
Dissolving the Fermi Paradox - laurex
http://slatestarcodex.com/2018/07/03/ssc-journal-club-dissolving-the-fermi-paradox/
======
rossdavidh
This whole idea of "dissolving" the Fermi paradox seems to be missing the
point. Everyone knows that we have, in fact, not observed an alien
civilization, so one of the factors in the Drake equation (or one we should
have put in) is responsible. But, is it that there is very little chance of
life evolving, or intelligence? Or is it that intelligence tends to be short
lived? Or is it because long-lived intelligence uses methods of communication
we cannot observe, and is responsible enough not to colonize all the good
planets? The consequences for us are large, depending on which one of those it
is. Merely saying "well it's not that surprising that one of those factors is
tiny" is not really relevant to the question of, which factor is it that is
tiny?

~~~
danShumway
No, what the article is saying is that when you rely on distributions of
outcomes from the Drake equation rather than averages, it's much more likely
that you'll get tiny results.

You don't need extremely low values in the Drake equation to end up with
nearly no aliens. It's actually kind of likely that we're (close to) alone,
even without a crazy complicated theory to justify one of the values being
nearly zero.

This is missing the point that many people do treat the Fermi Paradox like
it's a real paradox - like there's some kind of fundamental universal
principle that has to almost universally block out all life or all
communication.

The article is saying you don't need it. It's good enough to say "well, life
might just be sort of uncommon, and even in that scenario we shouldn't be
surprised that we got a very low roll."

That is a surprising conclusion. No, we don't know the exact cause, but it
means that the Fermi Paradox might not be a _paradox_ , in the sense that it
doesn't directly contradict all of our priors.

Think of it like the difference between saying, "Trump won the election
because we fundamentally don't understand how democracy works in practice",
and "Trump won the election because he had a 1 and 5 chance of winning, and
sometimes 20% chance events happen."

~~~
ianai
I find the notion that we have enough information to even guess at where life
is let alone that we can assume there is none downright laughable to the point
of obscenity. We know a lot less about this universe than it takes to make
even sensible guesses as to generalizations about the nature of life in the
universe.

~~~
TeMPOraL
Our best-effort guesses are _literally the best we can do_. Pretty much by
definition, dismissing them because "we know so little" means taking a view
that's _worse than that guess_.

~~~
leeeeech
> literally

excuse me, but no. Our best-effort guesses might be the best we could
literally do. But there is no need to be that literal, or literal at all. As
long as the uncertainty range includes 0.5, it's OK, but merely a test of how
much we know as a fact as opposed to intuitively. And at that, the equation
can surely be blown up further. Why would it be optimal?

------
ravenstine
You can calculate all the probabilities you want all day and night, but
there's still no evidence. Until we have a _frequency_ of how often life
occurs, rather than a single occurrence, speculated probability doesn't mean
anything. Especially when we can't even create life in a lab. (If I remember
correctly, we've been able to create amino acids using early-Earth conditions,
but we haven't really been able to create something like RNA.)

The Fermi Paradox hasn't been "dissolved" in any way. It's a response to the
idea that the universe is teaming with life. The paradox remains unchanged
until we find a credible signal, or we create life in a lab under naturalistic
conditions.

~~~
thaumaturgy
This is addressed in the paper.

They use Bayes to update their estimates based on the lack of evidence so far
(which is, itself, evidence for lack of advanced stellar civilizations).

It has been dissolved in that they've pointed out a fundamental error in the
logic that leads to the paradox, and have used statistics and a review of
available literature to illustrate this error.

~~~
TheOtherHobbes
Absence of evidence isn't evidence of absence - especially not when dealing
with entities and civilisations about which we not only know nothing, but
about whose properties we can barely speculate.

The only thing Drake can possibly estimate is the number of civilisations
similar enough to our own to be recognisable.

There's an assumption that every civilisation will pass through a stage where
can recognise it - but of course there's no good reason to be confident this
is true.

So in fact the L term is unknowable.

There's also the fact that not all civs will transmit, but some would be
visible to better spectroscopic tools. Generally, as our technology evolves
you would expect our detection skill to increase too.

