So the ultimate question, I feel like we've all
had that exact moment. Oh, absolutely. Just lying
in bed, staring up at the ceiling, or maybe you're
out camping somewhere, looking at a sky completely
full of stars. Yeah. And the sheer weight of
it just hits you. You just have to ask, are we
alone? It is entirely the question. I mean, it's
arguably the driving force behind a huge chunk
of human philosophy, religion, and really for
the last century or so, some incredibly hard
data -driven science. And that is exactly what
we are digging into today. because this question
has shifted gears massively over time. It really
has. It used to just be, you know, guys in togas
arguing over wine in ancient Greece about whether
other worlds existed. But looking at the research
stack we have in front of us for today's deep
dive, we aren't talking about philosophy anymore.
Not at all. We are talking about radio telescopes,
exoplanet data and some really high stakes statistics.
Right. We have moved from just wondering to actively
looking. And we were looking for something very,
very specific. So, welcome to the Deep Dive.
Today we are tackling the big one, Extraterrestrial
Intelligence, or ETI. And just to set the expectations
right out of the gate for you listening, we aren't
reviewing the latest sci -fi blockbuster today.
Yeah, leave your lightsabers at the door. Exactly.
There are no laser beams or little green guys
and flying saucers in this stack of notes. No,
unfortunately. Or, well, perhaps fortunately,
depending on how you view the prospect of an
alien invasion. Very true. We are talking about
the actual methodical scientific hunt for our
cousins in the cosmos a real deal we're gonna
unpack the history of this search the mathematical
probability that someone is actually out there
and Frankly the genuinely terrifying concept
of the great silence. The silence is the heavy
part It's the background noise or lack thereof
of this entire field because if the math says
they should be here Why is it so incredibly quiet?
It's spooky. So let's just unpack this we need
to start with the shift of perspective The sources
talk a lot about the Copernican principle, or
I think it was also called the principle of mediocrity.
Right, yeah. This is really the foundation of
everything we're discussing. For a very long
time, humanity just operated under this assumption
that we were the main character of the universe.
Right, like the whole stage was built specifically
for us. Exactly. The lights were arranged for
us. That's the pre -Copernican view. Everything
revolves around Earth. literally and metaphorically.
Until Copernicus comes along. Right. Copernicus
comes along and says, actually, Earth is just
a planet revolving around the sun. And that is
the first major blow to our collective ego. A
tough pill to swallow, for sure. But the second
blow, which is much more relevant to ETI, is
the basic logic that follows that discovery.
If Earth is just a world, and those stars up
there are other suns, then those other suns likely
have worlds too. And if those are worlds? Then
they might be inhabited. It's such a massive
logical leap. It is, and that logical leap is
what officially moved aliens from mythology into
the realm of scientific speculation. It's that
idea of mediocrity you mentioned. The idea that
there is absolutely nothing special about Earth.
Right, like we aren't some cosmic VIPs. Exactly.
If life happened here, Basic chemistry and physics
dictate that it should happen elsewhere. But,
um, when we say happened elsewhere, the research
stack makes it clear we need to be really precise
with our language here. I notice that The scientists
get a little twitchy when people just say they're
looking for life. They do get twitchy because
life is a massive bucket. I mean, if we find
microbial slime under the ice on a moon of Jupiter,
that is technically life. And it would be huge.
It would be the single biggest discover in human
history. But that is not what ETI is. Right.
We aren't trying to have a deep conversation
with space moles. Exactly. We are talking about
extraterrestrial intelligence. We're looking
for hypothetical beings with cognitive abilities
that are similar to, or perhaps far superior
to, human beings. Which brings me to a phrase
in the text that I seriously had to read twice.
It said some researchers actually prefer the
term extraterrestrial technological instantiations.
Ah, yes. Extraterrestrial technological instantiations.
It just rolls right off the tongue, doesn't it?
It sounds like something a corporate lawyer would
call an alien just to avoid a liability lawsuit.
Yeah. Why the intense complexity? It's all about
avoiding our own earth -centric bias. Words like
civilization or species, they automatically imply
structures that we understand. Like cities or
governments or biological breeding. Right. But
a truly alien intelligence might not have any
of those things. They might be a massive hive
mind. Or maybe a swarm of conscious nanobots.
Oh, that's wild to think about. The term technological
instantiation just strips all our baggage away
and asks one simple question. Is there something
out there manifesting technology that we can
actually detect? So we literally do not care
if it's a society, a single giant supercomputer,
or a cloud of highly educated gas, just as long
as it builds a radio transmitter. Correct. We
are looking for the tech, not necessarily the
biology, and that leads right into the other
major distinction the research highlights, which
is sentience versus sapience. I will be completely
honest with you. I usually use those interchangeably.
