Fermi Paradox becomes an intellectual “thing” in the early 1980s?

[Arkenfolm]

Even if the universe is teeming with life forms, is there any statistical guarantee that any of them would be technologically advanced enough to reach Earth? How do we know that homo sapiens aren't the smartest beings in existence?

(Serious questions, not rhetorical.)

I think the idea of a "Stone Age Universe" where humans are among the most technologically advanced (or maybe a bit scarier, THE most advanced) is far too underexplored in discussions of the Fermi Paradox, possibly because it's more soft-sciences focused since it's about the roots of civilization and how a civilization progresses from "Paleolithic" to making a big enough impact on the universe via Dyson swarms and interstellar colonization.

I think it's highly likely, but also one we aren't likely to be able to say much given we can't really say what an average biosphere looks like.

Have a huge moon due to tidal action which may be important to the foundation of life 3) Have large amounts of carbon which should be pretty common but might rule out some planets. 4) Have an active magnetic field to avoid having its atmosphere stripped which is actually quite rare. IIRC Earth is the only rocky planet to have one.

I'm not convinced that either the large moon thing or magnetic field thing is necessarily a huge issue or even that rare given our sample size of exomoons is practically nil outside of some rogue planet moons (which might just be small brown dwarfs and their "planets"). Granted, this is a big problem in general when discussing the Fermi Paradox although I think a lot of the criticism based on this line of thinking is overblown since there's a lot we DO know and can reasonably assume. Hell, maybe the ideal place for life is a gas giant moon, that certainly has tides and a magnetic field.

Similarly, the Galactic Center has the majority of mass in our galaxy so even if it's far less likely to host life, there's so many planets that enough chances for abiogenesis and evolution should eventually produce the radiation tolerant life necessary for survival. Although I suppose the frequency of mass extinctions would be detrimental to complex life. You could probably calculate that by taking the number of supernovae and GRBs in a galaxy's core and comparing it to Earth's history of mass extinctions, at least the ones suspected to be caused by GRBs.

 

[dwkelley]

Even if the universe is teeming with life forms, is there any statistical guarantee that any of them would be technologically advanced enough to reach Earth? How do we know that homo sapiens aren't the smartest beings in existence?

(Serious questions, not rhetorical.)

As expanded in a previous answer, this *is* one possible answer to the Fermi Paradox: we are currently the most advanced civilization in the galaxy.

The flaw in this is that we shouldn't be first. Our sun is actually a 2nd generation star IIRC - that is, since the galaxy formed, at least one generation of yellow stars has born, lived, and died before our sun came into existence. That's billions of years for another system to bring forth life capable of interstellar travel.

Now, how long will it take to explore the galaxy? Assume about 200 billion stars in the galaxy at any one time (that's 200,000,000,000). Going about 1% of the speed of light (faster than we have ever done, but certainly technically if not financially feasible today), we could reach Alpha Centauri in about 400 years. So suppose we send two self-replicating probes out in opposite directions. It takes 1000 years average for each probe to get to a target system, make two more probes and send them out (then the original probe stays put and sends reports back to the mother planet). So, in 2000 years you've got a probe at 4 systems, 3000 years 8 systems, 4000 years 16 systems, and so on. In short, in "X" thousand years you've got a probe at 2 to the power of X systems. So, even allowing for some accidental overlap, it should take less than 40,000 years to put a probe at EVERY SINGLE SYSTEM in the galaxy. That doesn't mean any alien survey probe should be obvious to us mere Earthlings today, but it does mean that (at least one) alien civilization should already be aware of us: 40000 years for the probe to arrive in our system, then less than 40000 years for the fact there's a blue-green planet present to make its way back to their homeworld - and that's only if the other civilization is on the other side of the galaxy from us.

There are many alternative explanations given - civilizations always reach a technical singularity before serious space exploration begins, or always annihilate themselves, or life is really much harder to generate than we think, are among the more popular ideas. But until we have the technology to really look (with sufficiently high-powered telescopes) at nearby yellow stars, all we can do is speculate.

