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

譯者: Lilian Chiu 審譯者: Helen Chang

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

想像在遙遠的未來，

人類能夠到地球以外的地方，

forge cities on planets thousands of light-years away,

在數千光年以外的星球上打造城市，

and maintain a galactic web of trade and transport.

維持銀河的貿易與交通網路。

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

我們的文明需要什麼 才能達成這樣的大躍進？

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

有許多要考量的——

我們要如何通訊？

What might a galactic government look like?

銀河政府會是什麼模樣？

And one of the most fundamental of all:

還有，最基本的考量之一：

where would we get enough energy to power that civilization—

我們要從哪裡找到足夠的能源 來供應文明使用——

its industry, its terraforming operations, and its starships?

用在產業上、用來將外星環境地球化、

用在星艦上？

An astronomer named Nikolai Kardashev proposed a scale

不斷演化的文明 對能源的需求會不斷增加，

to quantify an evolving civilization’s increasing energy needs.

天文學家尼古拉 · 卡爾達肖夫 提出了一種尺度來將之量化。

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

在演化的第一階段， 也是我們現在所處的階段，

planet-based fuel sources like fossil fuels,

地球上的燃料來源，如化石燃料、

solar panels and nuclear power plants

太陽能板，以及核能發電廠，

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

大概足以供應

我們這太陽系中 其他星球的定居所。

but not much beyond that.

但無法超出這範圍太多。

For a civilization on the third and final stage,

對於第三階段 也就是最終階段的文明而言，

expansion on a galactic scale would require about 100 billion times

銀河規模的擴張所需的能量

大約是我們的太陽 每秒釋放的 385 佑（10²⁴）焦耳

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

再乘以一千億倍。

Barring a breakthrough in exotic physics,

除了奇異物理的突破之外，

there’s only one energy source that could suffice:

就只有一個能源來源 可以滿足這個條件：

a supermassive black hole.

超大質量黑洞。

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

將黑洞視為能源違反直覺，

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

但實情就是如此， 因為它們具有吸積盤：

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

由落入事件視界的物質

所形成的圓形扁平結構。

Because of conservation of angular momentum,

因為角動能守恆，

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

那裡的粒子不會直直落入黑洞當中。

Instead, they slowly spiral.

反之，它們會緩慢地 以螺旋軌道移動。

Due to the intense gravitational field of the black hole,

因為黑洞的引力場很強，

these particles convert their potential energy to kinetic energy

當這些粒子越緩緩接近事件視界時，

as they inch closer to the event horizon.

它們的位能會轉換為動能。

Particle interactions allow for this kinetic energy

粒子交互作用會讓這種動能

to be radiated out into space

被放射到太空中，

at an astonishing matter-to-energy efficiency:

且物質轉為能量的效率高得驚人：

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

非旋轉黑洞是 6%，

旋轉黑洞高達 32%。

This drastically outshines nuclear fission,

這遠超過目前最有效率且廣為使用的

currently the most efficient widely available mechanism

能量粹取機制：核融合，

to extract energy from mass.

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

核融合只能將鈾原子的 0.08%

轉換為能量。

The key to harnessing this power may lie in a structure

若要利用這種力量， 關鍵在於戴森球，

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

物理學家弗里曼 · 戴森 發明出來的一種結構。

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

在六○年代，戴森提出一個理論， 他認為先進的行星文明

could engineer an artificial sphere around their main star,

能夠在主星球的周圍 建造出一個人工球體，

capturing all of its radiated energy to satisfy their needs.

捕捉所有從星球放射出去的 能量，來滿足他們的需求。

A similar, though vastly more complicated design

理論上，可以把類似

但複雜許多的設計應用在黑洞上。

could theoretically be applied to black holes.

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

為了產生能量， 必須持續「餵食」黑洞，

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

所以不能用球體把它整個包住。

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

就算我們真的做了， 許多超大質量黑洞

of many supermassive black holes

從兩極所放射出的電漿噴流

would blow any structure in their way to smithereens.

也會把任何擋在路上的結構給粉碎。

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

所以，我們可能要 改成設計一種戴森環，

made of massive, remotely controlled collectors.

由遠端控制的大型收集器所組成。

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

它們會成群移動， 繞著黑洞形成一個環，

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

也許這個環會和吸積盤 在同一個平面上，但更外圍。

These devices could use mirror-like panels

這些裝置可以用類似鏡子的面板

to transmit the collected energy to a powerplant,

將收集到的能量傳輸給電廠，

or a battery for storage.

或放入電池中儲存。

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

我們必須要確保這些收集器 被建造在正確的半徑上，

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

太靠近黑洞，它們會被 放射出來的能量給熔化。

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

太遠就只能收集到 可得能量中的一小部分，

and might be disrupted by stars orbiting the black hole.

且可能會被繞行黑洞的星體給打斷。

We would likely need several Earths worth of highly reflective material

我們可能會需要如赤鐵礦 這類高度反射性的材料，

且需要等同好幾個地球的量， 才能建造完整的系統——

like hematite to construct the full system—

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

另外再多拆解幾個行星

來製造一支建設機器人軍團。

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

一旦建造出來，戴森環 會是一項技術傑作，

powering a civilization spread across every arm of a galaxy.

供給能源給散佈在 銀河系各處的文明。

This all may seem like wild speculation.

這一切可能像是狂野的推測。

But even now, in our current energy crisis,

但，就連現在，在我們 目前的能源危機中，

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

我們也面臨到地球上的資源有限。

New ways of sustainable energy production will always be needed,

永遠都會需要製造 永續能源的新方法，

especially as humanity works towards the survival

特別是當人類正在朝向

and technological progress of our species.

我們物種的生存與科技進展努力。

Perhaps there’s already a civilization out there

也許在外頭某處已經有一個文明

that has conquered these astronomical giants.

成功征服了這些天文巨物。

We may even be able to tell

我們可能可以看得出來，

by seeing the light from their black hole periodically dim

因為能夠看見當部分戴森環 通過我們和他們之間時，

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

黑洞放射出來的光 會有週期性地變暗。

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

或者，也許這些超級結構 注定永遠都只會是理論。

Only time— and our scientific ingenuity— will tell.

只有時間和我們的科學創造力

才能斷定一切。