I don’t suppose that Frank Drake intended his famous Drake Equation to be anything more than a pedagogical device, or rather, an illustrative tool to explain what he viewed as the most significant things we would need to know to figure out how many other civilizations might be out there in the galaxy. This was back in 1961, and naturally the equation was all about probabilities, because we didn’t have hard information on most of the factors in the equation. Drake was already searching for radio signals at Green Bank, in the process inventing SETI as practiced through radio telescopes.
The factors here should look familiar to most Centauri Dreams readers, but let’s run through them, because among the old hands here we also get an encouraging number of students and people new to the field. N is the number of civilizations with communications potential in the galaxy, with R* the rate of star formation, fp the fraction of stars with planets, ne the number of planets that can support life per system, fl the fraction of planets that actually develop life, fi the fraction that develop intelligent life, fc the fraction that go on to communicate and L the life time of a technological civilization.
The idea of course is that you can multiply all these things together to derive some idea of how many civilizations are out there whose signals might be detected on Earth. Multiplying all those factors obviously ratchets up the uncertainties, but given that we have been proceeding with our investigations, and fruitfully so, for decades since Drake addressed the 1961 meeting at Green Bank, it’s interesting to see just where we stand today. Bringing us up to date is what Pascal Lee did at the recent symposium of the Interstellar Research Group in Montreal, where he gave the talk you can access here.
Image: M31, the Andromeda galaxy. Are civilizations common in spirals like this one? The Drake Equation is one way of probing the question, with ever-changing results. Credit: Space Telescope Science Institute.
Lee (SETI Institute, NASA Ames) is all too aware that with Earth as our only datapoint, we run the risk of being eaten alive by our own assumptions. So he takes a conservative approach on each of the factors involved in the Drake Equation. I think some of the most interesting factors here relate to the nature of intelligence, which didn’t pop up until halfway through the life of our star. That’s assuming you posit, as Lee does, that the appearance of homo erectus signifies this development, and this datapoint indicates that intelligence is not necessarily a common thing.
After all, the creatures that ran the show here on Earth for well over 200 million years do not seem to have developed intelligence, if we take Lee’s definition and say that this trait involves making technologies that did not exist earlier. A beaver dam is not a mark of intelligence because over the course of time it remains the same basic structure. Whereas true intelligence produces evolving and improving technologies. Thus primitive humans learn how to control fire. Then they make it portable. They start using tools. That this occurs so late causes Lee to give the fi factor a value of 0.0002, derived by dividing the median duration homo erectus has been around, roughly one million years, by the age of our planet. That’s but a sliver in Earth’s geology. We can reasonably argue that intelligence is circumstantial and fortuitous.
And what about intelligence developing into a technological civilization? This one is likewise interesting, and I like Lee’s idea of pegging 1865 as the time when humans became capable of electromagnetic communications because of James Clerk Maxwell’s equations. Thus we go from intelligence to communicative technologies and SETI possibilities in roughly a million years, from homo erectus to Maxwell.
But that’s just Earth’s datapoint. What about ocean worlds, or life forms in gas giant atmospheres or in heavy gravity surface environments where attaining orbit is itself problematic and perhaps the stars are rarely visible? Intelligence may develop without producing advanced civilizations that can become SETI targets. Here we have to get arbitrary, but Lee’s choice for the fraction of intelligent life turning into communicating civilizations is 0.1. It happens, in other words, just one time in ten. He’s being deliberately conservative about this, and the result has a lot of play in the equation.
Take a look at the rest of Lee’s values, based on all the work on these matters since the Drake Equation was conceived. Here’s his summary slide of the current outlook. I won’t run through each of the factors because we’re making progress on refining our numbers for those on the left side of the equation, whereas for these last two points we’re still extrapolating from a serious shortage of data. And that is certainly true in the last factor, which is L.
Obviously how we evaluate the longevity of a civilization determines the outcome, for if it is common for advanced technological cultures to destroy themselves, then we could be looking at a galaxy full of ruins rather than one with a flourishing network of intelligence. Our own threats are obvious enough: nuclear war, pandemics, runaway AI or nanotech, the ‘democratizing’ of potentially lethal technologies and more. Speculation on this matter runs the gamut, from a lifetime of 100 years to over a million, but historically human cultures last somewhere between 500 and 5000 years.
