Is there a limit to technological progress Clment Vidal

Many generations have felt
they’ve reached the pinnacle

of technological advancement,

yet look back 100 years,

and the technologies
we take for granted today

would seem like impossible magic.

So will there be a point

where we reach an actual limit
of technological progress?

And if so, are we anywhere near
that limit now?

Half a century ago,

Russian astronomer Nikolai Kardashev
was asking similar questions

when he came up with a way
to measure technological progress,

even when we have no idea exactly
what it might look like.

Anything we do in the future
will require energy,

so Kardashev’s scale
classifies potential civilizations,

whether alien civilizations out there
in the universe or our own,

into three levels based
on energy consumption.

The tiny amount of energy
we currently consume

pales next to what we leave untapped.

A Type I, or planetary civilization,

can access all the energy resources
of its home planet.

In our case, this is the 174,000
terawatts Earth receives from the Sun.

We currently only harness
about 15 terawatts of it,

mostly by burning solar energy
stored in fossil fuels.

To approach becoming
a Type I civilization,

we would need to capture solar energy
more directly and efficiently

by covering the planet with solar panels.

Based on the most optimistic models,

we might get there
within just four centuries.

What would be next?

Well, the Earth only gets a sliver
of the Sun’s energy,

while the rest of its 400 yottawatts
is wasted in dead space.

But a Type II, or stellar civilization,

would make the most
of its home star’s energy.

Instead of installing solar panels
around a planet,

a Type II civilization would install them
directly orbiting its star,

forming a theoretical structure
called a Dyson sphere.

And the third step?

A Type III civilization would harness
all the energy of its home galaxy.

But we can also think of progress
in the opposite way.

How small can we go?

To that end, British cosmologist
John Barrow

classified civilizations by the size
of objects they control.

That ranges from mechanical structures
at our own scale,

to the building blocks of our own biology,

down to unlocking atoms themselves.

We’ve currently touched the atomic level,
though our control remains limited.

But we potentially could
go much smaller in the future.

To get a sense of the extent
to which that’s true,

the observable universe is 26 orders
of magnitude larger than a human body.

That means if you zoomed out
by a factor of ten 26 times,

you’d be at the scale of the universe.

But to reach the minimum length scale,
known as the Planck length,

you would need to zoom in 35 times.

As physicist Richard Feynman once said,
“There’s plenty of room at the bottom.”

Instead of one or the other,

it’s likely that our civilization will
continue to develop

along both Kardashev and Barrow scales.

Precision on a smaller scale lets us
use energy more efficiently

and unlocks new energy sources,
like nuclear fusion,

or even antimatter.

And this increased energy lets us
expand and build on a larger scale.

A truly advanced civilization, then,

would harness both stellar energy
and subatomic technologies.

But these predictions weren’t made
just for us humans.

They double as a possible means

of detecting intelligent life
in the universe.

If we find a Dyson sphere
around a distant star,

that’s a pretty compelling sign of life.

Or, what if, instead of a structure that
passively soaked up all the star’s energy,

like a plant,

an alien civilization built one that
actively sucked the energy out of the star

like a hummingbird.

Frighteningly enough, we’ve observed
super dense celestial bodies

about the size of a planet

that drain energy out
of a much bigger star.

It would be much too premature to conclude

that this is evidence
of life in the universe.

There are also explanations
for these observations

that don’t involve alien life forms.

But that doesn’t stop us
from asking, “What if?”

许多代人都觉得
他们已经达到

了技术进步的顶峰,

但回顾 100 年,

我们今天

认为理所当然的技术似乎是不可能的魔法。

那么

,我们是否会达到技术进步的实际极限

如果是这样,我们
现在是否接近这个极限?

半个世纪前,

俄罗斯天文学家尼古拉·
卡尔达舍夫提出了类似的问题

,他提出了
一种衡量技术进步的方法,

即使我们不知道
它究竟是什么样子。

我们未来所做的任何事情
都需要能源,

因此卡尔达舍夫的量表
根据能源消耗将潜在文明(

无论
是宇宙中的外星文明还是我们自己的文明)

分为三个级别

我们目前消耗的少量能量

与我们尚未开发的能量相比相形见绌。

I 型,或行星文明,

可以获取
其母星的所有能源资源。

在我们的例子中,这是
地球从太阳接收到的 174,000 太瓦。

我们目前只利用
大约 15 太瓦的

能量,主要是通过燃烧
储存在化石燃料中的太阳能。

为了接近
成为 I 型文明,

我们需要

通过用太阳能电池板覆盖地球来更直接、更有效地捕获太阳能。

根据最乐观的模型,

我们可能会
在短短四个世纪内到达那里。

接下来会是什么?

好吧,地球只获得了一小
部分太阳能量,

而其余的 400 瓦
则被浪费在了死空间中。

但是 II 型或恒星文明

将充分
利用其母星的能量。

II型文明不会在行星周围安装太阳能电池板,而是将它们直接安装在
围绕其恒星运行的轨道上,

形成一种
称为戴森球的理论结构。

第三步呢?

III 型文明将
利用其母星系的所有能量。

但我们也可以
以相反的方式思考进步。

我们能走多小?

为此,英国宇宙学家
约翰巴罗

根据他们控制的物体的大小对文明进行分类。

范围从
我们自己规模的机械结构,

到我们自己的生物学的组成部分

,再到解锁原子本身。

我们目前已经触及原子级别,
尽管我们的控制仍然有限。

但我们
未来可能会变得更小。

为了了解这在
多大程度上是真实的

,可观测的宇宙
比人体大 26 个数量级。

这意味着如果你
缩小 10 倍 26 倍,

你将处于宇宙的规模。

但要达到最小长度比例
,即普朗克长度,

您需要放大 35 倍。

正如物理学家理查德费曼曾经说过的那样,
“底部有足够的空间。”

我们的文明很可能会
继续

沿着卡尔达舍夫和巴罗尺度发展,而不是其中一个。

更小规模的精确度使我们能够
更有效地利用能源

并解锁新能源,
如核聚变

甚至反物质。

而这种增加的能量使我们能够
在更大的范围内扩展和建设。

那么,一个真正先进的文明

将同时利用恒星能量
和亚原子技术。

但这些预测
不仅仅针对我们人类。

它们兼作

探测
宇宙中智能生命的可能手段。

如果我们
在一颗遥远的恒星周围找到一个戴森球,

那是一个非常引人注目的生命迹象。

或者,如果不是像植物那样
被动吸收恒星所有能量的结构

,而是

一个外星文明建造了一个像蜂鸟一样
主动从恒星吸收能量的结构

令人恐惧的是,我们已经观察到

了行星大小的超致密天体

,它们
从更大的恒星中汲取能量。

现在下结论

说这是
宇宙中存在生命的证据还为时过早。

对于这些

不涉及外星生命形式的观察,也有解释。

但这并不能阻止
我们问,“如果呢?”