This isn't included in the original equation.

~~~
Jach
> Absence of evidence isn't evidence of absence

Yes it is. You may be confusing 'evidence' for 'proof', but here's a proof
that absence of evidence is indeed evidence of absence. (How much? That
depends.)
[http://kim.oyhus.no/absence/index.html](http://kim.oyhus.no/absence/index.html)

------
s-shellfish
The Fermi Paradox, to me, is more a philosophical question about the
destructive nature of humanity, than it is actually talking about alien
civilization. Points of note are 'what is the bottleneck to traveling outside
of the space we inhabit?'. Why does one ask the question 'why don't we see
life everywhere?'.

Lately, some of the time I see this as a metaphor for 'what is the dilemma
with broadening horizons?'

There could be alien life, there could not be. It's interesting to think about
for a while but sometimes I think it is talking about something deeper than
the existence of aliens and outer space. Philosophical question about the
nature of existence.

------
sebringj
The laws of physics are not localized to earth and yet we see life on earth
among countless other possible earths with extreme immense distances between
them that light (communication) takes thousands if not millions of years to
reach. We see life evolving in the heat vents at the bottom of the ocean along
with entirely different paths of evolution to create an eye. Why is this a
mystery we have not seen intelligent life? Earths may be frequent and life as
well but intelligent life capable of communicating through light AND close
enough to communicate may be very very rare. After all, we are only here
because the dominant dinosaurs with tiny brains died out changing the rules.
In other words, I don't know but intelligent life isn't necessarily the normal
end game.

~~~
Klathmon
But part of the paradox is that "universe time" is so monumentally longer than
"human time".

Even if only a fraction of a fraction of a fraction of all life make it to
what we could call "intelligence", then those beings are most likely millions
or billions of years "ahead" of us, or won't be intelligent for millions or
billions of years from now.

At those timescales, even things millions of light-years away are "within
reach" of some kind of contact, unless there is something making it impossible
(like all intelligent life snuffs itself out given enough time).

This is easily one of my favorite things to just think about.

~~~
gowld
you don't need to "snuff out" life to make it undetectable to us, you just
need something that prevents life from getting complex enough for interstellar
travel. It's quite plausible that live ebbs and flows (like it has on Earth),
but never gets large enough and powerful enough to be detected at remote
locations subject to inverse-square signal dissipation.

------
pfortuny
Wilmott has a simpler way of explaining it: in a magician’s show, what are the
odds that he guesses your card right?

The question makes no sense because there is no plausible model: he may
willingly decide to guess wrong, for example, or the trick may consist in
making you forget the card or any other thing.

Assigning probabilities without a real model is just hubris, no more.

~~~
whatshisface
You could go to ten thousand magic shows and write down the result of the card
guessing each time. Then, based on those probabilities, you could win on
average a betting game between audience members about the results of future
tricks. No model required.

------
jhallenworld
I find the argument that advanced growing alien civilizations would construct
"Dyson Swarms" pretty convincing. These structures have the huge advantage
that no new physics is required- we could start building ours now with today's
technology.

They would look like infrared point sources. Sadly none detected yet:

[https://medium.com/starts-with-a-bang/dyson-spheres-the-
ulti...](https://medium.com/starts-with-a-bang/dyson-spheres-the-ultimate-
alien-megastructures-are-missing-from-the-galaxy-447f5f87c2dc)

~~~
bena
Why do you find that convincing?

He pretty much handwaves away one of the biggest problems: material. Saying
"we'll harvest Mercury" is such a "world hunger solution"* that I can't take
anything further seriously.

*World hunger solution: A solution presented in such a way to seem simple but instead hides many more problems just under the surface. e.g. The best solution to world hunger is to simply give everyone enough food. True, that would solve the problem, but we don't know how to do that.

And saying that "advanced civilizations" will be able to do it is pretty much
going into the Giorgio Tsoukalos camp. "Aliens" is not an answer. It still
ignores the how. What are the costs of harvesting an entire planet? What are
the energy requirements to send mining equipment there, mine the planet, and
ship the materials back here to be processed into something useful?

Why do you assume that that level of technology will be cheap and readily
available in the future?

~~~
jhallenworld
It's convincing in that it seems physically possible. Even better, it's
falsifiable: look for infrared point sources.