Is the anthropocene to be little more than a thin layer of rust in the geological strata? Lee sees 10,000 years for the lifetime of a civilization as a generous estimate, given that we are global and have more than the capability of self-annihilation. If this estimate is correct, we arrive at the conclusion shown in the slide above: The number of civilizations in our galaxy most likely equals one. And that would be us.
I was once asked in the question session after a talk how many civilizations I thought were in the Milky Way right now. I remember hedging my bets by referring to everybody else’s estimates – the 1961 estimate from the Green Bank meeting had ranged from 1,000 to 100,000,000, whereas one recent paper pegged the number at 30. But my interlocutor pressed me: What was my estimate? My conservative nature came to the fore, and I heard myself answering: “Between 1 and 10.” That’s still my estimate, but as I told my audience then, it’s the hunch of a writer, not the conclusion of a scientist, so take it for what it is.
Now I find Lee reaching the same conclusion, but two things about this stick out. If a single civilization did somehow get past what Robin Hanson calls ‘the great filter’ to emerge as a star-faring species living on many worlds, then their presence could still make all our talk of an Encyclopedia Galactica relevant. We might one day find that there is indeed a thriving network of intelligence, but one based around the work of a single Ur-civilization whose works we have better learn about and emulate. It’s a pleasing thought that such a civilization might be biological as well as machine-based, but all bets are off.
The other point, and this is one Lee makes in his talk: If life is common but technological civilizations are rare, that still leaves room for a value for N that takes in not just the Milky Way but the entire universe. N=1 means that the visible universe should contain 1011 civilizations, a satisfyingly large number and one that keeps our SETI hopes alive. We had better, in this case, concentrate our attention on nearby galaxies to have the greatest chance of success. There are 60 of them within 2 million light years, and over a thousand within 33 million light years. M31, the Andromeda galaxy, may deserve more SETI attention than it has been getting.
You guys (or someone) should create a “Drakepedia” consisting of a page for each term of the Drake Equation with a summary of the latest relevant research and an estimated value, or an interval and best-guess within it. Of course, the home page would show N’s latest value and link to research on SETI generally. I’m sure you get the gist. I suppose the SETI organization would be the obvious one to do this but perhaps they have political reasons not to.
The problem is that we really, really do not know what the probabilities of the life, intelligence, and transmitting time terms are. These are the great unknowns. We hope that exoplanet biosignatures will at least constrain the probability of a habitable planet with life term. But intelligence? How long a civilization will transmit? These are nothing more than speculation and our own biases.
To reiterate a point I made in another comment, the DE assumes “contemporaneous” transmissions and then only from the homeworld – i.e. no star-faring at all, let alone transmissions continuing long after a civ end.
At one time a large part of how I saw myself and the universe came from Carl Sagan, but, I never could believe his working of the Drake equation. He plugged in a whole bunch of ones and then balanced it by making L 50 yrs. I think even most of the estimates of L are far too low. Part of this is because of how we define culture as individual cultures (ancient Egyptian etc.) but We’re talking about a species culture and ours has advanced in an uneven but accelerating fashion since our beginnings.(and even before?)
For almost the entire period of hominid emergence, nothing much happened, other than the slow grind of evolution slowly increasing our brain size and physical form, especially compared to our great ape cousins. The first big change was sometime in the middle Paleolithic when new forms of flints appeared, followed in the upper Paleolithic with increasing cultural artifacts. The first cities appeared towards the end of the last ice age. Writing some 5000 years ago. Roman civilization was perhaps the peak, until it was finally superseded a few centuries ago. But it was the industrial revolution that really jolted our current civilization forward, both in terms of population size and technological capabilities.
I would argue that our science-based technological civilization is quite young, and we know radio transmissions were only started in 1900, 1.23 centuries ago.