Most people do. In sci -fi movies, they always
say sentient life when they mean smart life.
But in this field, the distinction is absolutely
vital. Sentience is just the basic ability to
feel or experience things. Like having senses.
Right. A dog is sentient. A cat is sentient.
They feel pain. They feel joy. They get hungry.
But we aren't spending billions of dollars scanning
the stars for space cats. As much as the internet
would absolutely love that, no, we are not. We
are looking for sapience. Wisdom? The actual
ability to think abstractly, calculate math,
reflect on the universe, and engineer solutions.
There was a specific term for that too, right?
Yes. There's a term coined by the science fiction
author Karen Anderson called softency. Softency.
It essentially means being wise or perhaps possessing
a wisdom that is actually far greater than human
standards. So the main takeaway for you as you're
listening to this is we are actively filtering
out the bacteria and the space cows. We are hunting
for entities. that can do calculus. Okay, so
we know exactly what we are looking for. The
next big question is, what are the actual odds
we find it? Because when you look at the sheer
mind -numbing scale of the universe, surely we
can't be the only ones. That is the gut intuition.
It's often called the space's big argument. The
late Stephen Hawking was a massive proponent
of this. He argued that simply based on the raw
numbers, it is mathematically highly improbable
for life not to have emerged somewhere else.
But science doesn't really like to run on gut
intuition. We need a rigorous framework. And
that is where the famous Drake equation comes
into play in our notes. The Drake equation. It
is legendary in astronomy. Frank Drake came up
with it way back in 1961, basically just as a
way to organize the agenda for the very first
meeting on SETI. It's that long, terrifying string
of variables that's supposed to spit out a number,
right? N equals r times fp and so on. That's
the one. It is essentially a probabilistic argument.
It asks a series of sequential filtering questions.
First it asks how many stars are born per year
in our galaxy. Okay, that seems measurable. We
can figure that out. We can. Then it asks what
percentage of those stars actually have planets
orbiting them? And thanks to modern telescopes
like Kepler, We basically know that answer now,
right? It's close to all of them. Correct. 20
years ago, we were completely guessing. But now
we know the galaxy is absolutely teeming with
planets. But then the equation gets significantly
trickier. How so? Well, it asks, how many of
those planets sit in the habitable zone and can
support life? Then, how many of those actually
develop life? Then, how many of those develop
intelligence? And crucially, How many of those
develop technology that actively releases detectable
signals into space? It definitely feels like
the further down that list you go, the more we
are just throwing darts blindfolded. We absolutely
are. We have zero data for those later variables.
But the most important variable in the entire
equation and the one that usually depresses the
scientists is the very final one, the letter
L. What does L stand for? The length of time
a civilization actually releases detectable signals
into space. Why is that specific one so critical?
Just think about it in terms of our own history.
We have only had radio technology for a little
over 100 years. If advanced civilizations tend
to, say, blow themselves up with nuclear weapons,
or completely destroy their biosphere within
200 years of discovering high technology, then
L is a very, very small number. Oh, I see. And
if L is small? Then the number of civilizations
active right now drops to near zero. They might
pop up across the galaxy like fireflies, flash
for a single second, and go completely dark before
anyone else ever sees them. That is incredibly
grim. But there was a study in our research stack.
from 2020, I believe, that actually tried to
crunch these exact numbers using modern astrophysics
data. Yes, a fascinating study by Wespi and Consulis
over at the University of Nottingham. They took
a strict Copernican approach. Meaning they assumed
Earth isn't special. Right. They assumed that
if a planet is Earth -like, life evolves on a
timeline very similar to ours. And they actually
came up with a specific number of alien civilizations.
They did. They estimated that there could be
about 36 active alien civilizations in our galaxy
right now. Thirty -six. I really have to say,
my reaction to that number was super mixed. On
one hand, hey, it's proof we have neighbors.
On the other hand, out of 400 billion stars in
the Milky Way, only 36. That feels like looking
for a needle in a haystack the size of the Pacific
Ocean. It is a very conservative estimate, yes,
but let's just play with that number for a second.
36 advanced civilizations out there right now.
It sounds exciting. We could start a galactic
federation. But there is a huge catch. A massively
depressing catch. The study also mathematically
estimated the average distance between us and
any of those 36 civilizations. Lay it on me.