Also, what options do you have if you're out of real estate? There is no
faster than light travel. Slower than light interstellar travel is certainly
not going to be cheap or easy. Of course the other option is for your
civilization to stop growing, but who knows if all aliens would go for that.

~~~
bena
No infrared point sources just means it's not likely there are any Dyson
spheres.

It doesn't tell us why there are no Dyson spheres.

> Of course the other option is for your civilization to stop growing, but who
> knows if all aliens would go for that.

You act like this is a choice. What if it's not a choice? What if the initial
cost to build a Dyson sphere is too great to overcome? Whether in time,
material, energy, or another thing. What if it's just not feasible?

Where does that leave you?

You've basically reframed your statement. You find it convincing because you
think it seems physically possible. But how? We're just getting to Mars and
you think a significant mining operation on an alien planet to be something
we're technologically capable of.

We've skipped straight to 3) Profit and forgot to flesh out step 2).

~~~
eloff
It's not profitable yet, or someone would already be doing it. It's something
that can be done on small, incremental scales. You don't need to mine a whole
planet, that's a strawman. You don't need to build the entire thing, just some
solar panels floating in space an attached to something useful (e.g. our
communications satellites) fit the bill. It gets more effective the more
industry you have in space - we have none so far.

There's no reason to think we won't reach that level of technology - assuming
we have a demand for space industry for some reason, like running low of key
materials on Earth, or a population that keeps growing.

You're basically just doing that same thing as the OP, claiming "nuh uh"
without backing that up either. To which I say "uh uh".

~~~
bena
It's an assertion without evidence.

You claim there's no reason to think we won't reach that level of technology.
What's the basis for that claim?

> just some solar panels floating in space an attached to something useful
> (e.g. our communications satellites)

You realize that a lot of our communications satellites already have solar
panels attached to them, right?

And you do realize that a Dyson anything is an engineering project that far
exceeds anything we have yet attempted. If your plan begins with strip mining
a planet 48 million miles away with an army of self-replicating robots, you've
obviously skipped a few steps of the process.

Using "science-y" words to describe your pipe dream doesn't make it any less
of a fantasy.

I mean, we're still wondering if we can make a car drive itself reliably. That
we may not be able to overcome some very basic limitations. And all of a
sudden we get to assume we can build a probe that can travel to Mercury, mine
it, process the raw material into something useful, assemble those materials
into more probes, panels and habitats, then place those bits into orbit around
the Sun in a way that it won't get smashed by other satellites, fly off, or
get pulled in.

Reducing those concerns to "nuh uh" isn't doing you any favors. You're simply
refusing to engage. You're asking skeptics to prove that we will never reach
that level of technology rather than answer the question of why do you think
we will. You're the one with the actual claim here, back it up.

~~~
eloff
>You realize that a lot of our communications satellites already have solar
panels attached to them, right?

Hence why I said (e.g. our communications satellites), which in English means
communications satellites are examples of useful things with solar panels
attached "floating" in space...

> And you do realize that a Dyson anything is an engineering project that far
> exceeds anything we have yet attempted. If your plan begins with strip
> mining a planet 48 million miles away with an army of self-replicating
> robots, you've obviously skipped a few steps of the process.

I already mentioned that's a strawman. A Dyson swarm is an orbiting collection
of artificial satellites, orbiting the sun. It captures all or a good deal of
the energy radiating away from the sun - but it's built incrementally and a
single satellite can be the start of a Dyson swarm - so we have the tech now.

> You're asking skeptics to prove that we will never reach that level of
> technology rather than answer the question of why do you think we will.
> You're the one with the actual claim here, back it up.

You're deluded if you think you can get random people on HN to defend their
statements to a level you'd be happy with. Honestly I don't have the time, and
even if I did _I don 't care_.

But since you've got me to engage this far, here goes: we have the tech to
build solar powered satellites and launch them into orbit around the sun. So
we could start building a Dyson swarm today.

