TED2018
Stephen Webb: Where are all the aliens?
斯蒂芬 · 韦伯: 外星人在哪里？
Filmed:
Readability: 5
5,111,570 views
宇宙非常古老，大得不可思议，并且有数万亿颗行星——那么外星人都在哪里呢？天文学家斯蒂芬 · 韦伯对此有一个解释：我们在宇宙中是独一无二的。在这个让人大开眼界的演讲中，他讲述了一颗行星为了容纳外星文明而需要清除的巨大障碍——并且说明了我们可能是宇宙中绝无仅有的美丽之处。 “宇宙的沉默是在呐喊：'我们是幸运的生物'。”韦伯说。
Stephen Webb - Writer, scientist
Stephen Webb is a science fiction fan who's passionately interested in what the future might hold for our species. Full bio
Stephen Webb is a science fiction fan who's passionately interested in what the future might hold for our species. Full bio
Double-click the English transcript below to play the video.
00:13
I saw a UFO once.
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我见过一次不明飞行物。
那时我八、九岁，
00:15
I was eight or nine,
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和一个比我大几岁的朋友在街上玩，
00:17
playing in the street with a friend
who was a couple of years older,
who was a couple of years older,
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我们发现一个普通的
银色碟子在上空盘旋。
银色碟子在上空盘旋。
00:20
and we saw a featureless silver disc
hovering over the houses.
hovering over the houses.
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我们盯着它看了几秒钟，
00:25
We watched it for a few seconds,
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然后它飞走了，速度极快。
00:27
and then it shot away incredibly quickly.
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虽然我只是个小孩，
00:30
Even as a kid,
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但我依然感到气愤，
因为它不符合物理规律。
因为它不符合物理规律。
00:31
I got angry it was ignoring
the laws of physics.
the laws of physics.
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00:35
We ran inside to tell the grown-ups,
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我们跑回家告诉大人们，
但他们表示很怀疑——
00:37
and they were skeptical --
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00:39
you'd be skeptical too, right?
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谁都会怀疑的，对吧？
00:42
I got my own back a few years later:
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几年后，我扳回一局：
那些大人中的一个对我说，
00:43
one of those grown-ups told me,
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“昨晚我看到一个飞碟，
00:45
"Last night I saw a flying saucer.
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我当时刚在酒吧喝了几杯出来。”
00:47
I was coming out of the pub
after a few drinks."
after a few drinks."
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我当时就打断他说，
“我可以解释你看到的是什么。”
“我可以解释你看到的是什么。”
00:49
I stopped him there.
I said, "I can explain that sighting."
I said, "I can explain that sighting."
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（笑声）
00:52
(Laughter)
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心理学家已经证明，
我们不能相信自己的大脑
我们不能相信自己的大脑
00:53
Psychologists have shown
we can't trust our brains
we can't trust our brains
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00:56
to tell the truth.
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说的都是事实。
00:57
It's easy to fool ourselves.
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我们很容易被自己欺骗。
我看到了某种东西，
00:59
I saw something,
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但哪种情况可能性更大——
01:01
but what's more likely --
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我看到的是外星飞船？
01:02
that I saw an alien spacecraft,
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01:04
or that my brain misinterpreted
the data my eyes were giving it?
the data my eyes were giving it?
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还是我的大脑误解了眼睛传给它的数据？
01:10
Ever since though I've wondered:
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从那以后，我一直在想：
为什么我们在周围看不到飞碟呢?
01:11
Why don't we see
flying saucers flitting around?
flying saucers flitting around?
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至少，
01:14
At the very least,
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我们为什么看不到
宇宙中的其它生命呢?
宇宙中的其它生命呢?
01:16
why don't we see life
out there in the cosmos?
out there in the cosmos?
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这是一个谜，
01:18
It's a puzzle,
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过去的三十年里，我与不同领域的
01:20
and I've discussed it
with dozens of experts
with dozens of experts
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数十位专家讨论过这个问题。
01:22
from different disciplines
over the past three decades.
over the past three decades.
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我们并没有达成共识。
01:25
And there's no consensus.
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弗兰克 · 德雷克从1960年
开始寻找外星信号——
开始寻找外星信号——
01:27
Frank Drake began searching
for alien signals back in 1960 --
for alien signals back in 1960 --
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到目前为止，什么都没找到。
01:32
so far, nothing.
