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Last week, the world lost one of the few science celebrities of the modern era: Stephen Hawking.
上周，世界失去了现代为数不多的几位科学巨匠之一：斯蒂芬·霍金。
He was a man who gave lectures to sold-out auditoriums, and he has the honor of being the only person to ever play himself on an episode of Star Trek.
霍金的讲座从来都是座无虚席，他还是唯一一位有幸在《星球大战》里饰演自己的人。
And Hawking's fame was not unfounded. He published papers for over 50 years!
霍金闻名世界是有充分原因的，50多年来，霍金一直不间断地发表论文。
He worked on a lot of problems in modern physics, from proposing what could have existed before the Big Bang, to hunting for an elusive theory of everything.
他研究了很多现代物理中的问题，从什么东西在大爆炸中消失，到寻找万事万物背后难以捉摸的理论。
But his most notable work was on black holes.
但他最为人所知的工作与黑洞有关。
In honor of one of the greatest legacies in cosmology, we wanted to celebrate and unpack some of his most famous findings.
为了向宇宙学中最伟大的财富之一致敬，我们想庆祝并讲解霍金最知名的一些发现成果。
First, in the 1960s, theoretical astrophysicists finally settled on black holes being a real thing.
首先，20世纪60年代的时候，一些搞理论的天体物理学家终于确定黑洞是真实存在的。
At the time, they believed that once a particle passed an event horizon, what we call the surface of a black hole, it could never come back.
那时候，这些天体物理学家认为，一旦某个粒子经过一片视界（今天的叫法是黑洞的表面），那么这个粒子就不会出来了。
These things were a one-way trip to ultimate obliteration.
这就是一趟单程的旅行，有去无回。
But in the 1970s, a handful of physicists started to question that, including Hawking.
但20世纪70年代的时候，有一些物理学家开始质疑这个观点，其中就包括霍金。
After building on previous ideas and doing lots of math, he eventually generated a startling conclusion: Black holes are not truly black.
在前人观点的基础上进行了大量的数学运算后，霍金最终得出了一个惊人的结论：黑洞并非真的是黑色的。
Surprise! Just when you think you know what's going on in the universe, Stephen Hawking comes along!
惊不惊喜！就当你以为自己对宇宙了如指掌时，霍金将你敲醒！
It turns out black holes emit a faint but steady stream of particles now called Hawking radiation.
其实，黑洞会放射出微弱但恒定的粒子束。现在，我们将这种粒子束成为霍金辐射。
And by proposing it, Hawking set the stage for some of the most important work currently happening in physics.
这个观点的提出让霍金为如今物理学最为重要的一些工作奠定了基础。
This radiation happens because quantum mechanics requires an intrinsic uncertainty to the universe.
之所以会发生霍金辐射是因为量子力学需要基本的不确定度。
The short explanation is that, even in so-called empty space,
简单点儿说，就是即便在看似空旷的宇宙里，
there are actually pairs of particles constantly popping into and out of existence over very small timespans.
其实也有许多成对儿的粒子在很短的时间里持续不断地进进出出。
We call them virtual particles. As long as these particles collide and annihilate one another, the laws of physics don't care.
我们称其为虚粒子，只要这些粒子保持碰撞以及吞并彼此的状态，那么物理定律就不会受到影响。
The energy is returned to space super duper quickly, so there's no net change in the universe.
能量返回宇宙的速度极快，所以宇宙不会有丝毫的变化。
Now, Hawking realized that if one of those pairs happens to form at the event horizon of a black hole, the object's extreme gravity could force them apart.
而霍金意识到：如果其中的一对粒子恰好在某个黑洞的视界上形成了，那么这对粒子由于受到极大的引力作用，就会相互分离。
That would give them enough energy to become real particles.
过程中，他们会获得足够大的能量，足以使他们变成实粒子。
Then, one could fall into the event horizon, while the other could fly away.
随后，其中一个粒子会掉落到视界中，而另一个粒子会飞走。
And those escaping particles are what we'd detect as Hawking radiation.
而这些逃逸的粒子就是我们所说的霍金辐射。
As they escaped, these particles would also carry away the energy the black hole gave them.
他们逃逸的过程中，会带走黑洞给予他们的能量。
And as a result, the hole would lose a tiny bit of mass. In other words, Hawking radiation causes black holes to evaporate.
