；

So, I wanted to say a few words about what an ordinary black hole is,

as if there could be such a thing as an ordinary black hole.

在此，我先说说什么是普通的黑洞，

An ordinary black hole is thought to be the end state

with much more mass than the mass of the Sun,

而这个恒星的质量又远大于太阳，

and leaving behind these beautiful supernova remnants that we see here.

并留下我们见的那些漂亮的超新星残骸

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Andrea Ghez：尋找超大品質黑洞的過程 (Andrea Ghez: The hunt for a supermassive black hole)

massive

incredibly

figure

tremendous