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一年又一年，
01:34
And with each passing year,
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什么也观测不到，
01:35
this nonobservation,
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没有任何外星活动的证据，
这越来越让人困惑，
这越来越让人困惑，
01:37
this lack of evidence
for any alien activity gets more puzzling
for any alien activity gets more puzzling
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因为我们应该能看到它们的，不是吗?
01:42
because we should see them, shouldn't we?
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01:47
The universe is 13.8 billion years old,
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宇宙已经存在了大概
138亿年了。
01:50
give or take.
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如果我们用一年来代表宇宙的年龄，
01:52
If we represent the age
of the universe by one year,
of the universe by one year,
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那么我们这个物种形成于
01:55
then our species came into being
about 12 minutes before midnight,
about 12 minutes before midnight,
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12月31日午夜前的12分钟。
02:00
31st December.
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02:02
Western civilization
has existed for a few seconds.
has existed for a few seconds.
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西方文明刚出现几秒钟。
而外星文明可能是夏季开始的。
02:05
Extraterrestrial civilizations
could have started in the summer months.
could have started in the summer months.
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02:10
Imagine a summer civilization
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想象一个夏季出现的文明
开发出比我们更先进的技术，
02:13
developing a level of technology
more advanced than ours,
more advanced than ours,
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但我是说符合公认的
物理理论的技术，
物理理论的技术，
02:17
but tech based on accepted physics though,
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而不是虫洞或曲速引擎
——那种类型的——
——那种类型的——
02:19
I'm not talking wormholes
or warp drives -- whatever --
or warp drives -- whatever --
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我只说像TED在这儿庆祝的
那种技术的进步。
那种技术的进步。
02:23
just an extrapolation
of the sort of tech that TED celebrates.
of the sort of tech that TED celebrates.
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02:28
That civilization could program
self-replicating probes
self-replicating probes
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这个文明也许会编写
可自我复制的探测器，
可自我复制的探测器，
去访问银河系中的每一个星系。
02:32
to visit every planetary
system in the galaxy.
system in the galaxy.
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02:35
If they launched the first probes
just after midnight one August day,
just after midnight one August day,
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如果他们在8月的某天午夜，
发射了第一颗探测器，
发射了第一颗探测器，
02:41
then before breakfast same day,
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那么在当天早餐之前，
他们可能就已经统治银河系了。
02:43
they could have colonized the galaxy.
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02:46
Intergalactic colonization
isn't much more difficult,
isn't much more difficult,
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银河系之外的星际统治也不算太难，
只是要多花点时间而已。
02:49
it just takes longer.
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02:51
A civilization from any one
of millions of galaxies
of millions of galaxies
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在数百万星系中，
任何一个星系的文明
任何一个星系的文明
都有可能统治我们的银河系。
02:54
could have colonized our galaxy.
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02:56
Seems far-fetched?
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听起来很牵强?
也许是的，
02:58
Maybe it is,
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但外星人难道就不做一些
可以被探测到的活动吗？
可以被探测到的活动吗？
02:59
but wouldn't aliens engage
in some recognizable activity --
in some recognizable activity --
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比如在恒星周围造个小世界获取阳光，
03:05
put worldlets around a star
to capture free sunlight,
to capture free sunlight,
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合作一个星际维基百科，
03:09
collaborate on a Wikipedia Galactica,
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或者只是对着宇宙大喊：
“我们在这里！”
“我们在这里！”
03:12
or just shout out
to the universe, "We're here"?
to the universe, "We're here"?
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03:16
So where is everybody?
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那么他们到底在哪儿?
03:18
It's a puzzle because we do expect
these civilizations to exist, don't we?
these civilizations to exist, don't we?
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这是个谜，因为我们确实认为
有这种文明存在，不是吗?
有这种文明存在，不是吗?
毕竟，银河系中可能有
一万亿颗星球——
一万亿颗星球——
03:24
After all, there could be
a trillion planets in the galaxy --
a trillion planets in the galaxy --
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也许更多。
03:27
maybe more.
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03:29
You don't need any special knowledge
to consider this question,
to consider this question,
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你不需要任何专业知识
来思考这个问题，
来思考这个问题，
多年来，我和很多人
都探讨过这个问题。
都探讨过这个问题。
03:34
and I've explored it
with lots of people over the years.
with lots of people over the years.
