Maybe it's the fact that for a black hole to exist, a star must die.

也許是因為黑洞要存在，恆星就必須死亡。

Or maybe it's the fact that whatever goes into one cannot escape.

也可能是因為無論什麼東西進入其中都無法逃脫。

Or the idea that in the heart of a black hole, time and space don't work how we expect them to.

或者說，在黑洞的中心，時間和空間並不像我們期望的那樣運行。

Whatever the answer is, black holes, and especially what lies in their center, the so-called singularity, are the most enigmatic phenomena in the universe.

無論答案是什麼，黑洞，尤其是位於黑洞中心的所謂奇點，都是宇宙中最神祕的現象。

For over a hundred years, we've been living in the universe defined by Albert Einstein.

一百多年來，我們一直生活在愛因斯坦定義的宇宙中。

His theory of general relativity made it possible to explain everything from the origin of the universe to the orbits of the planets.

他的廣義相對論使人們有可能解釋從宇宙起源到行星軌道的一切問題。

His theory was revolutionary, but Einstein never imagined the astronomical phenomena we now know as black holes.

他的理論是革命性的，但愛因斯坦從未想象過我們現在所知的黑洞這一天文現象。

These are regions in space where gravity is so powerful that nothing, not even light, can escape once it enters.

這些空間區域的引力非常強大，任何東西，甚至光，一旦進入就無法逃脫。

And even though the first image of a black hole would only be taken in 2019, the proof of its existence was already there, in Einstein's equations.

儘管第一張黑洞影像要到 2019 年才能拍攝到，但愛因斯坦的方程已經證明了黑洞的存在。

But he refused to accept it because he didn't think that such a thing could exist.

但他拒絕接受，因為他認為這種事情不可能存在。

Accepting the existence of black holes would have meant recognizing that at its center hides the singularity, where all the laws of nature as we know them stop working.

如果接受黑洞的存在，就意味著承認黑洞的中心隱藏著奇點，在那裡，我們所知的所有自然法則都停止了作用。

Einstein's decisive rejection of black holes, which he published in the most respected mathematics journal in the world, created an obstacle to their investigation.

愛因斯坦在世界上最權威的數學雜誌上發表了他對黑洞的果斷否定，這對黑洞的研究造成了障礙。

After all, the father of general relativity was saying that they were impossible.

畢竟，廣義相對論之父曾說它們是不可能的。

But in 1965, physicist Roger Penrose managed to demonstrate mathematically that in Einstein's universe singularities are not only possible, but inevitable.

但 1965 年，物理學家羅傑-彭羅斯（Roger Penrose）用數學方法證明，在愛因斯坦的宇宙中，奇點不僅是可能的，而且是不可避免的。

It was because of his findings that Penrose was awarded the Nobel Physics Prize in 2020 at 89 years old.

正是因為他的研究成果，彭羅斯在 2020 年以 89 歲的高齡獲得了諾貝爾物理學獎。

However, the complete acceptance of black holes by the scientific community doesn't mean that all its mysteries were solved, much less the ones related to singularity.

然而，科學界對黑洞的完全認可並不意味著黑洞的所有謎團都已解開，更不用說與奇點有關的謎團了。

These concepts are very complex, so I'll start explaining the formation of black holes using something more common.

這些概念非常複雜，所以我先用一些更常見的東西來解釋黑洞的形成。

This wooden table.

這張木桌

You can see a table and feel that it's solid, but its density is just a few grams by cubic centimeter.

你可以看到一張桌子，感覺到它是實心的，但它的密度只有幾克/立方厘米。

And the scale of black holes, this material, is too light.

而黑洞的尺度，這種物質，太輕了。

To turn this table into a black hole, we would have to compress it until its density became incredibly high.

要想把這張桌子變成黑洞，我們必須把它壓縮到密度高得驚人的程度。

The problem is that this material will resist compression.

問題是這種材料會產生抗壓縮性。

And the more I try to squeeze it, the more I put pressure on it, the bigger its resistance will be.

我越想擠壓它，給它施加的壓力越大，它的阻力就越大。

We would need a very powerful event in order to generate enough energy around the table to compress it to a volume so small and so dense that it creates a black hole.

我們需要一個非常強大的事件，才能在桌子周圍產生足夠的能量，把它壓縮到如此小的體積，如此高的密度，以至於形成一個黑洞。

One type of event capable of liberating such an amount of energy is a supernova.