 

[Aisha Clan-Clan]

He scariest thing about a dark forest hypothesis is it’s internalisation of Mancunian capitalist ideology as natural. How old is Mutual aid: a factor in evolution?

Eh, it makes sense to me. The universe literally has limited(if ALOT) amounts of atoms/protons for resources or energy so you'd get zero or negative-sum thinking at some level.

 

[Arkenfolm]

Eh, it makes sense to me. The universe literally has limited(if ALOT) amounts of atoms/protons for resources or energy so you'd get zero or negative-sum thinking at some level.

The key problem is that it's impossible to hide from a civilization capable of sterilizing other planets from light years away so while there's no reason to broadcast "Hello, we are the good people of Randomplanet 3, here's our policies on expansion and trade and blueprints to our tech!" to the universe, there's no reason to hide either since you can't. To take Earth as an example, any aliens capable of destroying Earth will know Earth has a technological civilization the minute they can see Earth as it was around 1850-1900. Only way to hide is basically enforced primitivism or deliberately shaping industrial development so it's as low-scale and minimal as possible in terms of signs like radio waves, greenhouse emissions, and surface lights.

It would actually be interesting and plausible if a movement, however fringe, arose based around this theory. Likely it would have if the idea had been around in the 60s/70s. I'd imagine they'd fuse with radical environmentalism and primitivist movements but be more pro-technology in the sense they would want to build low-impact but high-tech utopian communities like subterranean and deep sea cities to better mask emissions and of course very strict birth control and family planning (but not human extinction levels). I could see some serious UFO religion elements like Raelism but there's more than enough of interest to more typical radical environmentalists and primitivists that they might find the movement's rationales of interest.

 

[GeographyDude]

Dark Forest theory: A terrifying explanation of why we haven’t heard from aliens yet

The Fermi paradox asks us where all the aliens are if the cosmos should be filled with them. The Dark Forest theory says we should pray we never find them.

bigthink.com

The Dark Forest Theory: The Reason Why We Shouldn’t Be Looking for Aliens - SFCritic

A part of space exploration has always been dedicated to finding extraterrestrial life. After all, in such a big universe, it’s highly unlikely that we’re the only ones living in it. However, aside from a few mystery radio waves and planets that could sustain life due to the presence of water in...

www.sfcritic.com

The Dark Forest Theory: A Grim Answer for Where All the Aliens Are

The question of whether we are alone in the universe has swirled around our consciousness since as long as we were able to

mysteriousuniverse.org

With the first, I had a hard time getting a clean download. I read pretty much the entire second.

So, the “safest” course of action is to assume this hyper-aggressive, forward military stance ? ?

It’s poor poker play.

By bending our society in this direction, we may bring about the very outcome we fear. A better alternative might be a strategy of Non-Provocative Defense, which I think was most talked about in books for European countries during the cold war days (maybe a little in practice).

Basically, you’re better able to absorb a first strike and you’re less of a plum worth an easy conquer. And some of this will happen in the natural course of things as a tech society spreads out among several star systems.

And . . .

 

[GeographyDude]

We already practice active SETI, which I think is also called METI.

(although we probably shouldn’t)

 

[GeographyDude]

“ . . . to witness Sónar, a three-day festival dedicated to electronic music, art, and design. Something of a cross between a TED talk, Burning Man, and Coachella, . . . in 2018, the festival partnered with the Catalonia Institute for Space Studies and the nonprofit METI International to send a series of interstellar messages to Luyten’s star, a red dwarf about 12 light-years from Earth. Although red dwarfs are the most common stellar objects in our galaxy, Luyten’s star is remarkable for hosting GJ237b, the closest potentially habitable planet outside of our own solar system. . . ”

I’m kind of with you. I think we need a shit ton more public discussion before we do something like this.