The reason we don't is because it's very expensive, and we suffer a chicken-
and-egg problem. There's not much demand for industry in space because we
don't build anything in space. The inputs and outputs would have to come from
and return to Earth. There's no demand for habitations in space because
there's no supporting infrastructure, food, water, jobs, etc. Not to mention
the long term health effects of living in space seem problematic to say the
least. But it's not unforeseeable that something could change that situation,
be it overcrowding on earth, demand for space mining, demand for zero-g
manufacturing, space war, government programs, etc.

~~~
bena
> Hence why I said (e.g. our communications satellites), which in English
> means communications satellites are examples of useful things with solar
> panels attached "floating" in space...

What you actually said was:

> You don't need to build the entire thing, just some solar panels floating in
> space an attached to something useful (e.g. our communications satellites)
> fit the bill.

Where the implication is that we'd attach these solar panels to something
useful and that an example of something useful is the communication satellite.
Whereas you wanted to infer that communications satellites were the entire
enchilada, a solar panel attached to something useful. Which is also a bit
disingenuous as the panel is a part of the satellite, the power source, not an
add-on. Which pretty much led to the confusion.

> A Dyson swarm is an orbiting collection of artificial satellites, orbiting
> the sun.

That's a reduction as to what it actually is. A big part of the Dyson
architecture is to capture and use the energy provided by a star. Simply
having a satellite orbiting the Sun would not fit the bill.

And a space based solar power satellite does not exist. Because it's more
expensive to launch and implement than it would return. All current solar
power on satellites provide enough power to power themselves. That's it. What
you are asking for is something different.

NASA themselves says that a SBSP satellite is decades away at the earliest.
And any proposition to be speculative at best.

And yes, necessity is technically the mother of invention but it can't change
the laws of physics. It can't change the cost of what's necessary.

> You're deluded if you think you can get random people on HN to defend their
> statements to a level you'd be happy with.

This is just a dodge. You've done nothing but say "It's not unforeseeable" and
"It's inevitable". You haven't actually provided a reason as to why you think
that. I'd be happy with anything more than a handwave in the general direction
of the actual issues facing building a Dyson swarm.

> Honestly I don't have the time, and even if I did I don't care.

You do care, you just don't really have any answers besides the blind faith of
"technology". Which is no better than blind faith in anything. Believing
technology will get better doesn't actually make it better.

------
madeuptempacct
As of today, we wouldn't be able to detect a same-tech-level civilization even
at the closest star with the amount of effort we have given this, so there is
no paradox in my mind.

~~~
roywiggins
All it takes is one sufficiently early civilization that goes full Neumann-
replicator and decides to colonize every system it can for them to have
already arrived here long ago. The fact remains that it seems like they
didn't, unless they were very careful boy scouts and left no trace.

~~~
nv-vn
There are so many variables. For example, if they can't travel faster than the
speed of light, they might not even think it's worth colonizing. They could
also be on scales vastly different from our own, as microbes or as planets. We
wouldn't even know what to look for in interstellar communications, let alone
have the ability to make sense of anything they send. Our entire "search" has
come with the assumption that alien life is going to communicate with radio
waves, use sight (in the same range as our own), be similar in size to us,
etc.

~~~
roywiggins
It just takes one weirdo civilization that decides to put up Ozymandias-style
monuments to themselves everywhere- they don't even need to do it themselves.
They can fire off a few Von Neumann probes and let them do the work to carve
Mount Rushmores into every rocky body they can find.

It's not much weirder than things humans get up to, and if spacefaring
civilizations that can build such probes are common at all (even if short-
lived), you might expect at least one of them to have initiated such a project
and been successful enough to have built a giant "we wuz here" radioactive
pyramid on the moon. Evidently, none of them did- and depending on how many
there were, this is either unsurprising or deeply unlikely.

------
thomk
I know everything I know about the Fermi Paradox from this video (and part 2):
[https://www.youtube.com/watch?v=sNhhvQGsMEc](https://www.youtube.com/watch?v=sNhhvQGsMEc)

That YouTube channel is awesome by the way. Say goodbye to the rest of your
afternoon!

------
DaveInTucson
For me, the problem with the Fermi paradox is that we only have one poorly
understood and incompletely documented example of a planet with intelligent
life from which to draw conclusions. Beyond that:

* How many habitable planets are out there? We're just now starting to get data on this, there might be a lot

* Of those, how many develop life?

* Of those that develop life, how many develop intelligent life?

* Of those that develop intelligent life, how many advance to the point where they're capable of interstellar travel? How many are interested in interstellar travel?

* What if FTL travel is simply not possible? STL interstellar travel could basically be a one-way trip. Maybe most (or all) alien civilizations are unwilling to explore beyond a few light years.

* What is the lifetime of a space faring civilization? maybe all the alien civilizations just died out before they explored very far.

~~~
Klathmon
Widen your idea of life.

What if another species has figured out a way around death? What if the idea
of a single "life" isn't really a thing, and alien lifeforms instead live as a
single "consciousness" among them all forever alive. Then the idea of spending
millions or billions of years traveling around the universe isn't necessarily
a "one way trip".

------
neals
So, my fellow HN dreamers... Would you rather be the first or the last
civilization in existence?