能夠釋放如此巨大能量的一種事件是超新星。

That's what happens when a massive star, meaning a star that is at least 30 times larger than our sun, dies and, in a matter of seconds, explodes.

這就是大品質恆星（指比我們的太陽至少大 30 倍的恆星）死亡並在幾秒鐘內爆炸時發生的情況。

After that, it collapses in on itself, forming a black hole.

之後，它就會自我坍縮，形成一個黑洞。

This process is responsible for the formation of stellar black holes, which are the most common ones.

這一過程是恆星黑洞形成的原因，而恆星黑洞是最常見的黑洞。

According to the most recent calculations, there are between 10 million and a billion of them in the Milky Way alone.

根據最新的計算，僅銀河系中就有 1 000 萬到 10 億個這樣的天體。

There is also another type of black hole called supermassive, which astronomers believe lie in the center of almost all the major galaxies, including ours.

還有另一種類型的黑洞，叫做超大品質黑洞，天文學家認為這種黑洞幾乎位於所有主要星系的中心，包括我們的星系。

In fact, Penrose didn't win the Nobel Prize alone.

事實上，彭羅斯並非獨自獲得諾貝爾獎。

He shared it with Andrea Ghez and Reinhard Genzel, who discovered an object in the center of our galaxy, believed to be one of these supermassive black holes.

他與安德烈亞-蓋茲（Andrea Ghez）和萊因哈特-根澤爾（Reinhard Genzel）分享了這一發現，他們在銀河系中心發現了一個天體，據信就是這種超大品質黑洞之一。

I say believed to be because what they know is that in this region there is an invisible object which is so heavy that it causes all the stars around it to move at impressive speeds.

我之所以說 "相信"，是因為他們知道在這個地區有一個看不見的物體，它非常重，以至於它周圍的所有恆星都在以驚人的速度移動。

To understand why this could be a black hole, we have to think about our celestial bodies with mass and imagined space, which is technically called space-time, as an elastic bed.

要理解為什麼這可能是一個黑洞，我們必須把有品質的天體和想象中的空間（技術上稱為時空）想象成一張有彈性的床。

But let's take it slow.

但我們還是慢慢來吧。

The Earth and the Moon are examples of celestial bodies with mass.

地球和月球就是具有品質的天體的例子。

The first one, of course, has more mass than the second.

當然，前者的品質大於後者。

Earth's mass distorts the space-time around it, but it also distorts the one around the Moon.

地球的品質扭曲了它周圍的時空，但同時也扭曲了月球周圍的時空。

This is the reason why the Moon orbits the Earth.

這就是月球繞地球運行的原因。

But the star that forms a black hole can be from dozens to billions of times larger than our Sun.

但形成黑洞的恆星可能比我們的太陽大幾十倍到幾十億倍。

Like we saw in the wooden table example, after it collapses, the star's mass will be compressed to a volume infinitely small and dense.

就像我們在木桌的例子中看到的那樣，恆星坍縮後，其品質將被壓縮到一個無限小、密度無限大的體積內。

Because of that, the distortion it will cause around it is so powerful that nothing will be able to escape its influence if it comes close enough.

正因為如此，它在周圍造成的扭曲會非常強大，只要它足夠靠近，任何東西都無法逃脫它的影響。

This point of no return is called the event horizon, a kind of boundary around a black hole that separates what's inside it from what's outside it.

這個 "不歸點 "被稱為事件穹界，是黑洞周圍的一種邊界，將黑洞內部和外部分隔開來。

When something crosses this limit, it cannot go back.

一旦越過這個界限，就無法回頭。

It gets disconnected from the universe, and we don't know what its final destination is.

它與宇宙斷開了聯繫，我們不知道它的最終目的地是哪裡。

What we do know is that once inside, everything moves toward the singularity, the center of the black hole.

我們所知道的是，一旦進入黑洞，所有的東西都會向奇點，也就是黑洞的中心移動。

And it's there that space and time as we know them cease to exist.

在那裡，我們所知的空間和時間都不復存在。

This is because, at that point, Einstein's equations don't work.

這是因為，在這一點上，愛因斯坦方程不起作用。

In fact, none of the laws of physics that we know so far work.

事實上，我們目前所知的物理定律沒有一條是有效的。

That is why some say that black holes, and more specifically, singularity, are the biggest unsolved problem in theoretical physics.

是以有人說，黑洞，更具體地說，奇點，是理論物理學中最大的未解難題。

It is where scientists have to admit that our knowledge of the universe has a limit.

科學家們不得不承認，我們對宇宙的瞭解是有限度的。