So what should L be? Strictly speaking we have only been a transmitting species for just over a 100 years. Most cultures do not survive for long, a handful of millennia at best, and we really have no idea whether technology lengthens or shortens that period. We can hope that once technology arrives, subsequent cultures will continue with their use and development, but as we know from Rome, we lost some of their technological knowledge, and so there is no guarantee that it will continue. We have a vast technology knowledge base and repertoire, but its storage is fragile and getting more ephemeral. We also know from our experience of trying to create knowledge systems that capturing knowledge is hard, so without direct experience from practitioners, it can be lost. A new “dark age” might be very hard to recover from.
What is your thought on L?
This is a really important point because we seem to think of the galaxy as a cozy backyard and fail to raise our sights beyond its edge. Even relatively few scifi authors look beyond the galaxy. Have any scifi movies?
But still, the consequences tend to stymie us, and our imaginations fail. If L is around 10,000 years, then most of the other civilizations in the galaxy if 1<N<10 civilizations will not bother to transmit as 2-way communication is hopeless. They may transmit their knowledge in the hope it is of some value to others. But if so, there is no indication of that yet.
Clearly, this logic applies in spades to civilizations in other galaxies. Why would a civilization transmit to other galaxies given the even greater distances and times?
But it is here that imagination seems to fail.
If there are indeed many billions of civilizations in the universe, all technological, there must also be a vast variety of outcomes. Even assuming c is an absolute, unbreakable speed limit, any entity can cross any distance in space in a perceptual instant traveling at c. That implies the technology of transmitting with sufficient bandwidth to transfer at a minimum a physical body and mind is available. [Surely that must be the case somewhere]. Therefore, once the receiving station has made its slow journey between the galaxies, entities can travel across the universe. It may mean the entities are forever separated from the civilization (biological or machine) they started from, but that just means that they could start a colony of their home civ in a new galaxy, effectively extending the L of a civilization. There is no need to assume that the civilization that sets up the dispersion of receiving stations is the civilization that uses them once operational. A civ in the Andromeda galaxy sending receiving stations to our galaxy at 0.1c would know they are in place and functioning in less that 30 my. This is longer than a single civilization's lifetime, but not for successive ones that might restart even 10 my or so. Once in place, the civilization of whatever substrate it is based on can be star-faring, at least between transmitting and receiving stations. [c.f the transport in the movie "Contact" where the aliens Ellie meets are not the builders of the system.]
Therefore we open up the issue of N in any given galaxy. TMy example is just an extrapolation of previous analyses of star-faring civilizations in our galaxy populating the stars, or from the Von Neuman replicators even earlier. I just extend this to the universe of galaxies to try to increase even the most conservative number of civilizations that have ever arisen, adding a means for minds to travel without biological or mechanical body deterioration (again, not new), and arriving at the answer that the universe, even our own galaxy, should indeed be filled with intelligent life. It may not travel in clunky, physical starships, but rather at light speed between destinations.
What are the implications for SETI? If this was indeed the case, then the bandwidth would have to be far higher than the radio and optical wavelengths we currently use for SETI. It will likely be in the most extremely short wavelengths, sent at high power, with enough redundancy and error correction to ensure fidelity at reception. The transmissions will be very focused and therefore unlikely to be detected by leakage. After that, how the network is managed is purely speculative and for the communication engineers to work through.
And maybe, just maybe, there is a transmission station in our own system, possibly even on Earth (although better on the Moon or even further out, like Iapetus), just waiting to be activated by a civilization ready to meet others…
I believe quite a few sci-fi movies and tv shows have talked about locations in other galaxies. In fact, the first Star Wars movie started with “In a galaxy far, far away …”. I suspect most of them use it as Star Wars did, to remove the story from our galaxy in order to halt any questions about where Earth fit into it. But you’re right, most of them take place in the Milky Way. I’m guessing that it’s so they can refer to stars and even planets by name in order to spark viewers’ imaginations about possibly going there and looking up in the sky to see where such and such happened.
IMO, the term “galaxy” in this context means another star system. I see it over and over again in scifi movies. If a spaceship leaves Earth for another galaxy, then there should be a period when the stars stop rushing by while in intergalactic space, and then start again in the destination galaxy. That doesn’t happen, so they are still in the same galaxy.