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我发现他们对这个问题的
思考有个标准，
思考有个标准，
03:37
And I've found they often
frame their thinking
frame their thinking
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03:40
in terms of the barriers
that would need to be cleared
that would need to be cleared
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就是如果一个星球要
承载可交流的文明，
承载可交流的文明，
03:44
if a planet is to host
a communicative civilization.
a communicative civilization.
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它需要清除一些障碍。
03:49
And they usually identify
four key barriers.
four key barriers.
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他们通常会考虑四个关键障碍。
宜居性——
03:52
Habitability --
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这是第一个障碍。
03:54
that's the first barrier.
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我们需要一颗刚好位于
“适居带”中的陆地行星，
“适居带”中的陆地行星，
03:55
We need a terrestrial planet
in that just right "Goldilocks zone,"
in that just right "Goldilocks zone,"
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04:00
where water flows as a liquid.
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上面的水以液态形式流动。
04:03
They're out there.
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这样的星球是存在的。
04:04
In 2016, astronomers confirmed
there's a planet in the habitable zone
there's a planet in the habitable zone
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2016年，天文学家证实，
有一颗行星位于最近的恒星的
有一颗行星位于最近的恒星的
04:09
of the closest star,
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适居带中，
接近于半人马座——
04:10
Proxima Centauri --
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非常近，所以“突破摄星”工程
计划发送一个探测器过去。
计划发送一个探测器过去。
04:12
so close that Breakthrough Starshot
project plans to send probes there.
project plans to send probes there.
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我们已经成为
可以穿越星际的物种了。
可以穿越星际的物种了。
04:17
We'd become a starfaring species.
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04:21
But not all worlds are habitable.
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但不是所有的星球都适合居住。
有些离恒星太近，会被烤焦，
04:23
Some will be too close to a star
and they'll fry,
and they'll fry,
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有些离得太远，会被冻结。
04:25
some will be too far away
and they'll freeze.
and they'll freeze.
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04:28
Abiogenesis --
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生命起源——
从非生命中孕育出生命——
04:30
the creation of life from nonlife --
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这是第二个障碍。
04:31
that's the second barrier.
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04:34
The basic building blocks of life
aren't unique to Earth:
aren't unique to Earth:
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构成生命的基本要素并非地球独有：
彗星上已经发现了氨基酸，
04:37
amino acids have been found in comets,
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在星际尘埃云中的复杂有机分子，
04:40
complex organic molecules
in interstellar dust clouds,
in interstellar dust clouds,
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在外层空间发现了水。
04:43
water in exoplanetary systems.
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04:47
The ingredients are there,
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那些成分都是存在的，
我们只是不知道
它们如何结合起来创造生命，
它们如何结合起来创造生命，
04:48
we just don't know
how they combine to create life,
how they combine to create life,
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而且可能在一些世界里，
生命还没有诞生。
生命还没有诞生。
04:51
and presumably there will be worlds
on which life doesn't start.
on which life doesn't start.
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04:55
The development of technological
civilization is a third barrier.
civilization is a third barrier.
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第三个障碍是技术文明的发展。
05:00
Some say we already share our planet
with alien intelligences.
with alien intelligences.
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有人说我们已经在和外星人
共享我们的星球。
共享我们的星球。
2011年的一项研究表明，
大象可以合作解决问题。
大象可以合作解决问题。
05:05
A 2011 study showed that elephants
can cooperate to solve problems.
can cooperate to solve problems.
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05:10
A 2010 study showed
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2010年的研究表明，
人工饲养的章鱼可以识别不同的人。
05:12
that an octopus in captivity
can recognize different humans.
can recognize different humans.
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05:17
2017 studies show that ravens
can plan for future events --
can plan for future events --
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2017年的研究表明，
乌鸦可以为未来的事件做规划——
乌鸦可以为未来的事件做规划——
多么奇妙的、聪明的生物——
05:21
wonderful, clever creatures --
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但是它们想不出“突破摄星”计划，
05:24
but they can't contemplate
the Breakthrough Starshot project,
the Breakthrough Starshot project,
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如果今天，我们消失了，
05:27
and if we vanished today,
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05:29
they wouldn't go on
to implement Breakthrough Starshot --
to implement Breakthrough Starshot --
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它们也不会继续“突破摄星”之旅——
它们为什么要去呢?
05:32
why should they?
