We often think of colonizing or even terraforming a planet, but how about colonizing every planet
in your galaxy, and not by spaceships but by self replicating machines.
Today I’d like to discuss von Neumann probes and some thoughts on the topic.
Now, while there are some who pronounce it von Neumann, in today’s episode I’ll be
pronouncing it von Neumann since I find it easier to say.
First of, von Neumann probes are self replicating spacecrafts, completely unmanned, that could
travel to a nearby solar system, grab natural resources in order to build some more probes,
and send them to other solar systems, and repeat.
So your probes will be going from star system to star system, landing on every planet possible
and building exact copies of itself from materials mined in each planet, until eventually your
probes have landed on every planet in your galaxy.
Now landing on every planet in your galaxy seems like a very tedious task, but it would
only take a few million years, ten million at the most to reach every one of the hundreds
of billions of exoplanets.
Although, that is assuming that these probes can go a substantial percentage the speed
of light, possibly 5, 10 or even 15% the speed of light, but either way the process would
only take a few million years.
To us that seems like a very long time but in the grand scheme of things, that’s nothing
in relation to the age of the universe.
Given that the Milky Way has been around for most of the age of the Universe, 13.6 billion
years out of the total 13.7, it’s more than fair to say that another civilization has
had more than enough time to send out some form of spacecraft that we would be able to
see.
If simple microbial life is common only in the slightest, let’s say only 1 in a thousand
exoplanets.
And another 1 in a thousand of those planets develops technologically advanced civilizations.
That still means tens of thousands of civilizations will have been capable at one point to be
able to send out a spacecraft, or a self replicating spacecraft like a von Neumann probe.
So not even one of those thousands of civilizations have built a single von Neumann probe?
According to the numbers, it seems very likely.
It leaves us with a paradox, and leaves us with the same conclusion as the Fermi paradox.
That either our numbers are wrong and planets like Earth are really rare or some other explanation.
A popular camp in the Fermi paradox is the Rare Earth hypothesis, that planets like Earth
are exceptionally rare.
It proposes that the steps needed for life to be able to develop, such as the correct
star and the evolution of life, are so improbable that perhaps only 1 planet in every galaxy
develops a technologically advanced civilization.
It leaves you with an annoying realisation that every civilization in each galaxy will
never meet another civilization and will always be asking “Are we alone?”.
However it does do a pretty good job of explaining why we aren’t seeing the galaxy teeming
with life.
With that being said, the civilization who sends out the first probe will be starting
this galaxy wide colonization for a reason.
There are many reasons why a civilization would do this, a popular one being to just
explore the galaxy.
If Humans attempted to colonize the galaxy in von Neumann probes, I’d say that this
would be one of the most common and most likely reasons.
Although saying that, it doesn’t feel like a very strong or plausible reason for Humans
to do it, but we’ll come back to this thought in a bit.
The aim of the exploration would be either just out of pure curiosity to get a better
idea of the planets in your galaxy or to search for any other life.
The problem is, the stream of data coming back from each probe, at far distances, will
take very long to reach Earth.
It’d be pretty impressive if we could receive the data, transmitted from hundreds of light
years away since you’d need a pretty loud transmitter.
We would have trouble detecting most of our own signals, even if we were only four light
years away at the closest star, Proxima Centauri.
If you want to ensure that you find life, if there is any, then have your probes first
target Earth-like exoplanets that have good chances of having life.
Once the probes reach the designated exoplanet they land and scan for any signs of life.
If the probe finds any life, whether simple or intelligent life, it sends the results
back to Earth.
If the probe doesn’t find any life then, after its created several other self-replicating
probes, it settles down and sets up shop on the planet, turning on every so often to scan
the nearby surroundings for any signs of life.
This continuous scan ensures you that your probes will find any existing life or any
upcoming life, if there is any on the planet.
Of course, this plan can be flawed if a planet with life, doesn’t have the life distributed
evenly.
A habitable tidally locked planet, for instance, in most cases, could only have life on a narrow
band between the extremely hot and cold sides.
After collecting data from enough probes, then overtime we could construct a very accurate
map of the galaxy.
Although I’m not entirely sure if we’re capable of doing something as detailed and
complex as that.
To send out von Neumann probes in order to get a better understanding of how life starts
and how it evolves would be another reason, albeit a rather ambitious one.
Unfortunately, it looks like we can’t find out much more than what we already know about
how life starts and the evolution of life, just from what we can find out here on Earth.
It looks like we can only make guesses from now on.
But observing it actually occurring and taking samples during life's early stages would prove
to be very useful.
Now, a particular xenophobic civilization may decide to launch von Neumann probes to
kill all life in the galaxy, often the probes are instead called Berserkers.
Same as before, the probes reach designated exoplanets, land and scan for life.