Having said that, it was used correctly in the new Ahsoka spinoff, as the ships did indeed seem to travel to another galaxy, and so I can accept that Lucas could indeed have meant in another galaxy. But terrestrial-exact humans (but maybe with midichlorians?) evolving elsewhere? Fantasy.
I just think science-illiterate movie producers/writers/directors just like the word “galaxy” better than “the wordier “star system [X]” or just plain “[X]” when meaning another known star system or planet in that system.
[X] = name of the system, i.e. Proxima, or a planet in a system, eg. Trantor”.
I think James Blish did have his spindizzy-powered cities travel across intergalactic space towards the end of his “cities in flight” stories.
Galaxies as distinct separate star clusters not part of our galaxy were only determined around 1920. Prior to that, authors could not conceive of travel to another galaxy, just to places within our galaxy including star clusters, some of which were galaxies like the Andromeda galaxy, M31.
The Milky Way is about 13.6 Billion years old; our solar system is something around 4.6 B years old. The formation of life, intelligence, technology and communications all occur within the decimal point for our solar system, i.e. a few million years. we need a few more decimal places to express how briefly our own technological culture is expected to persist, say something like 4,600,010,000 (basically in the noise of current estimates) where the last 10,000 years is the estimate for our persistence. In our galaxy then, we could develop a factor attempting to assess the number of existing contemporary communicating cultures. Uh, it gets really small.
As we explore communications technologies that involve manipulating gravity, light, entangled particles, etc. even if there were a contemporaneously existing civilization, how do we know how to even listen for them?
Finally, if there were any out there, why haven’t they “found” us?
Questions about whether there are other intelligent life forms informs our philosophies, and should inform development of our civilization. By out own values, if we are alone in exhibiting intelligence (of the kind we value) we can’t allow that uniqueness to be squandered on the kinds of behaviors our species exhibits toward each other and towards our co-inhabitants of this planet.
As impressed as I am with human potential, I’m not hopeful about our species surviving too long, to say the least, nor becoming a long lasting civilization among the stars. It’s hard to be hopeful about there being another, better one “out there”.
There is certainly evidence that we are improving as a species/cultue. But why assume our culture or even species, should be the ones to spread to the stars? What about a future human species? Olaf Stapledon envisioned 18 human species, the last living on Neptune, until the sun went supernova and wiped them out. With genetic engineering, we will likely be able to create new human species in far less time than Stapledon envisaged. Intelligence, perhaps superintelligence, might best be embodied differently, with more hope of spreading to the stars in a beneficial, rather than predatory way.
IOW, I don’t think we should look back at our evolutions and history and despair. But I admit, I am a techno-optimist.
I read Stapledon as a child. I doubt that I fully comprehended the philosophical predicates represented in his writing. But jolly good writing. In terms of your view that there is evidence “we” are improving as a species/culture, I worry that specie improvement (i.e. evolution) is blocked when so much technology is used to avoid the impacts of a life exposed to competitive pressures. In terms of culture, I worry that relatively new developments in social media have turned up the volume on humanity’s worst while drowning out humanity’s more worthy (ethically, morally) sentiments. Offhandedly assuming you are aware of work showing that animus toward other is genetically based and that those so “provisioned” are about 30% of humanity, I worry that trends in social media and the resultant organizational impulses that are drawn from that may give the more “hateful” elements of humanity, even though a minority, some advantage over the majority of people who are more inclusive and open minded. In my point above I raised the question of sustaining a multi-generational project organization when humanity has not yet demonstrated the ability to sustain long-standing political and cultural organizations. I would hate to be in a starship only to learn that the home world had reduced itself to a pre-technical state of existence!
There are many explanations for the Fermi Question. If you haven’t done so, you can start here:
Fermi Paradox and
A list of solutions to the Fermi Paradox
Alex, based on you taking the professor stance, I took the student stance and reviewed what I knew, or thought I knew, about the controversy you labeled the Fermi Question. But yes, I know something about this and have actually developed my own contribution. I’d warn it may be derivative in a way, by getting specific when so many ideas are very broadly cast. My main arguments are against any visitation by advanced civilizations. I base this on 3 primary causes:
1. No magic. In other words, no FTL strategies available within physics.
2. Radiation. Given an assumption that any visitation would be by physical beings, and that said life forms would have developed on a planet somewhere, and sustaining the assumption of no magic, interstellar travel entails exposure to radiation that it is hard to conceive that any planetary species would tolerate. The idea of shielding, bound into the no magic assumption, means any vessel must transport the mass of the shielding along with the life support components, thrust components, and on and on. Radiation itself predicts the need for very massive transports, and very massive transports run up against other constraints, especially transit times.