 

[teg]

As expanded in a previous answer, this *is* one possible answer to the Fermi Paradox: we are currently the most advanced civilization in the galaxy.

The flaw in this is that we shouldn't be first. Our sun is actually a 2nd generation star IIRC - that is, since the galaxy formed, at least one generation of yellow stars has born, lived, and died before our sun came into existence. That's billions of years for another system to bring forth life capable of interstellar travel.

The counter-argument to this is that once you start listing all the things that have affected Earth in its existence - and there is no real reason to believe Earth has been particularly unlucky in that regard, as well as the potential fact that most Earth-like planets like Sun-like stars only have a comparatively short amount of time when they are capable of supporting complex organisms - I think it sounds potentially reasonable that filling the sky with civilization is actually a really time consuming process because not every Earth-like planet (which I personally believe are relatively rare) will develop intelligent life and then a space faring civilization.

 

[GeographyDude]

‘ . . . whether small groups of zealots should bypass all institutions, peer critique, risk appraisal or public opinion, to shout “yoohoo” into a potentially hazardous cosmos. Ćirković's book offers plenty of grist for discussion and consensus-seeking, before rushing to force a fait accompli on our children. . . ’

— sci fi writer David Brin (who also has a master’s in physics and a Ph.D in space science)

It’s basically the model of early, sloppy capitalism.

By God, we’re going to build this lead refining plant, the risks be damned. And if it later turns out that employees and neighbors have gotten poisoned, well, we’ll pay partial damages 20 years down the road.

 

[Kitiem3000]

It's weird that everyone just accepts that the drive to colonise the galaxy is a given. We aren't exactly jumping at the chance to send people to live on other planets. We only went to the moon to make a point to our enemies, and we are not in a hurry to go back. A majority of people disagreed with the moon mission at the time, and a majority isn't interested in spending money on Mars.

The X million years estimate assumes our eventual colonies are actively participating in establishing as many colonies as possible, but if there is no technological solution to make this easier or worthwhile, no anti-gravity, no ftl, no unobtanium, etc, then there is a good possibility the human race isn't going to colonise the entire galaxy. In fact it will most likely take an unbelievable amount of time to just spread throughout the solar system. Not because we can't, but because we can't be bothered.

Where are all the aliens? They are at home watching alienflix. Travelling to Earth is exhausting.

 

[Histor32]

Stunning.

With all the SETI we’ve done, we couldn’t even pick up TV leakage from Proxima Centauri ? ? Apparently not.

They use the 2.4 ghz band on alpha centauri... Lots of interference.

Actually given the extreme distances involved and the power requirements, let alone shielding, food, water, medical, etc. I would be surprised if others can or have gone beyond their nearest neighbors.

Another part of the paradox is finding life that is somewhat relatable to ours technologically. Fire up yiur TV from 30 years ago and it doesn't pick up today's TV over the air. Same with today's TV not picking up yesterday's channels.

Last but not least over the distances we are talking everyday communications should or would be indistinguishable from most background noise.

Now if we are talking sending very high power transmissions that stand out then this makes sense.

There is also the time required for said signals to get to another planet, plus the time for them to see it. Figure it out and respond with great we are on our way to coaume your planet

Note I belive there is lots of life in the universe. I also think that for civilizations that could be or are advanced enough for this sort of travel wouldn't even notice us for the most part.

We are no where near close

 

[GeographyDude]

And not that I think broadcasting our existence to aliens is by any means the greatest tech danger we face, or natural danger for that matter.

Richard Posner is a pretty brainy guy who is also a federal judge. One danger he talks about is particle accelerators such as RHIC. For example, a strangelet is a more compact form of up, down, and strange quirks. Sometimes it’s a self-limiting process; sometimes not. And at this point, I’m sure you’re realizing that, yes, a runaway strangelet process would be distinctly bad for planet Earth. One estimate was that there’s only a one in 2 billion chance of this happening. But, as someone pointed out, when we’re talking about the destruction of the planet, a one out of 2 billion chance is not automatically a gimme. Then the first group basically said, well shit, we only got one in 2 billion by fudging the numbers upward in a worse-case scenario type of thing. So, potentially a very interesting debate.