17 ,000 light years. Oof. Yeah. OOF is exactly
right. 17 ,000 light years means that radio waves,
which travel at the absolute speed of light,
take 17 ,000 years just to get there. So wait,
if we point a satellite and say hello today.
They won't even hear it until the year 19 ,026.
And if they reply immediately, we get the text
message back 34 ,000 years from right now. Assuming
human beings are even still here to check the
inbox. So an actual back and forth conversation
is basically impossible. A two -way conversation
is completely impossible. We are essentially
dealing with cosmic archaeology at that point.
We might be catching signals from a brilliant
civilization that has already been dead for 10
,000 years. And this brutal reality leads us
directly into the Fermi paradox. The famous,
where is everybody problem. Right. If the math
says they should be there, even if it's just
36 of them scattered around, why is the sky so
totally quiet. We have absolutely zero verifiable
observation of ETI. No giant ships, no Dyson
spheres, no stray radio signals, just pure static.
It is the great silence. And it is deeply spooky.
It is genuinely like walking into a massive,
heavily decorated room for a party, but it's
completely empty. Is everyone just playing hide
-and -seek or did something terrible happen to
all the guests? Well, the good news is we aren't
just sitting around wondering and feeling spooked.
Humanity is actively trying to break that silence.
Let's talk about how we actually search. Because
I think most people just picture Jodie Foster
in the movie Contact sitting on the hood of a
car with big headphones on. That is definitely
the classic pop culture image of SETI, the search
for extraterrestrial intelligence. And that method
is passive listening. We build these massive
radio dishes, point them at the sky, and just
scan the radio spectrum, hoping to catch a whisper.
But why radio? Why not use lasers or? I don't
know, gravity waves. Well, we actually are looking
into those things now. There's a whole subfield
called optical SETI looking for pulsed lasers.
But radio is the classic historical choice because
it is very cheap, energetically speaking, and
radio waves pass right through the thick dust
clouds in the galaxy. It is just the most logical,
efficient way to shout across the cosmos. And
we aren't just listening to random static on
every channel either. We're looking for very
specific frequencies, right? The notes mention
something called the water hole. This is such
a beautiful, elegant concept. Let's say you wanted
to meet a friend in New York City, but your phones
are dead and you couldn't agree on a place or
a time beforehand. Where would you go? Probably
Times Square. Or maybe the clock at Grand Central
Station. Exactly. You pick a landmark that both
of you inherently understand is important. In
the vast radio spectrum of the universe, the
landmark is 1420 megahertz. Why that specific
number? That is the exact frequency that neutral
hydrogen atoms emit. Hydrogen is the single most
common element in the universe. It is the fundamental
water in the ocean of the cosmos. Every single
physicist in the universe, whether they are human
or alien, would know about hydrogen. Ah, I see.
So the logic is if they want to be found, they
would naturally broadcast on the hydrogen channel
because they know we'd be listening there. Precisely.
It is the universal water cooler. But we have
also tried being the noisy ones ourselves. We've
done active SETI. We have. And this is highly
controversial. Stephen Hawking, for instance,
thought this was a genuinely terrible idea. He
basically said, if you are walking through a
dark jungle, you do not shout to let the apex
predators know exactly where you are. But we
ignored that and did it anyway. We sent the Pioneer
plaque. We did. The Pioneer plaque is an actual
physical message bolted onto the side of a probe
we launched back in the 70s. It has a diagram
of a human man and woman and a mathematical map
showing exactly where our solar system is relative
to specific pulsars. It's quite literally a map
directly to our front door. Yep. And then there
was the famous Arecibo message. Right, in 1974.
Frank Drake and Carl Sagan composed that one.
It was a powerful radio signal beamed directly
at the M13 star cluster. It essentially counts
from 1 to 10, shows the atomic numbers for the
elements of life, a pixelated graphic of our
DNA double helix, and a little stick figure of
a human. Have we heard anything back from that
one? Well, M13 is 25 ,000 light years away, so
maybe check back with me in about 50 ,000 years.
Right, I'll put it on my calendar. But we have
had moments where we actually thought we heard
something answering back. The source material
highlights the very famous wow signal. Oh, the
wow signal. August 1977, the big year radio telescope
in Ohio. What exactly happened there? Because
this is the one that every single documentary
always cites. The telescope was scanning that
exact water hole frequency we just talked about,
1420 megahertz, and suddenly the data spiked.
It hit a massive intensity, roughly 30 times
stronger than the normal background noise of
space. That's a huge jump. It was. And it lasted
for exactly 72 seconds, which happens to be exactly
how long that specific telescope could track
a fixed point in the deep sky as the Earth naturally
turned. So it was incredibly loud, and it was
perfectly placed on the hydrogen channel. It
looked completely perfect. It was narrowband.
