Could we steal the power of a black hole? - Fabio Pacucci

翻译人员: C Cheng 校对人员: Yu Xie

Imagine a distant future when humans reach beyond our pale blue dot,

想象一下，在遥远的未来，人类 可及的疆域超越了我们淡蓝色的星球，

forge cities on planets thousands of light-years away,

在几千光年之外的星球上建造城市，

and maintain a galactic web of trade and transport.

维护着银河系的贸易 与交通网络。

What would it take for our civilization to make that leap?

以我们现在的文明， 要如何实现这一飞跃？

There are many things to consider— how would we communicate?

其中有许多事情需要考虑—— 我们该如何沟通？

What might a galactic government look like?

银河系政府将会是 什么样子？

And one of the most fundamental of all:

其中最基本的一个问题是：

where would we get enough energy to power that civilization—

我们将从哪里获得足够的 能源来驱动这个文明——

its industry, its terraforming operations, and its starships?

它的工业、外星环境改造 以及及宇宙飞船？

An astronomer named Nikolai Kardashev proposed a scale

一位名叫尼古拉·卡尔达肖夫 （Nikolai Kardashev）的天文学家

to quantify an evolving civilization’s increasing energy needs.

提出了一个量表，用以量化文明 在进化中对能量不断增长的需求。

In the first evolutionary stage, which we’re currently in,

在第一个进化阶段， 也就是我们现在所处的阶段,

planet-based fuel sources like fossil fuels,

基于行星的燃料资源， 比如化石能源，

solar panels and nuclear power plants

太阳能电池板和核电站

are probably enough to settle other planets inside our own solar system,

也许足够让我们在太阳系内 其它星球上定居，

but not much beyond that.

但也仅此而已。

For a civilization on the third and final stage,

对于处在第三，也是 最后阶段的文明来说，

expansion on a galactic scale would require about 100 billion times

在银河系的范畴内进行拓展则需要

比太阳每秒释放的 385 尧焦耳 还要多出 100 亿倍的能量。

more energy than the full 385 yotta joules our sun releases every second.

Barring a breakthrough in exotic physics,

除非在奇特物理学上取得重大突破，

there’s only one energy source that could suffice:

否则只有一种能量来源 可以满足需要：

a supermassive black hole.

超大质量黑洞。

It’s counterintuitive to think of black holes as energy sources,

把黑洞视为能量来源 是一种反直觉的想法，

but that’s exactly what they are, thanks to their accretion disks:

但它们的自然特性就是如此。 这要归结于它们的吸积盘（Accretion disk）：

circular, flat structures formed by matter falling into the event horizon.

一种圆形扁平结构，由掉落在 事件视界（Event horizon）内的物质构成。

Because of conservation of angular momentum,

由于角动量守恒，

particles there don’t just plummet straight into the black hole.

那里的颗粒物质 并不直接跌入黑洞，

Instead, they slowly spiral.

而是开始缓慢盘旋。

Due to the intense gravitational field of the black hole,

由于黑洞强大的引力场，

these particles convert their potential energy to kinetic energy

这些颗粒

在一寸寸接近事件视界时， 将它们的势能转化成了动能。

as they inch closer to the event horizon.

Particle interactions allow for this kinetic energy

颗粒之间的相互作用使该动能

to be radiated out into space

得以辐射到宇宙空间。

at an astonishing matter-to-energy efficiency:

其间的物质到能量的 转化效率非常惊人：

6% for non-rotating black holes, and up to 32% for rotating ones.

非旋转黑洞是 6%， 而旋转黑洞则可以高达 32%。

This drastically outshines nuclear fission,

这大大胜过了核裂变，

currently the most efficient widely available mechanism

这一目前最为有效且广泛使用的

to extract energy from mass.

从物质中提取能量的方法。

Fission converts just 0.08% of a Uranium atom into energy.

裂变只能将 0.08% 的 铀原子转化为能量。

The key to harnessing this power may lie in a structure

开发利用这一能量的关键， 也许就在于一个由物理学家

devised by physicist Freeman Dyson, known as the Dyson sphere.