3. Specie Life Cycle. The transit times even for “short” journeys are long. Even a long lived species, say smart turtles or such, would rarely have evolved lifetimes sufficient for an individual to survive even a one-way trip interstellar. Notwithstanding hive-mind species, the general case would be that any journey is multi-generational, with all the complexity that entails adding to the payload requirements. Given there is no magic assumed, what kind of propulsion can we imagine that would be able to accelerate larges masses to a fraction of the speed of light? Humans don’t know that answer today. My decision that we have not been visited is not based on thinking anything is impossible; rather the probabilities multiplied out “Drake Equation” style show it less and less probable that anyone anywhere has overcome the sheer physics of interstellar travel.
On the other questions, like why haven’t we seen or heard any civilizations squeaking about, I accept that ground is well covered as you pointed out.
Drake’s Equation would seem to target intact, functioning “civilizations”. That’s what we would want.
But how about the ruins/remains (on the macro scale) of former civilizations, or cadavers, fossils, artifacts, et cetera on smaller scales? How many potsherds and other artifacts do civilizations leave behind; how durable are those artifacts, how widely are they strewn away from their origins, and how likely are they to be found — and recognized?
And on the matter of recognition, how likely are two spatially and temporally adjacent civilizations to fail to recognize each other? And for what reasons? Could one have abandoned biology and miniaturized itself to approach the Planck dimensions? Or have originated in dimensions akin to dark energy and dark matter?
If such be the case we may be unknowingly “rubbing elbows” with them while they are smirking (or their equivalent of it) at us.
The Drake equation is explicit about N being contemporary (or at least within our light cone) and transmitting while the civ is extant. This “bias” may be because we are a social species that loves to chatter and wants 2-way communication. If we were descended from cats, we might not have that desire. Our transmitters might be more like territory markings to tell others to stay away.
But once we emerged from our purely hunter-gatherer tribes and created civilization (i.e. cities) these organized polities survived for relatively short periods, collapsing for a variety of reasons. But each left some remnants of itself in structures, artifacts, and writings, that were subsequently discovered by later civilizations. Our own has looked back to Ancient Rome as a previous civilizational height, or “golden age”. [Is classical architecture so beautiful that it has been copied so frequently in the modern age, or more of a reverence for this earlier period?]
While our prior civilizations would not leave much trace after 10 my, there is no reason to assume that would be teh case with more advanced technology, especially based in more benign environments. Could technology, even transmitters operate long after the constructing civilization had vanished? Could such technology be operating, as the Krell technology does in “Forbidden Planet”, waiting to be used? On this site, we have had posts about creating archives for future civilizations to reboot themselves with our knowledge. Why not advertise its presence with some sort of beacon, especially if it can only be reached with sufficiently advanced technology? For that reason, SETI in its current form is worth doing, even if the prospects for success appear poor. We just might stumble on a discovery.
I’m reminded of a short story by Stephen Baxter about the universe’s increasing expansion as it starts to rip everything apart. The sky lights up with civilizations transmitting their presence as they face oblivion. So far we do not see any such signs, but perhaps this is because the “galactic club” is more like our internet rather than radio stations. We have to reach an “ISP” and get access. Maybe that also requires passing some “joining application” before we can connect.
The bottom line is that a universe full of civilizations, past and present, does suggest the Fermi Question is still relevant.
A low number of civilizations would explain the Fermi Paradox (no contact). But even a few civilizations per galaxy still means there are billions of civilizations across the breadth of our universe. If there is a purpose to this existence thing, it is life.