~~~
lainga
First, so I can show up in the 3rd or 4th installment of a future
civilization's video game franchise as an "Ancient One" and speak in
hexameter.

~~~
vkhorikov
Also first so I can introduce a Reaper and make sure no other civilization can
advance too much

------
tjradcliffe
"Maybe people intuitively figured out what was up (one of the parameters of
the Drake Equation must be much lower than our estimate) but stopped there and
didn’t bother explaining the formal probability argument."

There's no "intuitively" about it. We know from the data available that the
probability of machine-building general intelligence of the kind that is
unique to humans on Earth is fantastically unlikely to arise. It depends on a
confluence of completely unrelated selective pressures: one on tool-making,
one on social cooperation, and one on continuous mate competition/selection.
There is good evidence that all of those forces are important to specifically
human--not dolphin or bird or whatever--intelligence on Earth, and without any
one of them we'd still be fairly handy monkey-creatures banging rocks around.

As well as a theoretical understanding, we have empirical data. We can ask,
"If something is at all probable how many times will it have evolved on
Earth?"

Eyes, for example, have evolved independently multiple times, based on
differences in retinal biochemistry. Wings and fins and legs have also evolved
many times across an incredible diversity of species. This tells us that
things that are easy to evolve have evolved multiple times in Earth's history.

Specifically human, machine-building intelligence has evolved exactly once.
This is strong evidence that it has an enormously low probability.

Once you've realized that one of the parameters in the Drake equation is
incredibly small, the Silent Universe is no longer surprising. And both
empirically and theoretically, the probability of evolving specifically human,
machine-building intelligence is incredibly small.

However, I have never met anyone enamoured of Fermi's Paradox who gives any
credence to this, which is why no attempt to resolve the paradox will ever
have any effect on the discussion. This is in general the case with so-called
paradoxes: no matter how many times they are clearly and simply resolved,
people who want there to be paradoxes will pretend the resolution doesn't
exist, or will deliberately misrepresent it as a non-solution. Or they will
present some other non-solution as more compelling, even when the solution
presented makes those non-solutions unnecessary.

------
jasonkolb
I've been listening to the "3 Body Problem" trilogy by Cixin Liu. I'd highly
recommend it because not only is it some mind blowing sci-fi, but it also
contains one of the most interesting solutions to the Fermi paradox that I've
ever seen. I don't want to give anything away because the books are a real
treat if you're like me, but the explanation is based on game theory and
actually makes a ton of sense.

Highly recommended.

~~~
garmaine
Try the Revelation Space series for a better, and earlier take on the idea.

The 3 body problem is masquerading as hard SF but isn’t. The author totally
misunderstands physics, astronomy, and space faring technology. I hated the
books, personally, and don’t see why they are so hyped.

------
ared38
> Why didn’t anyone think of this before?

Anyone that's read even the intro section of the Fermi paradox Wikipedia page
already has: "There have been many attempts to explain the Fermi paradox ...
suggesting that intelligent extraterrestrial life is extremely rare". The
paper just formalizes that by demonstrating we can arrive at low enough
expected numbers of aliens (namely 0) with reasonable inputs to the drake
equation.

> Imagine we knew God flipped a coin. If it came up heads, He made 10 billion
> alien civilization. If it came up tails, He made none besides Earth.

This occludes a lot more than it illuminates. Although the end section of the
paper uses the bayesian inference Sniffnoy hinted at, the graphs SSC used (and
his analysis of the papers results) come from the earlier section of the paper
that still use the "chance of aliens per star" model. Even the bayesian part
merely refines this probability based on observations; it's hardly "the wrong
way to think about it" as SSC claims.

------
thaumaturgy
The actual paper, linked from the top of this article, is very readable and
I'd recommend taking the time for it.

In summary, the traditional approach to the Drake Equation has been to assign
fixed values to each polynomial, sometimes an ass-pull and sometimes based off
of best estimates from the observable universe. i.e., "0.1 x 0.1 x 0.1 x
0.1..."

What these researchers did instead is try to account for the uncertainty of
various parameters. They gave each polynomial values in the range of [0, 0.2]
for example, ran Monte Carlo simulations on that, and came up with an empty
universe 21.45% of the time.

To put it another way: we consider it a certainty that some worlds will bear
life, and a certainty that some of that life will develop into intelligent
civilizations, and a certainty that some of those intelligent civilizations
will explore their local system, and a certainty that some of those explorers
will develop into massive hyper-intelligent, technologically-advanced, galaxy-
spanning species. But we haven't got enough information to be certain about
any of those within any reasonable order of magnitude. The probability of any
one of those may in fact lie so close to 0 that it solves the Fermi Paradox.