It was incredibly strong, and it clearly originated
from deep space. The astronomer on duty, Jerry
Amon, was so utterly shocked by the print out
that he grabbed a red pen, circled the data code,
and wrote, wow, in the margin. But we went back
the very next day to listen again, absolute silence.
We have pointed telescopes back at that exact
spot hundreds of times since. complete silence.
That is the ultimate frustration of the scientific
method. If you can't replicate it, it isn't proof.
It just becomes a really cool ghost story. Exactly.
And we have had much more recent false alarms,
too. Do you remember the massive news cycle about
the Chinese telescope FAST back in 2022? I do
remember that. FAST is that absolutely massive
dish built into a natural basin in China. They
reported some very suspicious signals that they
thought might actually be alien civilizations.
The Internet completely went wild over that.
But context is everything in this field. Dan
Wertheimer, who is a chief scientist for SETI,
looked closely at the data. His conclusion was
totally definitive. It was radio frequency interference.
RFI. So wait, it was just us? It was just us.
It could be a random cell phone tower, a poorly
shielded microwave oven in the break room, or
a rogue satellite passing overhead. We are constantly
polluting our own sky with radio noise. Trying
to find a delicate alien signal right now is
like trying to hear a single whisper across a
packed football stadium while everyone else is
screaming. That makes sense. So no smoking gun
yet, but surely the government knows something
we don't. We just had those huge hearings in
2023. Ah, the UAP hearings. That was definitely
a cultural shift, having actual lawmakers openly
discussing unidentified anomalous phenomena in
front of cameras. But it is really important
to distinguish what is happening there. And our
sources are very clear on this. Right. We are
just looking at the official reporting here,
completely neutrally. Exactly. The government's
primary concern in those hearings is strictly
national security. They are worried about unauthorized
drones, next generation spycraft and foreign
penetrating our airspace. They are not necessarily
confirming the existence of ETI. But what is
their actual official stance on aliens? Officially
the White House stance, and this goes all the
way back to a formal statement in 2011, is that
there is absolutely no evidence of extraterrestrial
contact. But the simple fact that Congress is
even holding these public hearings shows how
the topic is rapidly moving from fringe conspiracy
to mainstream political discourse. Now I want
to pivot to what I honestly think is the most
mind -bending part of our entire research stack
today. Yeah. The idea that we have been looking
for the totally wrong thing this whole time.
Oh, the post -biological hypothesis? Yes. Yeah.
Because we naturally always picture aliens as
biological creatures. You know, gray guys, big
black guys, maybe some tentacles of the movie.
directors feeling creative. Right, flesh and
blood beings. But leading experts like the astronomer
Royal Martin Rees or astrophysicist Mario Livio
strongly suggest that assumption is incredibly
naive. Just think about our own rapid human history.
We developed primitive radio astronomy roughly
a hundred years ago. How long until we develop
truly super intelligent, self -replicating AI?
Honestly, maybe another 50 years. 100 tops. Exactly.
The window of time where a civilization is purely
biological and actively communicating in space
is incredibly tiny. It is a cosmic blip. As soon
as we invent the super machines, the machines
will likely completely take over the exploration
of the galaxy. Because biology is just too fragile
for space. We need pressurized air, clean water,
highly specific temperatures. Machines don't
need any of that. Correct. So if an alien civilization
manages to survive its own technological adolescence
without destroying itself, it almost certainly
transitions into a purely machine -based intelligence.
They could build autonomous probes that easily
last for billions of years in the vacuum of space.
So those 36 active civilizations we talked about
earlier from the Nottingham study, they might
not be actual people living in alien cities.
They might just be 36 silent super servers. quietly
orbiting a black hole somewhere. Or 36 dormant
automated probes just sitting on asteroids waiting
to detect a radio signal. And this perfectly
connects to the Kardashev scale mentioned in
the sources. Refresh me and the listener on that
one. I know it deals with how we measure a civilization's
energy consumption. Right. The Kardashev scale
categorizes civilizations by their total energy
use. A type I civilization controls all the available
energy of its entire home planet. Think of that
like a basic campfire. Humanity is barely even
a campfire yet. We aren't even a full type one.
Okay, so what is a type two? A type two civilization
controls the entire energy output of its host
star. Think of a Dyson Sphere, which is a hypothetical
massive shell built completely around a sun to
harvest every ounce of its energy. That is essentially
a nuclear reactor the exact size of a solar system.