Hello Paul,
I open the comments by reminding you that the Drake equation was recalculated a few years ago on the basis of our new cosmological knowledge acquired since the 1960s: the statistical demonstration concluded that the number was much greater than 1 within a radius of 17,000 light years It can be read here : https://arxiv.org/abs/2004.03968
If I’m not mistaken, here’s the prospecting radius ;) https://ibb.co/CscdyGm
Fred – France
Fred, the Drake Equation has been recalculated in a number of ways over the years. In fact, searching the Internet for it often reveals varying forms of the basic equation, and a variety of solutions. What Lee is presenting is one of the most recent, but you’re right, it’s certainly not the only one.
“…concentrate our attention on nearby galaxies to have the greatest chance of success. There are 60 of them within 2 million light years…”
I turned to the back of an envelope and started scribbling. If there’s just 1 other radio-capable civilization in our galaxy, METI requires an isotropic antenna for full sphere coverage (positioned in space so the ground isn’t in the way). The furthest we have to reach everywhere within the Milky Way is 70,000 ly. That’s our baseline.
2 million ly is 30 times further, or an incremental path loss of about 30 db. However, the Andromeda galaxy covers only about 2 square degrees out of over 40,000 for full spherical coverage per the above paragraph. Our antenna gain to solely targets that galaxy would be about 43 db. That’s routinely done over a large swath of the radio spectrum.
The additional path loss from 70,000 ly to 2 million ly is about -30 db. For equal transmitter power, we therefore have a 13 db (20 times) surplus targeting Andromeda vs the Milky Way. That is, we can transmit to every possible radio-capable civilization there more effectively than within our own galaxy.
Of course, we can’t. We need orders of magnitude more transmitter power than what is currently possible to perform either of those experiments. It’s just less impossible. The longer reply latency might also be a problem (heh).
Keep me in a transporter pattern buffer and restore me when we get a reply. ;-)
From your numbers, I gather we do not need to be a full K2 civ to achieve the power output for transmission to the nearby galaxies. How many GW do we need, and is that inside or outside the bounds suggested for Lubin’s DE-STAR 4 laser arrays? How much of our current planetary electrical energy generation would be needed to create the transmission pulse?
I must say that I find Lee’s approach to estimating “fi” a little too simplistic. For a vast majority of the Earth’s history life simply wasn’t complex enough for the parameter space it could explore to even contain the possibility of intelligence. We don’t even see the appearance of evidence for a nervous system until 550-600 million years ago. I think a more reasonable approach is to take that appearance as the first moment that intelligence could even be stumbled upon by life as a possibility; otherwise you’re just rolling a 6 sided die and becoming confused as to why you never get a 7.
It really depends on what you mean by intelligence. If it is just reacting to the environment in a non-random way, then bacteria have some level of intelligence. Plants have no nervous system, let alone a brain, but seem to have some quite sophisticated behaviors, albeit on a very different timescale to animals.
But if intelligence is about human-level capabilities, then this is quite evolved and even emergent, with technology multiplying those capabilities. It is possible technology will supersede human intelligence too, just as we supersede all other animal intelligence.
What is that #7 on the die turns out to require machine superintelligence, because our attempts are no more effective than mudskippers flopping about in the mud above the water compared to true land animals?
Agreed. And very important. It appears the bottleneck that took 3 billion years was organisms with differentiated tissues. Once that happens, you “only” need half a billion years to technology. And one could guess that most of those years were spent in a technology-proof space, too (harder to tell, as we don’t know what the impossibilities are. Do you need to be land-based? Do you need long adolescences for children? Do you need language? Do you need bipedalism? Thumbs? Social hierarchy?)
Important, because any of the factors in the DE could/should be subdivided using the bottlenecks in our history as hints that these are the low-probability events whose values actually drive the equation and require refinement.
I get that the author of the talk is being provocative with his figures. This is essential in order to promote the kind of erudite and reflective comments seen here. But if I myself wanted to suggest that we are, in fact ‘alone’ in our galaxy, a little tinkering with the figures could quite easily validate that premise. Starting with the known knowns, entering the desired outcome and twiddling the figures in between is just basic maths. Of course, I too am being a little provocative here.
