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We're here at the University of California, Santa Barbara to discuss a dream of humanity:
这里是利福尼亚大学圣巴巴拉分校，接下来，我们会共同讨论一个全人类的梦想：
the ability to exit our solar system and enter another solar system.
离开我们的太阳系，进入另一个太阳系。
And the solution is literally before your eyes.
解决方案实际上就在我们的眼前。
So I have two things on me that you have -- I have a watch, and I have a flashlight, which, if it's not on you, it's on your phone.
我身上有两件东西，你们也有：一块手表和一个手电筒，至少在你们的手机上都可以找到。
So the watch keeps time, and my flashlight just illuminates my environment.
手表用来查看时间，手电筒则可以照亮我周围的环境。
So like art, to me, science is illuminating. I want to see reality in a different way.
就像艺术一样，对我而言，科学就是一盏明灯。我想以不同的方式看待现实。
When I turn on the flashlight, suddenly the dark becomes bright, and I suddenly see.
当我打开手电筒时，周围立刻就变得明亮起来，视野也开阔了。
The flashlight and its light, which you can see coming out -- the light on my hand is not only illuminating my hand, it's actually pushing on my hand.
你可以看到，手电筒发出的光--我手上的光不仅照亮了我的手，它实际上也推动着我的手。
Light carries energy and momentum.
光伴随着能量和动量。
So the answer is not to make a spacecraft out of a flashlight,
所以答案并不是要用手电筒制作宇宙飞船，
by having the exhaust come out this way and the spacecraft goes that way -- that's what we do today with chemistry.
而是要让光以这种方式产生推力，而航天器以这种方式移动--就是我们今天用化学燃料所实现的。
The answer is this: Take the flashlight and put it somewhere on the Earth, in orbit or on the Moon,
答案是这样的：将手电筒放在地球上的某个地方，在轨道或月球上，
and then shine it on a reflector, which propels the reflector to speeds which can approach the speed of light.
然后将其照射在反射器上，从而推动反射器，让其能够以接近光速移动。
Well, how do you make a flashlight that's big enough?
那么问题来了，如何做出足够大的手电筒？
This isn't going to do it, my hand doesn't seem to be going anywhere.
很明显，我手里的手电筒起不到什么效果，我的手也没有感受到任何推力。
And that's because the force is very, very low.
那是因为这股力量非常非常小。
So the way that you can solve this problem is taking many, many flashlights, which are actually lasers, and synchronizing them in time,
那么解决此问题的方法就是，采用许多激光手电筒，并及时进行同步，
and when you gang them all together into a gigantic array, which we call a phased array,
当将它们组合成一个巨大的阵列，我们称之为“相控阵”，
you then have a sufficiently powerful system, which, if you make it roughly the size of a city,
于是就有了一个足够强大的系统，如果把它做成一个城市的大小，
it can push a spacecraft, which is roughly the size of your hand, to speeds which are roughly 25 percent the speed of light.
它就可以将一个手掌大小的航天器以大约25%的光速推向天空。
That would enable us to get to the nearest star, Proxima Centauri, which is a little over four light years away, in less than 20 years.
这将使我们能够在不到20年的时间内到达离我们只有4光年多一点的最近的恒星，比邻星。
Initial probes would be roughly the size of your hand, and the size of the reflector that you're going to use is going to be roughly human size,
最初的探针大约是手掌的大小，而所使用的反射器大约是一个人的大小，
so not a whole lot larger than myself, but a few meters in size.
所以不会比我大很多，大概几米。
It only uses the reflection of light from this very large laser array to propel the spacecraft.
它仅使用来自这个非常大的激光器阵列所反射的光来推动航天器。
So let's talk about this. This is a lot like sailing on the ocean.
打个比方，这就像在海上航行。
When you sail on the ocean, you're pushed by the wind. And the wind then drives the sail forward through the water.
当我们在海上航行时，会被风推动着前进。然后风推动帆在水中前进。
In our case, we're creating an artificial wind in space from this laser array,
在我们的例子中，我们是在通过激光器阵列，在空间中创建人造风，
except the wind is actually the photons from the laser itself, the light from the laser becomes the wind upon which we sail.
