Could we move beyond our small blue planet

我們能夠離開我們所在的藍色小行星嗎？

to establish colonies in the multitude of star systems out there?

去那許多星系那裡建立殖民地？

This question's a pretty daunting one.

這是相當令人怯步的一個疑問

There are around 300 billion stars in the galaxy,

在星系中，大約有三千億顆星

which is about 160,000 light-years across.

而它們大約飛行了十六萬光年的距離

So far we've sent a single spacecraft outside our solar system,

迄今，我們已經發射出一個太空船飛到太陽系外

trudging along at 0.006% of the speed of light.

用光速的0.006% 速度（約每秒十八公里）跋涉

At that rate, it would take over 2.5 billion years

照這個速率，它將花費超過二十五億年的時間

just to get from one end of the galaxy to the other.

才能從銀河系的底端到另一端

And then there's the question of human survival.

我們也需要考慮到人類生存的議題

The gulf between stars is simply enormous.

星與星之間的隔閡是相當大的

We couldn't live sustainably on most planets,

在大多數的星球上，我們可能無法持續生存

and we require a lot of resources to stay alive.

我們需要很多資源才能存活下來

And yet, decades ago, scholars found that it's theoretically possible

然而，在十幾年前，學者卻找出理論上可行的方式

to not just spread human civilization across the galaxy,

讓我們不僅可以將人類文明散播在星系各處

but to do so quite quickly,

還可以很快的達成這個目標

without breaking any known laws of physics.

也不需要打破任何已知的物理法則

Their idea is based on the work of a mathematician named John von Neumann,

他們的想法源自於一位數學家—— 約翰·馮·諾伊曼的研究

who designed on paper machines that could self-replicate

他設計了未經實踐機器原型，機器人可以自我複製

and create new generations of themselves.

它們自己創造自己新的一代

These would later come to be known as von Neumann machines.

這此之後被稱為馮諾伊曼機器人

In the context of space exploration,

在太空探索中

von Neumann machines could be built on Earth

泛紐曼機器能夠在地球上開發

and launched into space.

然後發射到外太空

There, the self-sufficient machines would land on distant planets.

在那裡自足的機器人將會著陸在遙遠的行星

They would then mine the available resources and harvest energy,

它們將採集可用資源和收集能量

build replicas of themselves,

建立它們自己的複製品

launch those to the nearest planets,

再把它們發射到最近的行星

and continue the cycle.

一直持續不斷循環

The result is the creation of millions of probes

這個結果將會創造數百萬個太空探測器

spreading outwards into the universe like a drop of ink in a fishbowl.

像把一滴墨水滴入魚缸一樣，擴張到全宇宙

Scholars crunched the numbers and found that a single von Neumann machine

學者們計算著數字發現單一馮諾伊曼機器人

traveling at 5% of the speed of light

用光速的百分之五的速度移動著

should be able to replicate throughout our galaxy in 4 million years or less.

應該能夠在四百萬年內，佈滿整個星系

That may sound like a long time,

這可能聽起來是一段很長時間

but when you consider that our universe is 14 billion years old,

但當你考量到我們的宇宙已經一百四十億歲

on a cosmic scale, it's incredibly fast -

從一個宇宙規模來看，它難以置信地迅速

the equivalent of about 2.5 hours in an entire year.

相當於一整年的二個半小時

Creating von Neumann machines would require a few technologies

創造馮諾伊曼機器人將會需要一些技術

we don't have yet,

目前我們還沒達到

including advanced artificial intelligence,

包括高等的人工智慧

miniaturization,

迷你化

and better propulsion systems.

和更進步的推進系統

If we wanted to use them to spread actual humans throughout the galaxy,

如果我們打算使用它們將人類散播到整個銀河系

we would need yet another technological leap -

我們將會需要其它的科技跳躍——

the ability to artificially grow biological organisms and bodies

一個人工發育生物體和身體的能力

using raw elements and genetic information.

使用未加工的元素和基因資訊

Regardless, if in the last billion years

無論如何，如果在過去十億年

an alien civilization created such a machine

一個外星的文明世界創造了一個機器

and set it multiplying its way toward us,

它朝著我們飛來

our galaxy would be swarming with them by now.

我們的銀河系現在早就被它們淹沒了

So then where are all these machines?

所以現在這些機器人在哪裡？

Some astronomers, like Carl Sagan,

有一些天文學家，像卡爾．薩根

say that intelligent aliens wouldn't build self-replicating machines at all.

提到智慧型外星人根本不會建立自我複製機器人

They might hurtle out of control,

它們可能失去控制猛衝

scavaging planets to their cores in order to keep replicating.

直到把其他行星的核心都啃食掉，以維持複製的能力

Others take the machines' absence as proof

其他天文學家則以目前尚未發現這些機器人做為證明

that intelligent alien civilizations don't exist,

表示外星的文明智慧根本不存在

or that they go extinct before they can develop the necessary technologies.

或在它們可以發展出所需的技術之前，它們就已經滅絕

But all this hasn't stopped people from imagining

但這些證據都沒辦法讓人們不去想像

what it would be like if they were out there.

假設外星人就在宇宙中，會是什麼樣子的

Science fiction author David Brin

科幻小說作者大衛．布林

writes about an universe in which many different von Neumann machines exist

寫下有許多不同的馮諾伊曼機器人存在的宇宙

and proliferate simultaneously.

不停的繁殖

Some are designed to greet young civilizations,

一些被設計用來迎接初期的文明

others to locate and destroy them before they become a threat.

其他的被用來尋找並摧毀另一些可能構成威脅的初期文明

In fact, in Brin's story "Lungfish,"

事實上，在布林的故事「肺魚」

some von Neumann machines are keeping a close watch over the Earth right now,

一些馮諾伊曼機器人現在就近監視地球

waiting for us to reach a certain level of sophistication

等到我們達到某種程度的複雜性

before they make their move.

它們就會採取行動了

For now, all we have is curiosity and theory.

現在，我們只保有好奇心與理論推測

But the next time you look at the night sky,

但是，下次當你仰望夜晚星空時

consider that billions of self-replicating machines

想到數十億的自我複製的機器人

could be advancing between stars in our galaxy right now.

現在在我們銀河系星星之間前進

If they exist, one of them will eventually land on Earth,

假如外星人存在，它們其中之一最終將落在地球上

or maybe, just maybe, they're already here.

但或許，只是或許，它們早已在這裡