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进化的最终目标又不是太空旅行。
05:33
Evolution doesn't have
space travel as an end goal.
space travel as an end goal.
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05:37
There will be worlds where life
doesn't give rise to advanced technology.
doesn't give rise to advanced technology.
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有些世界里的生命
没有发明先进的技术。
没有发明先进的技术。
05:43
Communication across space --
that's a fourth barrier.
that's a fourth barrier.
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跨太空通信——这是第四个障碍。
也许先进的文明选择探索内部空间，
05:45
Maybe advanced civilizations
choose to explore inner space
choose to explore inner space
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而不是外太空，
05:49
rather than outer space,
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或者在小范围内而不是大范围上活动。
05:52
or engineer at small distances
rather than large.
rather than large.
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05:56
Or maybe they just don't want
to risk an encounter
to risk an encounter
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或者，他们只是不想冒险，
05:59
with a potentially more advanced
and hostile neighbor.
and hostile neighbor.
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遇到一个潜在的，更先进的敌对的邻居。
会有一些世界，无论出于什么原因，
06:03
There'll be worlds where,
for whatever reason,
for whatever reason,
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那里的文明要么保持沉默，
要么不花太长的时间交流。
要么不花太长的时间交流。
06:05
civilizations either stay silent
or don't spend long trying to communicate.
or don't spend long trying to communicate.
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06:12
As for the height of the barriers,
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至于障碍的高度，
大家的猜测都差不多。
06:14
your guess is as good as anyone's.
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06:18
In my experience,
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根据我的经验，
当人们进行数学计算，
06:19
when people sit down and do the math,
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通常得到的结论是，
银河系中存在数千个文明。
银河系中存在数千个文明。
06:21
they typically conclude there are
thousands of civilizations in the galaxy.
thousands of civilizations in the galaxy.
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06:27
But then we're back to the puzzle:
Where is everybody?
Where is everybody?
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但我们又回到了刚才的谜题：
外星人到底在哪儿?
外星人到底在哪儿?
06:32
By definition,
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根据定义，
不明飞行物——
包括我看到的那个——
包括我看到的那个——
06:33
UFOs -- including the one I saw --
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是身份“不明”的。
06:35
are unidentified.
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我们不能简单地推断
它们是宇宙飞船。
它们是宇宙飞船。
06:37
We can't simply infer they're spacecraft.
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你仍然可以饶有兴趣地
想象着外星人就在这里。
想象着外星人就在这里。
06:40
You can still have some fun
playing with the idea aliens are here.
playing with the idea aliens are here.
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06:45
Some say a summer civilization
did colonize the galaxy
did colonize the galaxy
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有人认为，夏季文明确实统治了银河系，
并给地球播下了生命的种子……
06:48
and seeded Earth with life ...
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06:51
others, that we're living
in a cosmic wilderness preserve --
in a cosmic wilderness preserve --
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还有人认为，我们生活在
宇宙的野生保护区——
宇宙的野生保护区——
动物园。
06:54
a zoo.
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06:56
Yet others --
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也有人说——
我们生活在一个模拟世界里。
06:58
that we're living in a simulation.
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只是程序员还没安排外星人出场而已。
07:00
Programmers just haven't
revealed the aliens yet.
revealed the aliens yet.
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07:03
Most of my colleagues though
argue that E.T. is out there,
argue that E.T. is out there,
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大多数我的同事认为
外星人是存在的，
外星人是存在的，
只是我们仍需寻找，
07:08
we just need to keep looking,
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这是有道理的。
07:09
and this makes sense.
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宇宙空间是巨大的。
07:11
Space is vast.
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识别一个信号是很难的，
07:13
Identifying a signal is hard,
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我们寻找的时间也不算很久。
07:15
and we haven't been looking that long.
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07:19
Without doubt, we should
spend more on the search.
spend more on the search.
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毫无疑问，我们应该在搜寻上加大投入。
这有助于理解
我们在宇宙中的位置。
我们在宇宙中的位置。
07:22
It's about understanding
our place in the universe.
our place in the universe.
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这个问题太重要了，不容忽视。
07:25
It's too important a question to ignore.
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07:29
But there's an obvious answer:
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但有一个显而易见的答案：
我们是孤单的。
07:31
we're alone.
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宇宙中只有我们存在。
07:33
It's just us.