FWIW (and it's worth basically nothing), this has been my preferred solution
to the Fermi Paradox for a long time now, and it's nice to have this paper to
cite when it comes up in the future. I figured that it took Earth 4.5 billion
years to produce humans, and humans are only barely space-faring at this point
and I'm not certain we'll ever make it out of our solar system. Countless
species have appeared and gone extinct in the meantime. It seems far from
certain, to me, that evolution necessarily leads to intelligent life, and if I
remember right, the latest thinking from evolutionary biologists supports this
-- suggesting that modern human intelligence is largely accidental, rather
than a byproduct of evolution.

The age of the universe would seem to suggest that there's been time for at
least a few other worlds to develop intelligent life even at very slow,
unlucky paces, but then again, at astronomical time scales the universe has
been too violent up until recently to foster that kind of development.

The Fermi Paradox seems to have captured a lot of interest from people who
like sci-fi and want to think about all kinds of fantastic ideas on why we
appear to be alone. Is there a Great Filter? Is this a simulation? Are we in
some kind of super-advanced stellar nursery? It's like nerd sniping
([https://www.xkcd.com/356/](https://www.xkcd.com/356/)) for a particular sort
of nerd.

~~~
jerf
I have no idea why, as I write this, the parent is greying out. It's the only
reasonable comment on the article as I write this.

I know you're really not supposed to tell people they need to read the article
on HN, but the paper underlying the article may be the least understood
primary source I've ever seen posted to Hacker News. (This beats out the
previous record holder, monad tutorials based around an actively incorrect
metaphor.) This is _not_ just a standard reiteration of the Fermi Paradox with
somebody's new numbers pulled out of the air. It is a legitimately interesting
analysis of the problem as a whole.

Read the article and/or the underlying paper, _carefully_ , before just
reciting the Standard Cant Against the Fermi Paradox, OK? (And downvoting the
only person giving a decent explanation of it.) The Standard Cant is
encompassed and superseded by the paper in question, with mathematics.

~~~
reordering
I know I’m not supposed to pile on, either, but... how on earth is your parent
_still_ at the bottom?

If you accept this paper’s conclusions, all the rest of the discussion here is
about science fiction. There’s nothing about the theory or evidence that
demands either explanation or refutation.

And the one person who actually lays that out is being downvoted for, what,
being too explainy? This is bizarre.

------
matte_black
What if life is actively being destroyed by some powerful civilization? For us
life may be some beautiful miracle worth cherishing but perhaps there’s a
brutal species out there with no greater regard for it than the weeds growing
in our gardens.

On an intergalactic timescale humanity has only been around for the blink of
an eye. So probably not long enough for a civilization that operates on cosmic
scale heartbeats to have noticed us yet. When they do though, they might cast
off a gamma ray burst in our direction and sentence us to death, checking back
to see the carnage several lightyears later, just like they have done with so
many other planets teeming with life.

They have made a critical error though: they are entirely too late. They
should have done it when we were little more advanced than the beasts who
graze on the grasslands. We are now on the brink of exponential technological
advancement. By the time they fire off their attack we’ll see them coming and
have time to prepare. They will have given away their position, and by the
time they look for the dust of what was once our home they will find a hundred
new starships and space stations, expanding rapidly away but a great portion
moving closer in an ominous pattern.

Then they will realize what they have done. This time, they messed with the
_wrong_ species. And then our message will arrive.

As they look at each other right to left and left to right with some alien
expression of panic, a malevolent vibration will carry the voice of humanity
unified in a way that it has never been before. This will not be the peaceful,
optimistic greeting of our Voyager. This will be something unmistakable in
it’s intent, something that can only be promised by a civilization that’s been
killing itself and nearly killing it’s own planet for all it’s existence, and
now thirsting for revenge with a rage handed down from generation to
generation. Whenever these beings sleep, if they must sleep, they will be
haunted with echoes of our message, still ringing in their heads loud and
clear: _" We’re coming for you—motherfuckers."_

------
yedawg
We are here, so why can't aliens exist, right? I don't think it's as simple as
the drake equation suggests. There are trillions of variables that life on
earth has had to overcome with relative success. Even this is abstract and is
in turn subjective. I speculate that if we repeatedly redefine our assumptions
on how unlikely it is for life to arise in our part of the universe, we still
only have a potential baseline for life in the milky way; this is again skewed
by our position in the solar system and cannot be reasonably accounted for by
an algorithm. (We don't know what we can't test)

------
framitz
Does the Drake equation model the universe to provide any real insight into
the Fermi Paradox? Even if it does, only a few factors have enough data points
to allow the ranges in the learned SDO analysis to strongly illuminate the
question, “Where’s ET?”

