Is there a limit to technological progress? - Clément 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 stars 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 10, 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 of a 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?