只不过这里的“风”实际上是激光器本身的光子，来自激光器的光变成了吹动船帆的风。
It is a very directed light -- it's often called directed energy.
它是定向性非常好的光--通常被称为“定向能量”。
So why is this possible today, why can we talk about going to the stars today,
那么，为什么今天这一切成为了可能呢？为什么我们在今天可以讨论太空旅行了呢？
when 60 years ago, when the space program began in earnest, people would have said, "That's not possible"?
然而60年前，当太空计划刚启动时，人们会说：“那不可能。”
Well, the reason it's possible today has a lot to do with the consumer, and the very fact that you're watching me.
然而今天，这一切之所以成为了可能，与消费者有着很大的关系，具体来说，就是你们观看视频的行为。
You're watching me over a high-speed internet, which is dominated by the photonics of sending data over fiber optics.
你们正通过高速互联网收看这段视频，这项技术是由通过光纤传输数据的光子学主导的。
Photonics essentially allow the internet to exist in the way it does today.
从本质上说，有了光子学，今天的互联网才得以存在。
The ability to send vast amounts of data very quickly is the same technology that we're going to use to send spacecraft very quickly to the stars.
快速发送大量数据的能力，与我们将要用来将航天器快速发射到恒星的技术大同小异。
You effectively have an infinite supply of propellent, you can turn it on and off as needed.
你们实际上已经拥有了无限量的推进剂，可以根据需要开启和关闭。
You do not leave the laser array that produces the light on for the entire journey.
我们不会在整个行程中都让激光阵列保持开启的状态。
For small spacecraft, it's only on for a few minutes, and then it's like shooting a gun.
对于小型航天器，只需要开启几分钟，就能如同开枪一般把航天器发射出去。
You have a projectile which just moves ballistically.
航天器会按照预定轨道飞行。
Even if we, as humans, are not on the spacecraft, at least we have the ability to send out such spacecraft.
即使人类不在太空飞船上，至少我们也有能力发射这种太空飞船。
You want to remotely view, or have remote imaging and remote sensing, of an object.
我们可以对一个对象进行远程监控，或远程成像和遥感。
So when we go to Jupiter, for example, with a flyby mission,
那么，假如当我们带着飞行任务前往木星时，
we are taking pictures of Jupiter, we're measuring the magnetic field, the particle density, and we're basically exploring remotely.
我们可以为木星拍照，测量磁场和粒子密度，基本上都是在进行远程探索。
The same way that you are looking at me. And all of the current missions that are beyond the Moon are remote-sensing missions.
这就跟你们在线观看这个视频一样。目前，除月球以外的所有任务都是遥感任务。
What would we hope to find if we visited an exoplanet?
如果我们拜访了系外行星，我们希望找到什么？
Perhaps there's life on an exoplanet,
也许系外行星上会有生命，
and we would be able to see evidence of life, either through atmospheric biosignatures or through, you know, a dramatic picture,
我们将能够通过大气生物特征或动态的画面观察到生命存在的证据，
we would be able to see something actually on the surface.
我们将能够看到星球表面的情况。
We don't know if there's life elsewhere in the universe.
我们不知道宇宙中是否还有其他生命。
Perhaps on the missions that we send out, we will find evidence for life, perhaps we will not.
也许在我们执行的任务中，我们会找到生命的证据，也许不会。
And while economics may seem like an inappropriate thing to bring into a talk on interstellar capability,
尽管把经济学理论应用在星际探索能力方面有些不妥，
it is in fact one of the driving issues in achieving interstellar capability.
但实际上，这是实现星际探索能力的驱动因素之一。
You have to get things to the point where they're economically affordable to do what we want to do.
我们必须在经济可以承受的范围内去做我们想做的事。
So currently, we have systems in the lab which have achieved the ability to synchronize over very large scales,
现在，我们实验室中的系统已经实现了大空间内的同步能力，
out to about 10 kilometers or roughly six miles.
能够达到大约10公里或6英里的空间范围。
We've been able to achieve synchronization of laser systems, and it's worked beautifully.
