(单词翻译:单击)
Do you think you could you make a black hole out of light?
你想过可以用光制造黑洞吗？
That might sound like a trick question, or like something right out of the "showerthoughts" subreddit.
这听起来像是一个恶作剧，或是reddit子网站上的“淋浴灵感”。
But physicists say that it should be possible to create a black hole out of nothing but light,
但是物理学家们说，用光创造黑洞是可能的，
called a kugelblitz, after the German word for "ball lightning".
创造出来的东西用德语叫做球形闪电。
Even though they have no idea what would actually happen if you tried to do it.
即使他们也不知道如果你尝试了会发生什么。
Before we talk about that though, let's talk about the more standard black holes.
在我们讨论这个想法之前，先说说标准黑洞。
Usually, a black hole forms when a lot of matter is packed into very little space,
通常，许多物质被挤到很小的空间时，就会形成黑洞，
which increases its density.
从而增加了它的密度。
If the matter is dense enough, the gravity at its surface becomes so strong
如果物质密度足够大的话，它表面的引力就会变得非常强，
that nothing, not even light, can escape its clutches.
以至于没有东西，甚至是光都逃不过它的拉扯。
So to make the Earth into a black hole,
所以要把地球变成黑洞的话，
you would have to compress its 6 trillion trillion kilograms of rock and water and metal
你就得将它6*10^24公斤的岩石、水和金属
down into a sphere with a diameter of just 16 millimeters.
压缩成直径只有16毫米的球体。
That's how dense I'm talking about. But we're just getting started here.
这就是我说的密度。但我们才刚开始。
Einstein taught us that E=mc^2.
爱因斯坦教会我们E=mc^2，
In other words, that the energy stored in a bit of matter is equal to its mass times the speed of light squared.
换句话说，物质中储存的能量等于它的质量乘以光速的平方。
This means that there are huge amounts of energy in tiny bits of matter, like atoms,
这意味着微小物质中含有大量的能量，比如原子，
which is the basic idea behind nuclear power and nuclear weapons.
它是核能和核武器背后的基本原理。
It also means that energy can sometimes act like matter.
同时也意味着能量有时可以充当物质。
Now, light doesn't have any mass, but it does have energy.
光有能量，没质量。
And, thanks to E=mc^2, gravity can't tell the difference between energy and matter, and pulls on them both.
由于E = mc^2公式，引力不能区分能量和物质，两者都能牵引。
And this raises an interesting possibility.
这就提出了一个有趣的可能性。
All it takes to make a black hole is to pack a bunch of matter in one place,
制造黑洞所需的一切就是把一堆物质放在一个地方，
and gravity treats light just like it treats matter.
而引力对待光就像对待物质一样。
So you could theoretically make a black hole out of nothing but light, a kugelblitz.
所以理论上，你可以用光制造黑洞，即球形闪电。
Creating a kugelblitz would take a really, really incredible amount of light, though,
不过，制造球形闪电需要的光数量非常非常惊人，
because now we're working with Einstein's famous equation in the opposite direction.
因为我们正反向应用爱因斯坦的著名质能等式。
Before, we had a tiny amount of matter producing a huge amount of energy.
之前，我们有少量物质就能产生许多能量。
Now, we have to supply a ton of energy, in the form of light, for it to act like tiny bits of matter.
现在我们必须用光的形式供应大量的能量，因为它的作用就像微小物质。
So let's go back to that hypothetical black hole with the mass of the Earth.
让我们回到那个有着地球质量的假设黑洞上。
If we wanted to make that same black hole out of light, how much light would would we need?
如果我们用光制造同样的黑洞，需要多少光呢？
All of the lights on Earth? All of the sunlight that hits the Earth in a day? In a year?
地球上的所有光？一天射到地球上的太阳光？或是一年射到地球上的光？
What about all of the sunlight put out by the sun over the course of an entire year? Not even close.
那么，太阳一整年发出的光呢？还差得远呢。
To get an Earth-mass kugelblitz,
要想制造地球质量的球形闪电，
we would need all of the light put out over 10 years by all of the stars within 350 light-years of Earth,
我们需要地球350光年范围内所有恒星发出的光
all squished into a bit of space the size of a mosquito.
全部压缩在蚊子大小的空间内。
Okay, that's a lot of light.
好吧，它需要很多光。
But what if we wanted to make a black hole that was way, way smaller?
但如果我们想制造一个小点儿的黑洞呢？
Like, I don't know... the mass of a big cruise ship, like the Titanic ... about 50 million kilograms?
比如，我不知道...有一艘大型游轮比如泰坦尼克号那么重，大约5000万公斤的黑洞呢？
To make a kugelblitz that small,
要制造一个小黑洞，
you'd need to squeeze all of the sunlight that hit Earth last year into a volume 8,000 times smaller than a proton.
你需要把去年射到地球的所有阳光压缩成质子体积8千分之一的物体。
It's hard to even imagine how so much light could get shoved into one place,
我们很难想象这么多的光如何挤到一个地方，
or any sort of technology that could accomplish even a fraction of that in the foreseeable future.
或者任何一种技术在可预见的未来能做到这一点。
But even if it could happen, there's another problem:
但即使能做到，还有另一个问题：
Making a kugelblitz means that you have to pump so much light-energy into such a tiny region of space that it would get really hot,
制造一个球形闪电意味着你必须把非常多的光能量注入到一个小空间内，它会变得非常热，
since heat is just a form of energy.
因为热量是能量的一种形式。
We are talking hotter than the universe was a hundredth of a millionth of a trillionth of a trillionth of a trillionth of a second after the Big Bang.
我们说的是它比宇宙大爆炸后10^-40秒的宇宙还热。
And at that extreme temperature, physics as we know it just sort of stops working:
在这种极端温度下，我们知道物理会停止工作。
space turns soupy, gravity is nonsense, and we have no idea how to describe anything.
空间像汤一样，引力无意义，万物难以言表。
So if space gets that hot, gravity might go haywire and not be able to form black holes at all any more.
因此如果空间变得非常热，引力可能会失控，再也无法形成黑洞了。
Or maybe gravity would get super strong and form a black hole with a million times less energy than we think it should take right now.
或者引力变得非常强，用比我们想象中少百万倍的能量形成一个黑洞。
We just don't know, we might never know.
我们不知道，可能永远也不会知道。
For now, it seems like kugelblitzes might be theoretically possible, based on Einstein's basic equations relating energy and mass.
目前看来，基于爱因斯坦的质能方程，球形闪电似乎在理论上是可能的。
It's a cool idea: using lots of highly focused light to create a black hole, something that even light can't escape from.
这是一个很棒的主意：用许多高度聚焦的光创造一个光都逃脱不了的黑洞。
But we have no idea how we, or the universe would make one,
但我们不知道自己如何或宇宙会怎样制造黑洞，
or even if there's some undiscovered law of nature that forbids it from existing.
或者有一些未被发现的自然法则禁止它的存在。
Thanks for watching this episode of SciShow Space,
感谢您收看本期的太空科学秀，
and thanks especially to our patrons on Patreon who let us talk about these weird things,
特别感谢Patreon对本节目的大力支持，让我们能够谈论这些奇怪的事物，
thank you so much for that.
非常感谢你们。
If you want to help us keep making episodes like this,
如果你想帮助我们继续制作此类节目，
you can go to patreon.com/scishow to learn more.
就登陆patreon.com/scishow了解更多信息吧。
And don't forget to go to youtube.com/scishowspace and subscribe!
也不要忘了登录youtube.com/scishowspace点击订阅哦！