That is just staggering. And Type 3? Type 3 controls
the energy of an entire galaxy. They are harvesting
the raw power of billions of stars simultaneously.
An Attack 3 civilization definitely wouldn't
be worried about growing wheat crops or breathing
oxygen. Not at all. They would likely be pure
computation at that point. So if we ever do detect
a verified signal, it is overwhelmingly likely
to come from a machine, not a mortal biological
creature. Which makes the entire idea of first
contact even more complicated to wrap your head
around. Let's just play this out. Let's say we
do it. The signal finally comes in. It is absolutely
verified by every telescope on Earth. What actually
happens to us down here? This brings up what
sociologists call ontological shock. The cultural,
religious, and psychological impact on humanity
would be completely shattering. The notes actually
mention a specific historical analogy for this.
The Columbian Exchange. Yeah, and it is a famously
dark one. When the so -called old world met the
new world in 1492, it was not a polite, friendly
cultural exchange of ideas. It was an absolute
catastrophe for the receiving civilization. Right.
Massive disease, brutal conquest, and total societal
collapse. Exactly. So if humanity is the new
world in this scenario and a highly advanced
type two machine civilization suddenly shows
up, the difference in technology would be so
incredibly vast that Conquest might not even
be the right word for it. We might just be like
ants standing in the way of a galactic highway
construction project. That ties right into the
dark forest theory, doesn't it? The terrifying
idea that maybe the reason the universe is so
silent is because everyone else is actively hiding,
completely terrified of being noticed by the
big predators. It is a very real mathematically
modeled possibility. But to be fair to the sources,
there are optimists in the field, too. Some scientists
argue that aggression and expansion are purely
primitive biological treats. A civilization that
manages to survive for a million years might
have naturally evolved completely past the concept
of war. We can certainly hope they are peaceful
philosophers and not planet bulldozers. And speaking
of hope, I absolutely have to mention the one
lighter cultural note in our research stack,
because not everyone on earth is terrified of
the dark forest. Some people are apparently ready
to throw a welcome party. Ah yes, the great state
of New Mexico. They are completely head of the
curve on this one. They really are. New Mexico
officially declared a state holiday back in 2003,
Extraterrestrial Culture Day, and they specifically
set it for the second Tuesday of February every
year. Right around Valentine's Day. Exactly.
So while the rest of the world is stressing out
buying roses and chocolates, New Mexico is out
there officially celebrating our hypothetical
cosmic neighbors. It really is a nice sentiment.
It essentially says, hey, we are ready to be
friends whenever you are. I really like that
energy. Less of an Independence Day laser beam
situation and more of a peaceful arrival situation.
Let's definitely hope for arrival. So let's wrap
this deep dive up. We have covered a massive
amount of ground today. We have gone from the
original Copernican Revolution realizing we aren't
the special center of the universe, all the way
to the nitty -gritty math of the Drake equation.
We looked at the hard numbers, the mathematical
possibility of 36 active civilizations balanced
against the completely crushing reality of a
17 ,000 light -year distance. We talked about
passive listening on the waterhole frequency,
the mystery of the wow signal, and the very real,
somewhat intimidating chance that we are actually
searching for immortal machines rather than little
green men. And, of course, the existential risks.
The idea that the Great Silence might actually
be a safety feature of the universe, not a bug.
It is a lot to process. But going through all
this incredible research today, there is one
final thought that really stuck with me. A sort
of haunting, provocative possibility that I honestly
cannot shake. Oh, what's that? Well, we worry
so much about the vastness of space. The sheer
distance between stars. But what about the vastness
of time? Go on. The universe is roughly 13 .8
billion years old. Modern humans have been here
for what? A microscopic blink of an eye in comparison.
Isn't it entirely possible that the Milky Way
galaxy actually was completely teeming with intelligent
life? Just maybe billions of years ago. Maybe
there were massive empires spanning across the
stars while Earth was still just a ball of cooling
magma. And they are all completely gone now.
Exactly. We might have just missed the ultimate
cosmic party. We might be eagerly shouting hello
into an empty room simply because everyone else
packed up and left a really, really long time
ago. Wow. So we might literally be walking through
a cosmic graveyard, mistaking the ancient monuments
for silence. On that incredibly cheery existential
note, it really does make you appreciate the
fleeting moment we have right now on this little
blue dot, doesn't it? It absolutely does. We
are here. We are loud. And at least for right
now, we are actively listening. Thanks for taking
this deep dock with us today. Keep looking up,
everyone. See you next time.