We slowly make empirical progress on the ranges. For one thing, we now know
how many stars in the immediate neighborhood have planets: the vast majority.
We now know that the prospects for water/organic based “life” look pretty good
in our neighborhood: there are in the range of half a dozen prospects in our
solar system. We might nail that one down a bit more within a few decades. We
just need one hit on Enceladus, Europa, or Mars.

Until contact is confirmed, it seems the question comes down to two big
problems: (1) It took 3-4 billion years for life on earth to evolve from first
replicating molecules to “intelligent life.” Our species is ≈ 200,000 years
old. That represents 1/23000th the age of the earth.

(2) We have had “radio” (radiotelegraphy) for a little more than one century.
That represents 1/46 millionth the life of the planet.

Assuming humans survive for quite a while longer, what are the chances that
another species—say, within 1000 light years of us—will be using “radio” (EM
communication) at the same time? Even if our two species each survive a
million years, the chances we appear at the same time are slim. A million
years represents 1/4600th the life of our planet.

On a positive note, there are in the range of 16 million stars within 1000
light years of earth.

The Fermi Paradox presumes much: intelligent life is destined to evolve on
suitable planets; intelligent life survives the filters (my doomsday money is
on human pollution, ye olde shite problem); EM communication or star travel is
a logical outcome of intelligent life. All of these seem a bit dubious to my
limited mind.

On the other hand, almost by definition, a starship is immortal. If humans
ever achieve a viable industrial infrastructure, at say, Jupiter, we will have
already overcome many of the obstacles of traveling to Alpha Centuri. A self-
contained, self-repairing, self-propulsing “vehicle” has to avoid collision,
of course.

Here, my money bets first contact will be, or has been with machines.

------
wilg
Question for someone smarter than me: is this a similar argument to this[1]
1985 paper (referenced by Wikipedia in the "criticism of logical basis"
section[2] on the Fermi Paradox article)?

[1]
[http://adsabs.harvard.edu/abs/1985Icar...62..518F](http://adsabs.harvard.edu/abs/1985Icar...62..518F)
[2]
[https://en.wikipedia.org/wiki/Fermi_paradox#Criticism_of_log...](https://en.wikipedia.org/wiki/Fermi_paradox#Criticism_of_logical_basis)

~~~
vlasev
No. This 1985 paper you reference talks about a logical argument for why there
is no paradox, whereas the discussed paper is talking about how the
uncertainty in the parameters is enough to yield something that is not a
paradox.

------
lisper
TL;DR: expected values can be very improbable. The expected value of a
Powerball ticket is >0, and in fact by increasing the amount of the prize the
expected value can be made arbitrarily large. But the probability that the
actual value will be >0 is very nearly zero. And most importantly: that
probability does not change as the prize money (and hence the expected value)
increases. No matter how big the prize is, you will nonetheless almost
certainly not win.

------
microtherion
Previous discussions here:
[https://news.ycombinator.com/item?id=14686687](https://news.ycombinator.com/item?id=14686687)

And here:
[https://news.ycombinator.com/item?id=17302924](https://news.ycombinator.com/item?id=17302924)

------
gmuslera
The Fermi Paradox makes me remind of
[https://xkcd.com/605/](https://xkcd.com/605/) . Would that extrapolation look
normal for an alien or for someone of a radically different culture? Oh, even
a child from our culture would argue that you just can't marry twice not each
day, but for total outsiders it won't be so obvious and even some may think
that it should happen.

We are outsider ones in this Fermi Paradox extrapolation. We are very far from
being able to do interstellar travel, specially in scale, tripulated, or
thinking in some way of colonization, even for our closest star system. Like
with the weddings, we are extrapolating without knowing anything about how it
is really in practice interstellar travel and colonization, specially in big
scale.

And more than just about physics, it assumes more things about intra/inter
alien culture. They must expand as much as they can, and they must do visible
for everyone things (dark forest? nah), and interstellar travel/colonization
is possible and desirable... those, besides the Drake equation, are the axioms
of it. And they may not be true or at least give another big factor to
consider in the Drake equation.

Not knowing is not equal to knowing that not. You must leave space for things
that you don't know that you don't know.

------
e67f70028a46fba
_> If this is right – and we can debate exact parameter values forever, but
it’s hard to argue with their point-estimate-vs-distribution-logic – then
there’s no Fermi Paradox. It’s done, solved, kaput._

this makes no sense at all: whether or not there is a fermi paradox absolutely
depends on the parameters "we can argue about"