This estimation is based on 1 civilisation for the duration of it’s existence (If i properly understood)
With the knowledge of Civilisations being so rare, you would assume they would either not care, or throw all caution out of the window and broadcast it’s existence With the knowledge they acquired so there might eventually be an outlier civ who makes it. And this message might persist after it perishes as a historical record. In other words, if it’s about one civilisation at a time for the milkyway, we should still assume finding records/broadcast of civilisations long gone.
Next to that, even if our civilisation is doomed, we are also inching closer to seed our local universe with Von Neumann probes or life itself.
I also don’t share the negativity of human civilisation being doomed as a whole, sure dark times seem to lie ahead, but we only need a civilisation of a few million to persist, however macabre, a great dying like a modern version of the plague might be required to reset humankind on a sustainable path.
It’s all about intelligence, and it’s likely evolution. Not to be confused with civilization. They can digress after a point in time.
SETI is the search for intelligence. We continue to fail to find a contemporaneous biological civilization as the basis for that intelligence, possibly because we persist in equating intelligence with continuous existence of said civilization.
Consider:
L = to time from Von Neumann’s observations on computer architecture to successful transition to machine intelligence.
The great filter is the successful transition to a post biological machine intelligence. Hurdles include tech-based self destruction and hostile AI.
Our insistence on basing machine intelligence on our biological neural circuitry is flawed.
Biological brains did not evolve, and do not continue to evolve to maximize intelligence, immortality, civilization, or space travel. DNA based mutation/evolution does not work to that end.
An immortal super intelligent machine is more likely than a immortal super intelligent brain. (A super intelligent biological brain might be impossible to engineer).
N (contemporaneous biological civilizations) is a persistent low number because all biological intelligences either wallow/die out, or transition to machine intelligence as a logical extention of the desire for increased intelligence and immortality. The desire to expand intelligence results in shortening of our definition of ‘life span’ of the civilization. Or they die out as a consequence of successful AI take over.
The above results in the premise that whole immortal “civilizations” of intelligences can be contained in machines, and 8 billion biological brains on earth, working together, couldn’t find them, even if they could accept they existed.
The pursuit of intelligence and immortality can be compared to an addiction. If it works, great. If it doesn’t, too bad. In either event SETI comes up blank.
Hi Dimjo, Yes, i overlooked the tranistion to technological civilisation, or hybrid versions (So many factors to keep in mind): in that light needs for expansion might fade away since mechanical needs are different from those of biological ones. Maintenance vs Reproduction. Either way, there is just as much reason to be positive about our own persistence in one form or another as there are reasons to be pessimistic.
Not sure biology will fizlle out, it’s more likely that biology becomes technology that can be maintained itself. But even then the need for reproduction can become obsolete. I doubt that makes the quest for knowledge obsolete though, learning and communication go hand in hand.
In general, the fact we haven’t found any civilisation does not tell us much, except that they aren’t close by, and there isn’t a galactic empire, all other solutions are still open. The discussion that aims to formulate a solution remains more scifi then science: it would help to take a more agnostic approach. Afterall, until we actually find another civilisation we will see an article that demands immediate satisfaction every week. This is where we show we are addicted indeed, as you conclude.
(But the rewards of reaching one step higher in understanding are very satisfying: I am entertained)
I have a question; wouldn’t the development of AI and the subsequent dying off of the original intelligence argue for long-lasting civilizations, long-lasting sources for our detection? I continue to favor multi-generational, robot-based missions to stars, assuming they can take the higher accelerations needed to get to a fraction of light speed, they can be designed to need less radiation shielding than a life form, and they are getting to a level of sophistication that argues well for their independent operation at the destination. I don’t worry about the machines getting to the destination and sending back data. I worry that humanity won’t survive the trip even here on the home planet!
More people should read The demogra-fate hypothesis by Thanh Nguyin-ba. When societies get rich, more people enjoy all the good things which money can buy. Many lose interest in the hard work of raising children. The birthrate has fallen below replacement in many countries with different political systems, races and religions. Consumerism is a common factor. A shrinking population does not need space colonies. This is another limit to L that needs to be pondered.
This equation is an example of our ineptitude to see beyond our selves. Why is this? Because we live on a planet with a extremely odd fact that has nothing to do with life or civilization or our ability to communicate across the immense distances of space. “There Are No Coincidences”
This statement is a paradox.
https://www.psychologytoday.com/us/blog/connecting-coincidence/201607/there-are-no-coincidences
We are here and understand the significance of total solar eclipses.