This time, however, if they find any signs of life, whether simple or intelligent life,
the probe destroys it.
In the scenario where the probe doesn’t find any life then, once it has created several
other copies of itself, it settles down and sets up shop on the planet, and as before,
turning on every so often to scan the nearby surroundings for any signs of life.
If you really want to destroy all life in your galaxy then just program your probes
to look for not just intelligent life but just any living life.
Destroying life that hasn’t gained intelligence, microbial life for example, prevents that
life from potentially evolving and gaining intelligence over the course of several hundred
million years.
Within a few million years, your probes will have erased all other life in your galaxy,
if there was any.
If one particular probe comes across a planet filled with life, it would be useful for the
probe to build other self replicating probes, but not to send off to other planets but to
help killing life on the planet.
One probe killing an entire planet of life would take a very long time, and the probe
probably wouldn’t have enough fire power to kill everything.
And anyways, once the newly made probes have finished their job, they can always go off
to look for more life.
In no way can I see Humans doing such a procedure just to kill all life in the galaxy.
Such a xenophobic civilization could only be this hostile due to a previous observation
of battling civilizations or a previous encounter with a hostile and dangerous civilization.
Or perhaps the civilisation is so cautious that they would prefer to kill all life off
before any other civilizations become too advanced rather than risking the possible
danger.
Or maybe it’s just in their nature.
This plan could end up being exceptionally dangerous if you’re not careful.
The probes could decide to target your civilization, seen as there’s a planet full of life.
And there wouldn’t be much you could do in the way of stopping these machines.
Their sole purpose is to find and kill life.
If necessary they will create however many probes they need in order to defeat your civilization.
On a more positive note, these probes could serve as protectors for the entire galaxy,
seen as they're spread in every corner of the galaxy, it wouldn’t take long to get
to any location.
If a fight breaks out somewhere, some probes could head over in no time and intervene.
In the event where your civilization is in danger of becoming extinct, it’s in your
best interest to save it.
One way is to send off von Neumann probes carrying life to go into hiding to preserve
your civilization, with the aim of hopefully rebuilding into a thriving civilization.
A pre-cautious civilization may do this in advance, despite not being in danger.
They might have backup civilizations scattered around the galaxy so that they can’t be
wiped out.
Colonizing a planet or moon achieves the same purpose.
If a natural disaster wipes all life out on your home planet, your civilization will still
survive, because you have a colony on a different planet or moon that was completely unaffected.
But instead you could send out von Neumann probes to introduce life on other worlds by
carrying embryos or possibly a probe capable of 3D printing Humans.
The probes are more than capable of carrying the complete Human history and every book
needed since these days you can fit a lot of information in such a small storage space.
And you could probably carry all the main animal embryos in a size as small as a briefcase.
Reasons why a civilization would want to do this vary.
It could be because their civilization is going to be wiped out inevitably or simply
because they want for there to be more life in the galaxy.
I can see Humans sending von Neumann probes out as our successor species if we were going
to die.
Although saying that, we probably wouldn’t if we were able to stop whatever was going
to kill us or evacuate beforehand.
Another idea, I suppose, is to terraform a planet or moon, possibly even preparing the
location for future missions or bases.
Another use for von Neumann probes is for communication relays.
Most of our radio and TV signals don’t go very far.
We would have trouble detecting most of our own signals, even only four light years away
at the closest star, Proxima Centauri.
So it would be pretty useful to have a network of communication relays, one at every solar
system.
The only reason you would use self replicating spacecrafts instead of normal spaceships to
do this is because self replicating spacecrafts could do it a lot faster than mass producing
them here on Earth.
Von Neumann probes could also be used to build megastructures, a Dyson sphere for example.
Even for a Type II civilization, building megastructures can take a very long time,
even just mining the material needed takes a long time.
However with the help of thousands of self replicating probes it wouldn’t take as long.
If Humans were to make use of von Neumann probes, there are a lot of decisions we would
have to make.
For instance how far do you go in the probes capabilities?
What would you enable these probes to do?
Would you give them defence mechanisms or not?
If they turn on you, you don’t want them to be too powerful.
Another thing, they’ll need strong transmitters to ensure the data reaches Earth from far
distances.
That is, if the probes aren’t used as communication relays.
Furthermore, would you mass produce the machines here on Earth and keep releasing them or just
send a few and let those probes do the self replicating.
Everything we discussed in this episode, I think it’s fair to say that it’s possible.
I wouldn’t say it’s possible to Humans just yet, but definitely within the next few
centuries.
Comment down below your thoughts on von Neumann probes.
Make sure you subscribe for more content on astronomy and futurism.
If you enjoyed this video check out my most recent video, a previous video or my playlist
on the Fermi paradox.
Thank you so much for watching, have a nice day.