~~~
OscarCunningham
Perhaps it be accurate to say the _given our current knowledge about the
parameters_ there's not currently a Fermi paradox, but if we gained more
information about the parameters then a Fermi paradox could arise in the
future.

~~~
rad88
But nothing at all is really known about "length of time for which such
civilizations release detectable signals into space". It's somewhere between a
few decades or so and 10 billion years?

~~~
OscarCunningham
Sure, which is one of the reasons why we don't currently have a Fermi paradox.

~~~
EthanHeilman
To me the Fermi Paradox isn't really a paradox it is framework for thinking
about the problem. This research fits into that framework and provides an
interesting new argument that the great filter is more likely to be in our
past rather than our future.

------
Falkon1313
The real problem is that it's built on a foundation of assumptions, all of
which are completely anthropocentric - more specifically, that foundation's
cornerstone is based upon the behavior of humans in developed countries during
the 20th century. Especially repressed aggression. It really tells us a lot
more about ourselves than about aliens.

"If aliens exist, they would send tight-beam radio communications on this
exact frequency (because that's the one that we'd choose!), in a format that
we could recognize as an attempt to communicate (probably English, because we
all speak English! Or maybe Morse code), and keep spending resources doing it
for however many thousands or millions of years it took for us to notice."
Even we don't even do that. Most of our radio transmissions now are short-
range bluetooth, wifi, cellular, or satellites pointed at the planet. Our
broadcast signals, though some might be strong, are attenuating in cubic space
and all mixed together containing all channels and stations - white noise and
static at best. We just assume that if they're not speaking our language in
our formats, they're not really civilized/advanced.

"If aliens exist, they would have conquered the entire galaxy by now, because
that's what we'd do!" I've lived here for years and haven't tried to conquer
my neighbors and have no intention of doing so. Yet we assume any
sufficiently-advanced aliens must be violent.

"If we couldn't conquer it straight away, we'd at least send self-replicating
robots to claim every planet! So if aliens existed, of course they would have
done that!" They may not be self-replicating, but any of us could buy drones
and send them to claim undeveloped plots of land that we couldn't use. Yet we
don't. It'd be pointless. But we assume any sufficiently-advanced aliens must
be selfish.

"We've been ripping every resource out of the planet as fast as we can and
polluting as much as possible to maximize profits and shareholder value. If
aliens exist, they would do the same and even go as far as creating Dyson
spheres!" Well yes, we do destroy our environment. But some of us have
realized that it is a bad idea to do that and we should probably ramp it down,
rather than go to the full extreme of destroying our entire solar system. Yet
we assume any sufficiently-advanced aliens must be greedy.

I don't really think it's a paradox mainly because I don't have that
underlying assumption that all aliens must act like the noisiest, greediest,
most violent and self-absorbed humans of the 20th century. Perhaps the paradox
is that we expect all civilized life in the rest of the universe to be as bad
as the worst of us, and it's just not, and we don't have an explanation for
that yet.

------
based2
[https://en.wikipedia.org/wiki/Gamma-
ray_burst](https://en.wikipedia.org/wiki/Gamma-ray_burst)

------
smcllns
Several threads here mention the problem with sample size of one. That's true
that it makes it very hard. But there's some interesting extra information we
can also extract from this one sample: Life on earth either 1) developed
naturally from physics or 2) arrived here from another place. If #1, it means
life will develop in other places in the universe - and can do to the extent
of transmitting electromagnetic waves. If #2, it already exists/existed
elsewhere and was clever enough to send itself elsewhere and evolve to send
electromagnetic waves.

From all the life that has evolved on earth, from bacteria to trees (to clever
octopus) to humans, a very small percentage of that life evolved to create a
signal that is detectable far away (humans/radio waves).

I don't really know how to factor this into the paradox, but based on the
above, it seems so possible to me that life widely exists but it is simply a
miniscule % that has evolved in such a way to use electromagnetic energy in a
way that is detectable by us today.

