了解宇宙是如何运行的（2010）

How the Universe Works S08E03

Part 4 Jan. 30, 2022, 2:58 p.m.

narrator:
Rocky planets like ours
are ideal for hosting life,
但它们很脆弱
but they're fragile.
这种脆弱意味着
And this fragility means
the universe
宇宙可以迅速过滤掉智慧生命
could filter out
intelligent life quickly.
♪
我们发现了非常剧烈的恒星爆♥炸♥
we've discovered
very violent star explosions
比如伽马射线爆发
like gamma-ray bursts.
这些能量足够强大它们甚至可以
These are powerful enough,
they may sterilize planets
毁灭整个星系的行星
even across an entire galaxy.
即使聪明的物种在自然现象中幸存下来
Narrator:
And even if intelligent species
他们仍然可能被过滤掉
survive natural phenomenon,
因为他们有可能
they may still be filtered out
按下了自毁的按钮
by hitting
the self-destruct button.
勒布:根据我们自己的经验
Loeb: As we can tell from
our own experience,
从我们开始开♥发♥技术的那一刻起
the moment that we started
developing technology,
我们也开♥发♥了自我毁灭的技术手段
we also developed the means
for our own destruction
通过改变地球的气候
by changing the climate
on our planet,
以及通过开♥发♥大规模杀伤性武器
by developing weapons
of mass destruction.
所以很有可能
And so it's quite possible
that civilizations
足够先进的文明是短暂
that are advanced enough
are short-lived.
如果它们是短命的
And if they're short-lived,
那就能解释为什么在这个时间点上
that would explain why,
at this point in time,
很少有机会
there are very few of them
that might be around
与我们交流了
to communicate with us.
找到一个灭绝的外星文明的遗迹
Narrator: Finding the relics
of an extinct alien civilization
可能是对人类的终极宇宙警告
could be the ultimate cosmic
warning for the human race.
斯特里克:如果我们在那里发现一个
Stricker: If we were to find
a civilization out there
可能因污染或冲突而
that may have destroyed
themselves by pollution
毁灭自己的文明
or conflict,
那几乎就像盯着一面镜子一样
it would be almost like
staring into a mirror,
这将是一个非常可怕的预兆
and it would be
a very grim foreshadowing
也许这是对我们地球上的人类来说是一个教训
and maybe a lessons-learned
for us humans here on earth.
我们只能希望一些先进的外来物种
Narrator: We can only hope
that some advanced alien species
能逃脱宇宙的致命过滤器
escaped the universe's
deadly filter.
但即使外星人仍然存在
But even if e.T.S still exist
out there,
第一次接触的可能性仍然很大
the odds are still stacked
against first contact.
♪
关于我们与外星人接触的故事
one other way that we've got
this alien-contact story
另一个有点错误的方式是物理学定律
a bit wrong is just down to
the laws of physics.
每一天，宇宙的物理现象
Narrator: Every day,
the physics of the cosmos
都让我们联♥系♥的机会越来越少
makes our chances
of contact worse
因为我们的宇宙在膨胀
because our universe
is expanding,
而且膨胀得很快
and it's expanding fast.
[爆♥炸♥]
[ explosion ]
♪
2018年2月——
narrator:
February 2018 --
俄克拉何马大学的天体物理学家
astrophysicists
at the university of oklahoma
发现了一系列38亿光年以外的
find a potential series
of rogue planets
流浪行星
3.8 billion light-years away.
大小介于月球和木星之间
Ranging between the size
of our moon and jupiter,
这将是我们在银河系外发现的
these would be
the first alien worlds
第一个外星世界……
ever discovered
outside our galaxy...
……也许是许多中的第一个
...And maybe the first of many.
仅我们的星系就有数万亿颗行星
Our galaxy alone
has trillions of planets.
可观测的宇宙有数万亿个星系——
The observable universe
has trillions of galaxies --
据估计大约有2万亿
it's estimated about 2 trillion.
所以有数万亿？
So trillions of trillions?
拜托
Come on.
但是发现系外行星并不能保证
Narrator: But finding
exoplanets is no guarantee
找到外星生命
of finding alien life.
当涉及到与外星人接触时
And when it comes to contacting
extraterrestrials,
我们的努力却遭遇了沉默
our efforts
have met with silence.
奥卢西伊:我们对生命的探索已经失败
Oluseyi: Our search for life
has come up empty.
我们需要改变策略吗？
Do we need
to change our tactics?
我们做错什么了吗？
Are we doing something wrong?
卡罗尔:我认为要找到
Carroll: I think it's gonna be
very, very hard
我们正在寻找的外星智慧生物
to find
extraterrestrial intelligence
是非常非常困难的
the way that
we're looking for it.
我们必须非常非常幸运
We would have to get
really, really lucky.
但我不认为我们会有好运
But I don't think
we're gonna get lucky.
我认为，如果我们想知道
I think that if we want to know
宇宙中是否存在生命
whether there's life out there
in the cosmos,
我们必须去访问它
we have to go visit it.
我们已经把新的地平线探测器
Narrator: We've sent
the new horizons probe
发射到太阳系数十亿英里（约16亿公里）外的冥王星
billions of miles across
the solar system to pluto.
也许有一天，我们能够发射宇宙飞船
Perhaps one day we'll be able
to send spacecraft
穿越宇宙
across the universe
在遥远的流浪行星上寻找外星生命
to search for alien life
on distant rogue planets.
♪
但是，如果一艘宇宙飞船离开我们的星系去访问这些新的世界
but if a craft left our galaxy
to visit these new worlds,
它的任务将是艰难的
its mission would be tough
这要感谢宇宙物理学
thanks to the physics
of the cosmos.
从我们在银河系的角度来看
From our perspective
here in the milky way,
平均而言，每个星系都在远离我们
every galaxy is, on average,
receding away from us.
看起来好像没人喜欢我们
It looks like nobody likes us
想要离我们越远越好
and is trying to get as far away
from us as possible.
这是因为我们巨大的宇宙在膨胀
Narrator: This is because
our giant universe is expanding.
弗里斯:当我们谈论膨胀的宇宙时
Freese: When we talk about
the expanding universe,
我们并不是指星系在做一些积极的事情
we don't mean that galaxies
are doing something active
来逃离彼此
to run away from one another.
实际上，是潜在的空间在膨胀
Actually, it's the underlying
space that's expanding,
星系被嵌在其中
and the galaxies
are embedded in that,
这就是导致万物
and that's what causes
everything to move apart
远离万物的原因
from everything else.
距离我们300万光年
Narrator:
The regions of the universe
以内的宇宙区域
within 3 million light-years
of us
正在以每秒45英里（约72.4公里）的速度扩张
are expanding
at around 45 miles a second.
也就是每小时超过16万英里（约26万公里）