弗里曼·戴森（Freeman Dyson）设计的， 被称为“戴森球”的结构。

In the 1960s, Dyson proposed that an advanced planetary civilization

在 20 世纪 60 年代， 戴森提出，先进的星球文明

could engineer an artificial sphere around their main star,

可以设计建造一个围绕在 其主要恒星周围的人造球体，

capturing all of its radiated energy to satisfy their needs.

用它来捕获恒星所辐射出的 所有能量，从而满足他们的需求。

A similar, though vastly more complicated design

一个类似，却更为复杂的设计

could theoretically be applied to black holes.

可以在理论上用于黑洞。

In order to produce energy, black holes need to be continuously fed—

为了制造能量， 黑洞需要不间断的补给——

so we wouldn’t want to fully cover it with a sphere.

所以我们不会想用一个球体 把它全部覆盖。

Even if we did, the plasma jets that shoot from the poles

即使我们这样做了，

从许多超大质量黑洞的两极 射出的等离子射流

of many supermassive black holes

would blow any structure in their way to smithereens.

也会把任何挡路的 建筑结构炸得粉碎。

So instead, we might design a sort of Dyson ring,

所以，取而代之， 我们也许可以设计一种“戴森圈”，

made of massive, remotely controlled collectors.

由巨大的远程控制的收集器构成。

They’d swarm in an orbit around a black hole,

它们沿着环绕黑洞的轨道成群移动，

perhaps on the plane of its accretion disk, but farther out.

远离吸积盘， 但与其保持在同一平面上。

These devices could use mirror-like panels

这些装置可以用类似于镜子的嵌板

to transmit the collected energy to a powerplant,

把收集到的能量传送给动力装置

or a battery for storage.

或电池，来进行存储。

We’d need to ensure that these collectors are built at just the right radius:

我们需要确保这些收集器 建造在正确的半径上:

too close and they’d melt from the radiated energy.

如果太近，它们 会因辐射出的能量而融化。

Too far, and they’d only collect a tiny fraction of the available energy

太远的话，它们则只能 收集到极小部分的可获能量，

and might be disrupted by stars orbiting the black hole.

而且可能会被那些绕着 黑洞运行的恒星摧毁。

We would likely need several Earths worth of highly reflective material

我们很可能需要 相当于几个地球储量的，

like hematite to construct the full system—

如赤矿石这样的高反光材料 来建造整个系统——

plus a few more dismantled planets to make a legion of construction robots.

再加上几个被拆卸了的星球， 以组建一支机器人施工军团。

Once built, the Dyson ring would be a technological masterpiece,

一旦建成，这个戴森圈 将是一个科技杰作。

powering a civilization spread across every arm of a galaxy.

它将驱动文明在整个 银河系进行传播。

This all may seem like wild speculation.

这一切看起来似乎是一个疯狂臆测。

But even now, in our current energy crisis,

但是即使是现在， 在当前的能源危机中，

we’re confronted by the limited resources of our planet.

我们也面临着地球资源有限的问题。

New ways of sustainable energy production will always be needed,

我们将始终需要新的方法来 制造可持续能源，

especially as humanity works towards the survival

特别是当人类这一物种在为生存

and technological progress of our species.

和科技进步而努力的时候。

Perhaps there’s already a civilization out there

也许，已经有文明

that has conquered these astronomical giants.

征服了这些天体巨人。

We may even be able to tell

也许，我们甚至可以对此有所察觉：

by seeing the light from their black hole periodically dim

当我们看到从他们的黑洞 射出的光时而变暗时，

as pieces of the Dyson ring pass between us and them.

那是戴森圈的部件 在我们与他们之间穿过。

Or maybe these superstructures are fated to remain in the realm of theory.

或许这些超级构造将注定 停留在理论范畴。

Only time— and our scientific ingenuity— will tell.

只有时间——和我们的科学智慧 ——才知晓答案。