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银河系中可能有一万亿颗行星。
07:34
There could be a trillion
planets in the galaxy.
planets in the galaxy.
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是否可能，我们是唯一有能力
思考这个问题的生物呢?
思考这个问题的生物呢?
07:38
Is it plausible we're the only creatures
capable of contemplating this question?
capable of contemplating this question?
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07:43
Well, yes, because in this context,
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没错，因为在这种情况下，
我们不知道一万亿这个数量大不大。
07:46
we don't know whether
a trillion is a big number.
a trillion is a big number.
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07:50
In 2000, Peter Ward and Don Brownlee
proposed the Rare Earth idea.
proposed the Rare Earth idea.
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2000年，彼得 · 瓦尔德和唐 · 布朗尼
提出了“稀有地球”的概念。
提出了“稀有地球”的概念。
还记得人们用来
07:55
Remember those four barriers
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07:57
that people use to estimate
the number of civilizations?
the number of civilizations?
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估算文明数量的四个障碍吗？
瓦尔德和布朗尼认为，
可能还有更多的障碍存在。
可能还有更多的障碍存在。
08:01
Ward and Brownlee said
there might be more.
there might be more.
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08:03
Let's look at one possible barrier.
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咱们来看一个可能存在的障碍。
08:05
It's a recent suggestion by David Waltham,
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这是地球物理学家大卫 · 沃尔瑟姆
最近提出的建议。
08:08
a geophysicist.
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08:10
This is my very simplified version
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这是我对大卫的复杂论证
做了简化处理的版本。
08:12
of Dave's much more
sophisticated argument.
sophisticated argument.
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08:16
We are able to be here now
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我们能够存在于此，
是因为地球的早期居民享受了
08:18
because Earth's previous
inhabitants enjoyed
inhabitants enjoyed
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40亿年的好天气——
08:20
four billion years of good weather --
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时好时坏，但基本上是温和的。
08:23
ups and downs but more or less clement.
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08:26
But long-term climate
stability is strange,
stability is strange,
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但是气候的长期稳定是值得探究的，
因为仅仅是天文影响，
08:29
if only because astronomical influences
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08:31
can push a planet
towards freezing or frying.
towards freezing or frying.
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都会让一个星球走向冰冻或炙烤。
有一种迹象表明，
我们的月球起了作用，
我们的月球起了作用，
08:36
There's a hint our moon has helped,
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08:38
and that's interesting
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这很有趣，
因为普遍流行的理论是，
08:40
because the prevailing theory is
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月球形成的时候，一个火星大小的
08:42
that the moon came into being when Theia,
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08:44
a body the size of Mars,
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天体忒伊亚
撞上了刚形成的地球。
08:46
crashed into a newly formed Earth.
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那次撞击的结果可能产生了
一个截然不同的地月系统。
一个截然不同的地月系统。
08:49
The outcome of that crash could have been
a quite different Earth-Moon system.
a quite different Earth-Moon system.
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08:54
We ended up with a large moon
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然而实际上，我们最终
得到的是一个大月球，
得到的是一个大月球，
这使得地球既可以稳定地轴向倾斜，
08:56
and that permitted Earth
to have both a stable axial tilt
to have both a stable axial tilt
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也可以缓慢地旋转。
09:00
and a slow rotation rate.
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这两个因素都影响着气候，
09:03
Both factors influence climate
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它们有助于缓和气候变化。
09:05
and the suggestion is that they've helped
moderate climate change.
moderate climate change.
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09:09
Great for us, right?
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对我们来说很棒，对吧？
09:11
But Waltham showed that if the moon
were just a few miles bigger,
were just a few miles bigger,
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但沃尔瑟姆指出，
如果月球的直径再大几英里，
如果月球的直径再大几英里，
情况就会不同了。
09:15
things would be different.
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地球的自转轴将会混乱地漂移。
09:16
Earth's spin axis
would now wander chaotically.
would now wander chaotically.
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气候会快速变化——
09:20
There'd be episodes
of rapid climate change --
of rapid climate change --
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这对复杂生命的形成非常不利。
09:23
not good for complex life.
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月亮的尺寸正合适：
09:25
The moon is just the right size:
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不大不小，正好。
09:27
big but not too big.