The “gray goop” scenario to nanotechnology is another topic which deserves more serious consideration.

And on the natural front . . . imagine if the Cornonavirus had 10%, or was something like Avian flu with even higher mortality? Once we put Corona back in the box, which we will, I really hope we settle for a steady eddie higher level of money for research into respiratory illnesses.

 

[Arkenfolm]

I’m kind of with you. I think we need a shit ton more public discussion before we do something like this.

There isn't really a risk for reasons I mentioned earlier. If anyone wants us dead, they already know of us and don't need some faint signal to be reminded of us. Consider how good we are at detecting exoplanets nowadays and even being able to message them, and then consider what a civilisation whose capacities include "able to kinetically bombard a planet from across a galaxy to the point it destroys all complex life" can do. If you want to exterminate rats, you don't need to hear the rat squeak to be able to decide to do something about it. There's many ways of finding out you have a rat problem other than hearing the rat squeak.

It should not be hard for a civilisation this powerful to be able to discover every Earthlike planet in the galaxy and monitor them for signs of sentience (i.e. lights at night, sudden changes in atmospheric composition and radiation, etc.), calculate the trajectory of the kinetic attack over the many, many years it will take, and then fire away.

The counter-argument to this is that once you start listing all the things that have affected Earth in its existence - and there is no real reason to believe Earth has been particularly unlucky in that regard, as well as the potential fact that most Earth-like planets like Sun-like stars only have a comparatively short amount of time when they are capable of supporting complex organisms - I think it sounds potentially reasonable that filling the sky with civilization is actually a really time consuming process because not every Earth-like planet (which I personally believe are relatively rare) will develop intelligent life and then a space faring civilization.

From my understanding, if you changed the ratio of a few elements like iron and oxygen during Earth's formation you should have a faster Great Oxygenation Event by a few hundred million years (less iron for the oxygen to bond to) and thus have more opportunities for a Cambrian Explosion earlier on (aerobic respiration might be a prerequisite for complex life) leading to more opportunities for sentience. Species diversity remained low until 600 million years ago, which means Earth wasted perhaps 3.5 billion years after life first appeared to evolve down the path toward sentience.

Sun-like stars actually aren't that bad for life, since a planet at the outer edge of the habitable zone (or just outside it) might evolve microorganisms via lithopanspermia and then as the star becomes a red giant, become increasingly habitable and evolve complex life. This would especially be the case on something like an ice shell world (i.e. Europa) right at the frost line which becomes a water planet as the ice melts. Ice shell worlds could have lots of life on them and would . Unfortunately, prospects for sentient life, or at least sentient spacefaring life, is pretty bleak on ocean worlds and ice worlds.

There is also the (compelling) argument that humans are among the first species in the universe since in addition to the low-metallicity of earlier stars, lower energy stars like K and M dwarfs have a lower energy input into planets around them meaning a slower rate of mutation and thus slower speed of evolution. So there may not have been enough time in planets around those stars to evolve complex life.

 

[GeographyDude]

It’s time to take UFOs seriously. Seriously.

Back in late April, the U.S. Navy released tapes of three cases.

Unidentified simply means unidentified.

——————

Most discussions of the Fermi Paradox dismiss UFO’s at the beginning.

I’d rather not do that.

I wouldn’t mind having a sprinkling of, say, the half dozen better cases.

 

[GeographyDude]

From my understanding, if you changed the ratio of a few elements like iron and oxygen during Earth's formation you should have a faster Great Oxygenation Event by a few hundred million years (less iron for the oxygen to bond to) and thus have more opportunities for a Cambrian Explosion earlier on (aerobic respiration might be a prerequisite for complex life) leading to more opportunities for sentience. Species diversity remained low until 600 million years ago, which means Earth wasted perhaps 3.5 billion years after life first appeared to evolve down the path toward sentience.