我们已经能够实现激光系统的同步，并且效果很好。
We've known how to build lasers for many decades, but it's only now that the technology has gotten inexpensive enough,
我们几十年前就已经知道如何制造激光器了，但是现在这项技术已经变得足够便宜，
and become mature enough that we can imagine having huge arrays, literally, kilometer-scale arrays,
并且足够成熟，让我们得以想象如何构建巨大的、可以达到公里规模的阵列，
much like solar farms, but instead of receiving light, they transmit light.
就像太阳能电站一样，但是不会接收光，只会透射光。
The beauty of this type of technology is it enables many applications, not just relativistic flight for small spacecraft,
这种技术的优点在于它可以实现许多应用，不仅适用于小型航天器的相对论飞行，
but enables high-speed spacecraft, high-speed flight in our solar system, it enables planetary defense, it enables space debris removal,
还可以支持高速航天器在太阳系中的高速飞行，实现行星防御、空间碎片清除，
it enables powering of distant assets that we may want to send power to, such as spacecraft or bases on the Moon or other places.
还可以为我们的远距离资产提供电力，例如月球或其他地方的航天器和基地。
It's an extremely versatile technology, it's something that humanity would want to develop even if they didn't want to send spacecraft to the stars,
这是一项极为灵活的技术，也是人类想要研发的东西，即使人类并不想将航天器送入星际空间，
because that technology allows so many applications that are currently not feasible.
因为该技术能够许多目前不可行的应用变成现实。
And therefore, I feel it's an inevitable technology, because we have the ability, we just need to fine-tune the technology and in a sense,
因此，我认为这是一种不可避免的技术，因为我们有能力，只需要对技术进行微调，并且在某种意义上，
wait for economics to catch up with us so that it becomes cheap enough to build the large systems.
等经济变得更发达，成本降低到足以构建大型系统。
The smaller systems are affordable now. And we've already started building prototype systems in our lab.
目前，小型系统的造价还是可以承受的。而且我们已经开始在实验室中构建原型系统。
So while it's not going to happen tomorrow, we've already begun the process, and so far, it's looking good.
因此，尽管现在还不能做到一觉醒来，美梦成真，但我们已经迈出了第一步，到目前为止，进展还算顺利。
This is both a revolutionary program, in terms of being a transformative technology, but it's also an evolutionary program.
就变革性技术而言，这既是一个革命性的项目，也是一个有进化意义的项目。
So personally, I do not expect to be around when the first relativistic flight happens.
就我个人而言，我不认为此生能有幸看到第一次相对论飞行实现的那一天。
I think that's probably 30-plus years off before we get to that point, and perhaps more.
我认为距达到这一目标可能还要30多年的时间，甚至更久。
But what inspires me is to look at the ability to achieve the final goal.
但让我备受鼓舞的是可以预见能够达到最终目标的能力。
Even if it does not happen in my lifetime, it can happen in the lifetime of the next generation or the generation beyond that.
就算我这代人赶不上那一天，下一代人也会见证那一刻，或者再往后的一代人。
The consequences are so transformative that we literally, in my opinion, must go down this path,
这种成果具有极其深远的变革意义，在我看来，我们必须沿着这条路走下去，
and must explore what the limitations are, and then how do we overcome the limitations.
必须探索局限性是什么，然后如何克服这些局限性。
The search for life on other planets would be one of humanity's foremost explorations,
在其他星球上寻找生命将是人类最重要的探索之一，
and if we're able to do so, and actually find life on another planet, it would change humanity forever.
如果我们能够做到，并且的确在另一个星球上找到了生命，就将永远改变人类。
Everything is profound in life. If you look deep enough, you'll find something incredibly complex and interesting and beautiful in life.
生命中的每一件事都有其深刻的意义。如果你观察得足够深入，就会发现生活中令人难以置信的复杂、有趣和美丽的事物。
And the same is true with the lowly photon that we use to see every day.
我们每天接触到的微小的光子也是如此。
But when we look outside and we imagine something vastly greater, an array of lasers that are synchronized,
但是当我们把目光投向外太空，同时想象一番更广阔的天地，一个同步的激光阵列，
we could imagine things which are just extraordinary in life.
我们就可以想象到生活中那些非同寻常的事物。
And the ability to go to another star is one of those extraordinary capabilities.
而去往另一颗星球的能力，就是这种非凡的能力之一。