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一颗“刚刚好的”月球环绕着
一颗“刚刚好的”行星——
一颗“刚刚好的”行星——
09:30
A "Goldilocks" moon around
a "Goldilocks" planet --
a "Goldilocks" planet --
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也许这也是障碍之一。
09:33
a barrier perhaps.
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09:35
You can imagine more barriers.
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你可以想象更多的障碍。
例如，
09:37
For instance,
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简单的细胞是数十亿年前形成的……
09:38
simple cells came into being
billions of years ago ...
billions of years ago ...
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09:42
but perhaps the development
of complex life
of complex life
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但也许复杂生命的孕育和发展
需要一系列的不可能事件为前提。
09:45
needed a series of unlikely events.
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一旦地球上的生命发展为多细胞生物、
09:48
Once life on Earth
had access to multicellularity
had access to multicellularity
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复杂的遗传结构，
09:51
and sophisticated genetic structures,
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和性别，
09:53
and sex,
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新的机会就出现了：
09:54
new opportunities opened up:
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动物就会诞生。
09:56
animals became possible.
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09:58
But maybe it's the fate of many planets
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但是，可能许多行星的命运是
只有简单细胞级别的生命存在。
10:01
for life to settle
at the level of simple cells.
at the level of simple cells.
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10:06
Purely for the purposes of illustration,
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纯粹为了说明的目的，
让我再加四个障碍，
10:09
let me suggest four more barriers
to add to the four
to add to the four
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基于人们所说的阻碍了
文明交流渠道的四个障碍。
文明交流渠道的四个障碍。
10:12
that people said blocked the path
to communicative civilization.
to communicative civilization.
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10:17
Again, purely for the purposes
of illustration,
of illustration,
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强调一下，纯粹为了解释清楚，
我假设跨越每一个障碍的
几率是千分之一。
几率是千分之一。
10:21
suppose there's a one-in-a-thousand chance
of making it across each of the barriers.
of making it across each of the barriers.
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当然，可能会有不同的方法
来克服这些障碍，
来克服这些障碍，
10:25
Of course there might be
different ways of navigating the barriers,
different ways of navigating the barriers,
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有些机会可能不止千分之一。
10:28
and some chances will be better
than one in a thousand.
than one in a thousand.
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同样，也可能有另一些障碍，
10:31
Equally, there might be more barriers
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它们的机会只有百万分之一。
10:33
and some chances
might be one in a million.
might be one in a million.
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那么，就按这假设来看看会发生什么。
10:35
Let's just see
what happens in this picture.
what happens in this picture.
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10:39
If the galaxy contains a trillion planets,
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如果银河系里有一万亿颗行星，
那么有多少个行星上存在
像我们这样的文明，
像我们这样的文明，
10:41
how many will host a civilization
capable of contemplating like us
capable of contemplating like us
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能计划出“突破摄星”项目的文明？
10:47
projects such as Breakthrough Starshot?
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10:50
Habitability --
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适居性——
合适的行星围绕着合适的恒星——
10:51
right sort of planet
around the right sort of star --
around the right sort of star --
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一万亿里面有十亿个。
10:54
the trillion becomes a billion.
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稳定性——
10:56
Stability --
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永远保持良性的气候——
10:58
a climate that stays benign for eons --
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十亿里面有一百万个。
11:01
the billion becomes a million.
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必须孕育生命——
11:03
Life must start --
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11:05
the million becomes a thousand.
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百万里面有一千个。
拥有复杂的生命形式——
11:07
Complex life forms must arise --
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一千里面只有一个。
11:10
the thousand becomes one.
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必须开发出精密的工具——
11:12
Sophisticated tool use must develop --
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上千个星系中只有一颗行星能做到。
11:14
that's one planet in a thousand galaxies.
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2000
11:17
To understand the universe,
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为了了解宇宙，
必须发展科技和数学——
11:19
they'll have to develop the techniques
of science and mathematics --
of science and mathematics --
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百万个星系中只有一颗行星能做到。
11:22
that's one planet in a million galaxies.
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要接触其他恒星，
必须有社会性的生物，
必须有社会性的生物，
11:24
To reach the stars,
they'll have to be social creatures,
they'll have to be social creatures,
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能够用复杂的语法
11:27
capable of discussing
abstract concepts with each other
abstract concepts with each other
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11:29
using complex grammar --
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相互讨论抽象概念——
十亿个星系中只有一颗行星能做到。
11:31
one planet in a billion galaxies.
