I love the theory of Great Filters. I'm pretty sure that #9 on the list should be "social media", though. Or in general, "self destructing human behavior."
I have absolutely no education on the subject and have done almost zero research, but I wonder if this "Self Destructive Behavior of Humans" is merely the evolutionary local optimum of tribal behavior.
Historically, it has been an advantage to have a strongly tribal drive. Cohesive groups achieved much more than individuals and yet were small enough that they could effectively self-police and agree on common goals.
However, as the capabilities of each tribe increased and the world became smaller through travel (and now the internet), tribalism, us-versus-them still remain part of our basic instincts and subconscious, however it is now the source of international and high powered conflicts.
10000 years ago, our tribal programming resulted in the survival of a group of families and the development of townships and emergence of societies. If a tribe got particularly bloodthirsty, their impact was almost purely local and perhaps eventually their notoriety resulted in a decline.
Now, sticks and stones have been replaced by nuclear weapons and ICBMs. A first strike capability is no longer dangerous to just one village, but entire continents.
Perhaps our technological evolution has outpaced our biological and social evolution, and the behavior that was optimal even 1000 years ago is now a grave danger?
Any intelligent organism will have to overcome the biological local optima that brought it to the intelligent state before further developing as a species.
We already have explored a variety options, each with their own advantages and downsides:
1. Free individuals in a distributed system in a cottage industry economy.
2. Semi-free individuals who gather in tribes formed around value-generation (i.e. corporations).
3. Centralized system with individuals who are assigned functions.
Future progress will have to be technological and will change what it means to operate in the afore-mentioned scenarios 1,2,3.
This resonates with me. I've long said that if we are to launch any kind of significant space-faring civilization, we will need to some extent to become a different species, through cybernetics & drugs or genetic engineering (probably a mix).
Our current biggest challenge is to make ourselves 'smarter' (i.e. less susceptible to the biases baked into our DNA). Otherwise, it's likely only a matter of time before we cripple ourselves into an extended Dark Age or worse. Constant setbacks resulting from too many of us having ignorant, emotional reactions to incomplete stories with insufficient facts means we're all dancing on shifting sand. It's not a good foundation upon which to build a durable interstellar civilization.
When I was a kid ignorant people kept their thoughts in their heads safe and tucked away or maybe told a few people near them that knew better. Now they let them out on social media where they can find other ill-informed people and reinforce one another. I don’t know a way around this filter step. Maybe it naturally will resolve. As Stewart Brand said, information wants to be free. I will be optimistic enough to believe that means correct information. The science and empathy just isn’t well distributed yet. “The future is already here — it's just not very evenly distributed.” -William Gibson
"Information wants to be free" is a physical law, not a moral rallying cry.
In many cases the promiscuous nature of information works heavily against human welfare. One aspect of that is that incorrect information spreads as well -- sometimes better-- than correct information.
Before you were a kid, people talked and shared secrets and inner desires with one another. What is ignorant, what isn't? Discussion about a king? A president? What sort of people you want to be around? What is dissident can become a movement and become superior.
> Or in general, "self destructing human behavior."
That is definitely a credible theory, and it's currently catalogued as number 2.2 on Wikipedia's list of hypothetical explanations for the Fermi Paradox, where it is given the haunting title: "It is the nature of intelligent life to destroy itself".
From the website: "The Great Silence implies that one or more of these steps are very improbable; there is a "Great Filter""
The paper argues against this in that you don't need a few very improbable.
In fact, there are many parameter choices where none of the probabilities in the Drake equation are particularly low, yet the resulting number of intelligences is still staggeringly small.
tl;dr: All parameters can be a bit lower. Then you don't need any events that are extremely improbable.
But one of the events must be the least likely. And why would it not be significantly less likely than the next least likely event, given that they are uncorrelated?
> However, the result is extremely different if, rather than using point estimates, we take account of our uncertainty in the parameters by treating each parameter as if it were uniformly drawn from the interval [0, 0.2]. Monte Carlo simulation shows that this actually produces an empty galaxy 21.45 % of the time.
Isn't that just elaborated way of saying that some of the parameters of the Drake equation have to be much smaller than we think?
Let's use the simple example you reference from the paper.
If we just use the mean as point estimates, then indeed we obtain an extremely low probability that there's no other intelligences:
Now of course halving every probability is a lot, however now there's no single or few events that have a very low probability of happening. The Great Filter disappears.
The Great Filter thesis is that there has to be one or more very low probability events in the Drake Equation.
However, as per my other comments, you can update the distributions of your parameters in different ways, such that none of the events in the Drake equation have a particularly low probability.
Then the Great Filter disappears and there's no specific or few set of events to point to - it's just that the probability of all events succeeding in combination is extremely low.