How common this occurs in earth like planets gives an alternative to consider in the possibility of other civilizations existing.
I sense an Anthropic principle. Not an explanation but an alternative to consider.
https://en.wikipedia.org/wiki/Anthropic_principle
Most of the “existential threats” aren’t anything of the kind. Even nuclear war would leave whole continents untouched. (Would the US, Russia, or China really want to lob missiles at Brazil?) It’s very hard for me to imagine any technology-spawned danger which could actually end human life on Earth, since there’s a negative-feedback effect: at some point the population declines to the point where it can no longer support the deadly technology. Recovery might take decades or centuries, but that’s an instant on evolutionary or cosmic scales. And a technology which is self-sustaining (killer robots, say) is simply a civilization itself, so no help for the Drake numbers there.
The two “answers” for the FP I keep coming back to are:
1. Lack of data — we still haven’t done a long-term, sky-wide, broad-spectrum search for signals. Until we do that, we’re taking bucketfuls of water from the ocean and speculating about the existence of whales.
2. Interpretation — the presence of large technological civilizations might be mis-identified as natural processes. _All_ “anomalies” or unsolved puzzles in cosmology or galaxy evolution should be analyzed in terms of whether life plays a role. Why do They like arranging stars in spirals?
If any Centauri Dreams readers are unfamiliar with Jim’s work, now is the time to start with The Darkling Sea. Superb writer.
Thanks for the recommendation. I just ordered a copy.
“a darkling sea” by cambias
The idea that existential threats aren’t really existential to humans is worth thinking about. Are any of the current threats really existential? If by that we mean that we are reduced to a few million humans (or much less) at possibly a stone age level of technology, scattered over the globe then possibly only extreme threats or combinations of threats will kill us all. For example if we make the Earth’s surface so hostile to life through a combination of climate change (temperature extremes, storms, droughts, fires etc. etc.), pollution (poisoning of the oceans and fresh water with industrial and agricultural runoff, and plastics, including microplastic waste), warfare of all kinds including a nuclear exchange at some point, and occasional pandemics, would this effectively eradicate us or make it unlikely we will ever recover? Hard to say but we’re doing a pretty good job of doing the experiment aren’t we?
Yes, a smaller population wouldn’t necessarily mean our dimise. Only when we make earth truely into Venus we would be doomed, as long as that doesn’t happen there could be various scenario’s upon which we can survive in hideouts/pockets more suitable.
(and why does everyone assume we would fall back to the stone age? renewable energy make us more independent of the bigger networks and less prone to fail: the worldwide internet may be gone at some point (unlikely )but we would still have our local networks and harddrives) (Bit similar as to how North Korean’s pass on (western) infomation through USB Sticks)
Good morning,
Finally, I find that P. Lee’s conclusion in his Drake equation is the most interesting: he clearly distinguishes between the [strong?] probability that life can develop elsewhere in the universe from chemical compounds but it seems much rarer that a technologically advanced civilization can develop, especially at almost the same time as ours. If we assume that we are the first, shouldn’t we think about how to “leave a trace” – a technosignature – for future civilizations that will be born after us and if so, which one? ;)
Fred
It’s hard to disprove the idea of remnant populations surviving in various places on the Earth I agree. Whether these pockets could allow for a full recovery to a worldwide technological civilization is debatable. You’re right Ivar in that the collapse to a stone age civilization is over-used. The type of scenario you suggest is frightening enough, even if a few of us are still huddled over our computers, talking to a few other people and using generators powered by renewables a few hours a day. It doesn’t sound like the type of civilization I want to be part of. Let’s get to work removing people from office who promise change but then continue with more of the same policies such as expanding fossil fuel networks such as the Trans Canada Pipeline expansion (taken over and built at a cost of over 30 billion dollars and rising by our federal government and shown by the Parliamentary Budget Office to be a non-starter as far as profit is concerned). I can think of a leader in Canada who does exactly that. Good at smiling and glad-handing but terrible at making the tough decisions.