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而且它们必须避开灾难——
11:35
And they have to avoid disaster --
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不只是人祸，还有天灾。
11:36
not just self-inflicted
but from the skies, too.
but from the skies, too.
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围绕比邻星的那颗行星，
11:40
That planet around Proxima Centauri,
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去年被一个耀斑烤焦了。
11:43
last year it got blasted by a flare.
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11:47
One planet in a trillion galaxies,
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所以，一万亿星系中
只有一颗行星能做到，
只有一颗行星能做到，
可见的宇宙就是如此。
11:49
just as in the visible universe.
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我想我们是孤单的。
11:54
I think we're alone.
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11:57
Those colleagues of mine
who agree we're alone
who agree we're alone
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我的同事们，那些同意
人类是孤单存在着的同事们，
人类是孤单存在着的同事们，
常会看到摆在我们面前的障碍——
11:59
often see a barrier ahead --
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生物恐怖主义、
12:02
bioterror,
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全球变暖、战争。
12:04
global warming, war.
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12:06
A universe that's silent
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宇宙是沉默的，
因为科学技术本身会形成障碍，
12:09
because technology itself
forms the barrier
forms the barrier
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让真正先进的文明无法发展。
12:12
to the development
of a truly advanced civilization.
of a truly advanced civilization.
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听起来令人沮丧，是吧？
12:16
Depressing, right?
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12:19
I'm arguing the exact opposite.
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而我的观点恰恰相反。
12:22
I grew up watching "Star Trek"
and "Forbidden Planet,"
and "Forbidden Planet,"
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我是看《星际迷航》和《禁星》长大的，
并且我亲眼见过一次不明飞行物，
12:25
and I saw a UFO once,
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所以，这种宇宙独有的概念
肯定让我有些伤感。
肯定让我有些伤感。
12:26
so this idea of cosmic loneliness
I certainly find slightly wistful.
I certainly find slightly wistful.
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12:34
But for me,
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但对我来说，
宇宙的沉默是在呼喊，
12:36
the silence of the universe is shouting,
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“我们是幸运的生物。”
12:38
"We're the creatures who got lucky."
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12:40
All barriers are behind us.
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我们跨越了所有障碍。
我们是唯一扫清所有障碍的物种——
12:42
We're the only species
that's cleared them --
that's cleared them --
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唯一能够决定自己命运的物种。
12:45
the only species capable
of determining its own destiny.
of determining its own destiny.
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如果我们意识到这个星球的特殊性，
12:49
And if we learn to appreciate
how special our planet is,
how special our planet is,
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12:53
how important it is to look after our home
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意识到：照顾好我们的家园
12:56
and to find others,
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和找到其他生命的重要性；
意识到：我们十分幸运地
了解了宇宙的存在，
了解了宇宙的存在，
12:57
how incredibly fortunate we all are
simply to be aware of the universe,
simply to be aware of the universe,
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那么人类可能会存活得更长。
13:02
humanity might survive for a while.
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所有那些不可思议的事情，
13:05
And all those amazing things
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我们幻想外星人曾经做过的事，
13:06
we dreamed aliens
might have done in the past,
might have done in the past,
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也许就是我们的未来。
13:09
that could be our future.
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13:11
Thank you very much.
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非常感谢。
13:12
(Applause)
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（掌声）
ABOUT THE SPEAKER
Stephen Webb - Writer, scientistStephen Webb is a science fiction fan who's passionately interested in what the future might hold for our species.
Why you should listen
An early preoccupation with science fiction ended up influencing most of Stephen Webb's professional activity. It instilled in him a deep love of science and the scientific endeavor, which in turn led him to complete a PhD in theoretical particle physics. Isaac Asimov's story "The Fun They Had," about computerized homeschooling, prompted him to consider how digital technology might deepen students' learning, which in turn led to posts in a variety of UK universities.
And it was in the pages of a science fiction magazine that he first encountered the Fermi paradox, which kindled a lifelong fascination with the problem of why we see no signs of extraterrestrial intelligence -- and led to his book Where Is Everybody, which explores the question in detail. Webb hopes to pass on his love of science through his outreach work, and he is the author of a number of popular science books. He is working on New Light Through Old Windows, an anthology of classic science fiction tales; each tale appears alongside a commentary detailing the latest scientific thinking relating to the story's theme.
Stephen Webb | Speaker | TED.com