Recent data from New horisons mission is interesting, suggesting there are an order of magnitude fewer galaxies (hundreds of billions, rather than 2 trillion) which should be relevant update to Fermi/great filter reasoning.
The probe is near Pluto, and so able to sky 10 times darker than Hubble, but isn't observing the modelled galaxies extrapolated from Hubble observations.
For example, it explains why the sky would be darker from the POV of Pluto than the POV of Earth orbit (Zodiacal dust is relevant at this level).
That said, I’m still surprised that the estimate was ever as high as 2 trillion; I thought the estimate had been the lower 100 billion value for most of my life.
When you realize that even if by some miracle we find a way to travel at really fast speeds we will never explore 99.99999% of the universe is mind boggling.
I find this improbable. Kessler syndrome could well make it impossible to keep a satellite in orbit at certain altitudes. However it is unlikely to create a “shell” that prevents space flight entirely. Kessler in LEO would be cleared fairly quickly (a generation or less) and at higher orbits the debris would be less dense due to the volume of orbital space it covered, which expands at the square of altitude. If we were really determined to get off the planet, I don’t think it would stop us.
I find the space colonization (outside own solar system) a bit too optimistic, while it is 'only' a technical problem, it still might be an impossible problem.
Hm. I tend to think that it's not impossible, but simply very impractical.
Outside of the very nearest neighbouring systems, any interstellar colony would instantly become an isolated new civilisation. There's simply no plausible way for interstellar trade or even just meaningful communication.
All a colony at say, 82 Eridani - a sun-like star about 20 ly from Earth, would have a two-way communication time of 40 years. Even digital "goods" aren't worth exchanging if it takes 20 years to send them and another 20 years to receive any kind of payment.
At a very optimistic 30% lightspeed, ships would take 67 years to get there. This means no one can make the journey within a single human lifetime, unless the lifespan is dramatically increased or some form of hibernation technology is used.
In any case, colonists would be completely removed from Earth and all that effort pretty much requires a suitable target planet to be present. Without radical genetic changes, humans wouldn't be able to thrive and survive on a Super Earth or in poisonous atmospheres. So another factor would be spending tens of thousands of years and unfathomable amounts of energy terraforming planets or changing the human genome beyond recognition.
The same issues would apply to extra-terrestrial intelligences as well, which is why I don't think interstellar colonisation would even be all that desirable in the first place.
First you have to find a suitable host star. Next you need to find a matching planet. Then you need to scout potential candidates (likely using automated probes), which would take about a century even for just the nearest stars...
While all this is certainly doable, it's really not all that attractive given that you instantly "lose" the colony anyway simply due to the distances involved.
I agree there isn't much benefit to a civilization of creating a colony too far away to be able to effectively communicate with (apart from the philosophical benefits of 'not putting all your eggs in one basket'). The isolation might be very attractive to some colonists though. Just as the pilgrim fathers sailed to america to escape religious persecution and start a new society. Whether a group smaller than a state or civilization would have enough resources to do this is another matter.
A civilisation with advanced enough technology and (by our standards) infinite amounts of time and resources could indeed have groups of individuals seeking exactly that.
Still a far cry from founding galactic empires, but a reasonable motivation that I haven't really considered thus far.
Such reasons for expanding outwards would, however, match our observations (or specifically lack thereof) perfectly: groups that seek isolation or refuge from their parent civilisation likely wouldn't bother broadcasting their existence to everyone or build easily detectable solar system-scale mega-projects like Dyson Swarms.
Reaching a conclusion with so many unknowns (specially unknown unknowns) is risky.
That life must evolve in enough number of planets doesn't mean that the next one is close. And that interplanetary travel is practical doesn't mean that interstellar or intergalactic travel must be. And considering the speed of our current technological development, vs the time needed to get to the next stage in colonization, something big may emerge in the middle. Or something different and unexpected.
In some way, we are like churches deciding what and how a god may think. We are not at the right stage to judge based on our lack of knowledge or perspective. It may not be just one road forward, and going galactic may be the wrong one.
I prefer to take one step at a time, and solve our current roadblocks, if we can. Maybe we have the great filter in front of us in plain view and we can't recognize it.
I agree and I’ve come to the conclusion that the highest moral purpose any intelligent beings can aspire to is to broadcast the information “You Are Not Alone!” by any means available.
At our current stage and philosophy, it may seem that way. That is the point. It may not be valid for most or all of civilizations (if they could be called that way) that are far from us in those and more points.
The same goes for some assumptions behind the great filter concept, like exponential growth and biological needs. Maybe the ideal goal is just a silent self-suficient culture in an small outpost far away from any galaxy.