所产生的结果就是，黑洞会损失一丢丢的质量，换言之，霍金辐射会导致黑洞蒸发。
We haven't actually detected this radiation yet, mostly because our technology just isn't good enough.
目前为止，我们还未曾观测到过霍金辐射，因为我们当前的技术还不够先进。
But it is required to work out the math, so we're pretty confident it's real.
但由于依然需要解数学题，所以我们十分坚信霍金辐射是确实存在的。
As a bonus, this phenomenon also sits at a critical juncture in astrophysics.
作为一种奖励，霍金辐射的现象依然处于天体物理学的关键位置上。
Because it involves both huge black holes and tiny particles, it connects the laws of general relativity and quantum physics.
因为霍金辐射涉及到巨大的黑洞和细小的粒子，所以就将广义相对论和量子物理学联系了起来。
These are the laws that respectively govern the very large and the very small.
而广义相对论和量子物理学分别与大小事物的规律有关。
These principles don't tend to play well together, and scientists have been trying to unite them for a while.
这两种理论无法较好地融合在一起，而很多科学家一直都在努力将他们放在一起考虑。
And if they can do that, they could create a theory of everything, a single model that could explain how the whole universe works.
如果有科学家能做到这一点，就能创造出一个普世于万事万物的理论，一个可以解释整个宇宙运转机制的单个模型。
So by proposing this radiation's existence, Stephen Hawking laid the foundation for the progress that's been made on that theory in recent years.
所以，通过提出霍金辐射的存在，霍金为近年来以该理论为基础所取得的成果奠定了基础。
Of course, black hole evaporation also presents us with a bit of a physics problem, which we've mentioned on SciShow Space before.
当然了，黑洞蒸发也向我们提出了一个相关的物理学问题，这个问题我们在之前的节目里有提到过。
Separately, both general relativity and quantum mechanics predict that the present time period preserves information about the past.
不过，广义相对论和量子力学都预测了一点，那就是：现在会保留过去的信息。
And that makes sense. After all, we usually think about causes happening before effects.
这一点说得通，毕竟，我们总是会去想发生于结果之前的原因。
But no matter what sorts of particles fall into a black hole, the outgoing Hawking radiation is always the same.
但无论是哪种粒子掉落在了黑洞里，霍金辐射都适用。
The black hole seems to lack all information of what you threw in there, which doesn't make sense.
但黑洞上似乎并没有出现掉落在里面的东西，这一点就说不通了。
This is called the Black Hole Information Paradox. And Hawking and other physicists have attempted to resolve it over the decades.
这就是黑洞信息悖论，几十年来，霍金等物理学家一直在试图解决这个问题。
Back in the 1990s, Hawking and fellow physicist friend Kip Thorne even made a wager about the answer, which was pretty common for Hawking.
上世纪90年代的时候，霍金以及他的一位同为物理学家的朋友基普·索恩甚至就问题的答案打了赌。打赌是霍金常做的事情。
They bet Thorne's colleague John Preskill that the math would eventually prove that the information that falls into a black hole is indeed lost forever.
他们跟索恩的同事约翰·普雷斯基尔打的赌是：人类最终可以通过数学手段证明，掉落在黑洞中的信息确实永远消失了。
Unfortunately, despite lots of work, there's no definitive answer yet.
不幸的是，虽然做了大量的工作，但还是没有肯定的结果。
Hawking did concede in 2004, but many physicists argue the puzzle isn't really solved.
2004年，霍金确实松口让步了，但还是有很多物理学家认为这个谜题依然没有解开。
Still, this doesn't make the discovery of Hawking radiation any less significant, it just means there's always more to know.
不过，这丝毫不会影响霍金辐射发现的重要性，这只是表明，还有很多东西有待探索。
Another one of Hawking's major ideas, which he proposed in 1971, was the existence of black holes that did not form from collapsing stars.
1971年，霍金提出了另一个主要观点，那就是：黑洞并不是由恒星坍缩形成的。
Instead, he suggested that they formed within the very first second of the universe, thanks to the density of energy fluctuating as space expanded and cooled.
相反，他认为，黑洞在宇宙形成之时就有了，这是因为宇宙在扩张和冷却期间不断波动的能量密度。
Because they didn't come from stars, these so-called primordial black holes would supposedly have a wide range of possible masses.