I’m want to first ask the earlier question: How long after we got a (?) threshold of enough oxygen, was the transition from prokaryotic cells to eukaryotic cells?

 

[GeographyDude]

full interview, March 2nd 1978

Back when there wasn’t that many evening talk shows at all, and the Tonight Show with Johnny Carson was a pretty big deal.

And Carl Sagan was a semi-regular guest.

 

[NHBL]

A few random thoughts:
In assuming that civilization will be detectable, we're assuming, primarily, that they use radio/radar over a significant percentage of their time as a civilization, at significant power levels. Here on Earth, less communication is done via broadcast, with fiber optic cables, cellular (which means low power) networks, and the like. We could probably dump broadcast TV and Radio if we wanted to. Radar--would we need anything really powerful if we were not a warlike species? In the absence of war, GPS plus wireless networks would do just fine at collision avoidance. Good bye Radar. And over time, good bye detectablilty of Earth's civilization.

Suppose VISION is rare? Would a race that can't detect the electromagnetic spectrum biologically reach for the stars? Sure, it has effects such as heating things up, but would they ever be able to DETECT the stars as stars? If they did, would they ever develop the desire to GO there.

 

[GeographyDude]

It's weird that everyone just accepts that the drive to colonise the galaxy is a given. We aren't exactly jumping at the chance to send people to live on other planets. We only went to the moon to make a point to our enemies, and we are not in a hurry to go back. A majority of people disagreed with the moon mission at the time, and a majority isn't interested in spending money on Mars.

The X million years estimate assumes our eventual colonies are actively participating in establishing as many colonies as possible, but if there is no technological solution to make this easier or worthwhile, no anti-gravity, no ftl, no unobtanium, etc, then there is a good possibility the human race isn't going to colonise the entire galaxy. In fact it will most likely take an unbelievable amount of time to just spread throughout the solar system. Not because we can't, but because we can't be bothered.

Where are all the aliens? They are at home watching alienflix. Travelling to Earth is exhausting.

The standard answer is that if only a small percent are colonizers, then “inevitably” even this small percentage will colonize the Galaxy. I don’t like this standard answer because it rather assumes that N number of tech societies is large.

If instead . . .

We only have, say, 50 technological civilizations in the entire Milky Way Galaxy, then what percent are colonizers really matters. If 90% are not, that leaves 10% or just five measly civilizations who might potentially dance across the Galaxy. But of course each of these five could be derailed for all kinds of individual and quirky reasons.

 

[Arkenfolm]

I’m want to first ask the earlier question: How long after we got a (?) threshold of enough oxygen, was the transition from prokaryotic cells to eukaryotic cells?

It isn't know for certain, since there's some indication eukaryotes evolved earlier than the Great Oxygenation Event 2.4 billion years ago but didn't become widespread until a few hundred million years afterward, or they may not have evolved until around that time.

I think the diversity of archaea suggest there's plenty of possibility for evolution to experiment even without oxygen though. In general I think there's a hell of a lot of discoveries to be made regarding archaea which would be relevant to Precambrian life in general. That and other early eukaryote fossils.

Suppose VISION is rare? Would a race that can't detect the electromagnetic spectrum biologically reach for the stars? Sure, it has effects such as heating things up, but would they ever be able to DETECT the stars as stars? If they did, would they ever develop the desire to GO there.

They'd detect it eventually assuming they develop industrial technology. We didn't know anything about the EM spectrum either for the longest of time, and even less about other highly important concepts like radioactivity.

 

[NHBL]

They'd detect it eventually assuming they develop industrial technology. We didn't know anything about the EM spectrum either for the longest of time, and even less about other highly important concepts like radioactivity

We didn't know about the EM spectrum, but we had pretty good natural detectors for part of i, which led to discovering that visible light was a part of a much larger spectrum. Would a species that didn't have eyes have any incentive to detect the rest of he spectrum?