-
Not Synced
Imagine a distant future when humans
reach beyond our pale blue dot,
-
Not Synced
forge cities on planets thousands of
light-years away,
-
Not Synced
and maintain a galactic web of trade
and transport.
-
Not Synced
What would it take for our civilization
to make that leap?
-
Not Synced
There are many things to consider—
how would we communicate?
-
Not Synced
What might a galactic government
look like?
-
Not Synced
And one of the most fundamental of
all:
-
Not Synced
where would we get enough energy
to power that civilization—
-
Not Synced
its industry, its terraforming
operations, and its starships?
-
Not Synced
An astronomer named Nikolai Kardashev
proposed a scale
-
Not Synced
to quantify an evolving civilization’s
increasing energy needs.
-
Not Synced
In the first evolutionary stage, which
we’re currently in,
-
Not Synced
planet-based fuel sources like fossil
fuels,
-
Not Synced
solar panels and nuclear power plants
-
Not Synced
are probably enough to settle other
planets inside our own solar system,
-
Not Synced
but not much beyond that.
-
Not Synced
For a civilization on the third and final
stage, expansion on a galactic scale
-
Not Synced
would require about 100 billion
times more energy
-
Not Synced
than the full 385 yotta joules our sun
releases every second.
-
Not Synced
Barring a breakthrough in exotic physics,
-
Not Synced
there’s only one energy source that could
suffice: a supermassive black hole.
-
Not Synced
It’s counterintuitive to think of black
holes as energy sources,
-
Not Synced
but that’s exactly what they are,
thanks to their accretion disks:
-
Not Synced
circular, flat structures formed by matter
falling into the event horizon.
-
Not Synced
Because of conservation of angular
momentum,
-
Not Synced
particles there don’t just plummet
straight into the black hole.
-
Not Synced
Instead, they slowly spiral.
-
Not Synced
Due to the intense gravitational field
of the black hole,
-
Not Synced
these particles convert their potential
energy to kinetic energy
-
Not Synced
as they inch closer to the event horizon.
-
Not Synced
Particle interactions allow for this kinetic
energy
-
Not Synced
to be radiated out into space at an
astonishing matter-to-energy efficiency:
-
Not Synced
6% for non-rotating black holes, and
up to 32% for rotating ones.
-
Not Synced
This drastically outshines
nuclear fission,
-
Not Synced
currently the most efficient widely
available mechanism
-
Not Synced
to extract energy from mass.
-
Not Synced
Fission converts just 0.08% of a
Uranium atom into energy.
-
Not Synced
The key to harnessing this power
may lie in a structure
-
Not Synced
devised by physicist Freeman Dyson,
known as the Dyson sphere.
-
Not Synced
In the 1960s, Dyson proposed that an
advanced planetary civilization
-
Not Synced
could engineer an artificial sphere
around their main star,
-
Not Synced
capturing all of its radiated energy to
satisfy their needs.
-
Not Synced
A similar, though vastly more complicated
design
-
Not Synced
could theoretically be applied to
black holes.
-
Not Synced
In order to produce energy, black holes
need to be continuously fed –
-
Not Synced
so we wouldn’t want to fully cover it
with a sphere.
-
Not Synced
Even if we did, the plasma jets that shoot
from the poles
-
Not Synced
of many supermassive black holes
-
Not Synced
would blow any structure in
their way to smithereens.
-
Not Synced
So instead, we might design a sort of
Dyson ring,
-
Not Synced
made of massive, remotely
controlled collectors.
-
Not Synced
They’d swarm in an orbit around
a black hole,
-
Not Synced
perhaps on the plane of its
accretion disk, but farther out.
-
Not Synced
These devices could use mirror-like
panels
-
Not Synced
to transmit the collected energy
to a powerplant,
-
Not Synced
or a battery for storage.
-
Not Synced
We’d need to ensure that these collectors
are built at just the right radius:
-
Not Synced
too close and they’d melt from
the radiated energy.
-
Not Synced
Too far, and they’d only collect a tiny
fraction of the available energy
-
Not Synced
and might be disrupted by stars orbiting
the black hole.
-
Not Synced
We would likely need several Earths
worth of highly reflective material
-
Not Synced
like hematite to construct
the full system––
-
Not Synced
plus a few more dismantled planets
to make a legion of construction robots.
-
Not Synced
Once built, the Dyson ring would be
a technological masterpiece,
-
Not Synced
powering a civilization spread
across every arm of a galaxy.
-
Not Synced
This all may seem like wild speculation.
-
Not Synced
But even now, in our
current energy crisis,
-
Not Synced
we’re confronted by the limited
resources of our planet.
-
Not Synced
New ways of sustainable energy
production will always be needed,
-
Not Synced
especially as humanity works towards
he survival
-
Not Synced
and technological progress of our species.
-
Not Synced
Perhaps there’s already a civilization
out there
-
Not Synced
that has conquered these
astronomical giants.
-
Not Synced
We may even be able to tell by seeing the
light from their black hole periodically dim
-
Not Synced
as pieces of the Dyson ring pass between
us and them.
-
Not Synced
Or maybe these superstructures are
fated to remain in the realm of theory.
-
Not Synced
Only time––and our scientific
ingenuity––will tell.