由于黑洞并不是由恒星形成的，所以这些所谓的原始黑洞可能质量各不相同。
They could be anywhere from one ten-thousandth of a gram, the smallest they could possibly be according to physics as we know it,
根据我们当前的物理学，黑洞的质量最小可能只有0.01克，
to thousands of times the mass of the Sun. Hawking said the really tiny ones would have evaporated a long time ago,
最大可能达到太阳的数千倍，霍金表示，质量特别小的黑洞可能在很久以前就蒸发掉了，
but those with a mass around 10 trillion kilograms would just be ending their lives now.
而质量达近10万亿千克的黑洞可能也快蒸发掉了。
As the mass of these black holes approaches zero, they should experience runaway evaporation.
随着黑洞的质量趋近于零，就会经历蒸发。
That would create a massive burst of radiation equivalent to millions of one-megaton hydrogen bombs.
其迸发出的巨大辐射与数百万个一兆吨氢弹的能量差不多。
And those explosions could, hypothetically, be detected by instruments like NASA's Fermi Telescope.
我们假设这种爆炸可以被美国宇航局的费米伽玛射线空间望远镜探测到。
Hawking suggested that several primordial black holes could even lie hiding in the Milky Way's halo.
霍金认为，可能还有一些原始的黑洞藏在银河系的光晕里。
And other astrophysicists have identified them as a possible candidate for the mysterious stuff we currently call dark matter.
还有一些天体物理学家认为黑洞可能会变成我们现在所称的暗物质。
So it could turn out that Hawking was responsible for proposing what dark matter really is.
而最终可能又要通过霍金的著作来解释暗物质的真正含义。
But only time will tell. As we keep building off Hawking's work,
但只有时间才能告诉我们这一切，我们现在依然在霍金的研究成果上继续探索，
there's a chance he could still get his name somewhere else in the astrophysics textbooks.
所以霍金的名字还是可能会出现在天体物理学教科书里。
But no matter if that happens or not, it's clear that the thoughts Stephen Hawking had and the work he contributed will resonate with people,
但无论是否如此，很明显的一点是：霍金曾有过的想法和贡献过的成果都会在人们之间引起共鸣，
and not just scientists, for generations to come. Besides being a brilliant physicist, he was also a powerful advocate for science,
不只是科学家，而是后辈的子孙，除了是一名杰出的物理学家之外，霍金还极力推崇科学，
and a lot more people are in love with the universe because of what he did.
很多人之所以对宇宙感兴趣，就是因为霍金所做的工作。
So thanks, Stephen Hawking. Thanks to you, we'll remember to look up at the stars and not down at our feet.
所以，在此，我们还是要深深地感谢霍金，正是因为您，我们才会记得不只要脚踏土地，也要仰望星空。
And thank you, for watching. If you're looking for a tangible way to celebrate your love of the universe, please check out SciShowFinds.com.
感谢大家收看本期的《太空科学秀》，如果大家还在寻找欢庆对宇宙热爱之情的有效方法，就登录SciShowFinds.com吧。
This is a little corner store of the internet that Hank and the team set up
这虽然只是汉克及其团队在互联网上建立起的冰山一角，
so that we could share physical things that remind us how much we love science and care about the universe.
但在这里，我们可以分享物理方面的知识，提醒我们对科学和宇宙的热爱之情。
One of the items that I picked out is the PocketLab which lets you gather data and do experiments wherever you are.
我尤其要推荐《口袋实验室》，在这里，大家不只可以不分地点地收集数据，还能做实验。
And I just got my bee heart pin, so I'm hoping to run into people out in the world with the same pin and we can talk about mason bees,
我刚刚得到了属于自己的蜜蜂心形别针，所以我希望某天我在大街上碰到跟我带着同样别针的人，这样我们就能畅谈石蜂、
and pollination, and colony collapse! Another of my favorite finds too, are the Climb Mars socks with Olympus Mons on them.
授粉、蜂群崩坏症候群这样的问题，我还要推荐《可以攀登火星奥林匹斯山的袜子》。
My plan is to wear them when I'm not feeling as adventurous as I want to, so if I do forget and start looking down at my feet,
我打算在自己遗失冒险精神的时候穿上这双袜子，这样的话，在我确实忘记了探索，并开始低头看脚的时候，
they'll remind me to look up at the stars and remember Stephen Hawking.
这双袜子可以提醒我仰望星空，想想斯蒂芬·霍金。