Yes, maybe civilizations of social biological species that have a relativity low replication rate like us may find contentment with colonizing only a few close star systems. Create a few dense population clusters like our current cities on select planets and space platforms and leave the rest to 'nature'. We already have a declining population growth rate of 1.1 as more people are opting out of starting a family and children due to technological advances and better global socioeconomic conditions. And maybe our current power fantasies of galactic colonization may seem trivial and 'ignorant' to our future generations. One could also call this a great filter. The possibilities are endless and allows one to enjoy it as a bunch of inconsequential thought experiments. Actual problems that require solutions are usually not fun to think about.......
Low fertility among women is not due to desire but to demands of modern society [1]. Women typically desire 2-3 children each. In modern society they can't have them because of low marriage rates and increased employment among women.
Interesting collection of stats, though I don't think the author's conclusions are the only possible interpretation. It's clear that the family size intentions really have been falling since the 60s, and that actual fertility is a fraction of that, which is unsurprising. The bigger sorry here, I think, is that the intended family size drops from 3.4 kids to 2.0. Possibly what's happening is that 'high producers' now make four kids instead of ten, bringing down the overall averages. Basically, it would be nice to see how the distributions of kids per woman change over the decades... I expect something at least bimodal, with a shrinking tail.
(Ed: fixed a couple stats, removed a bad statement about quotients. :P )
One problem with the data is that it's hard to know to what extent modern life changes how many kids you want. Meaning: if a woman knows she has to have a full time job, she may only want, or believe she can afford, two or three children. Conversely, I suppose a woman in agricultural setting might want 7-10 children knowing they could help on the farm. It's probably impossible to know what people would want "unconstrained" by reality, and maybe not even meaningful.
Two things I think are true though. First, women have fewer children than they want, even if what they want is declining over time. Second, women who don't want children, or who want children below replacement, won't ever become the majority of the population - at least not for any significant amount of time. Such women will be replaced by women who, genetically or memetically, want more children.
"Such women will be replaced by women who, genetically or memetically, want more children."
That's not necessarily true. The rural population has shrunk significantly, even as rural family sizes tend to be bigger. The kids largely move to cities (following the gigantic trend towards urbanisation, and in responses to economic realities), and then proceed to have fewer kids in the urban context.
If there's a context with high birthrates, you've got to account for replacement rate within the context: there's a tendency for the kids to find their way to other contexts and thus revert to the mean. Insane "quiverfull" people have lots of kids, but it's not clear to me that they manage to keep up the crazy across generations.
> Maybe we have the great filter in front of us in plain view and we can't recognize it.
One candidate, if we take ourselves as the primary example, is biogeochemical crisis following rapid discovery and exploitation of environmental resources or energy reserves without sufficient consideration of the consequences
It seems a bit convenient that every species capable of interplanetary colonization manages to (a) possess world-climate-altering- industrial scale, (b) rest their industrial needs on a resource that threatens their ecosystem, & (c) remain ignorant of the threat until it's too late to do anything about it.
Comparatively speaking, asteroids and/or ice ages being more frequent than expected seems more plausible.
What was critical in parent's comment was the irrecoverability of the civilization, after such an action. Scaling intelligence is more of a repeatable "trial and error" step (as the article puts it, in a biology context).
(d) their previous activities have rendered it way harder to rebuild a technological society
There used to be iron deposits etc. on the surface. They were recovered by pre-industrial societies. Now we are digging deeper and deeper for resources, but once we lose that ability, it's possible we won't be able to regain it.
What do you do once the nuclear power plant's core has melted, the mine is full of water, and there is nobody around who knows what these things are even there for because all the people who did died years ago of old age. You can't read it up either once we've moved our stored knowledge from paper to machines in what the ancient texts refer to as the mythical "US-EAST-2 region".
It's less of an issue with recraftable materials (like iron) and moreso with one-way ones (like petroleum, fissionable uranium isotopes, helium, or some plastics).
Of those, it feels like the only irreconcilable one is scale: e.g. something you need so much of, repeatedly, that no less-efficient substitute is viable.
And of those, geologically-created, carbon-based energy sources (coal, oil) are the primaries that come to mind.
(Also, nitrogen, but I imagine the Haber–Bosch process would survive)
1. it might be covered in sediments requiring expensive movement for little gain (and how do you know where the iron was/is?) and 2. the structures that don't get covered rust away and turn into dust that erosion distributes over large areas. Post apocalyptic societies will be able to salvage iron here and there for a long time, but will it be enough to cover our planet with railways and kick off a new industrial revolution?
Also, the iron was only an example. Coal and other fossil fuels we can only burn once, then they are gone.
Curiously, the ability to alter biomes at a planetary scale is also one of the prerequisites for colonization. The trick then is having sufficient control of industrial processes to 'get it right,' which requires better global decision making than humans have thus far demonstrated.
(The alternative is extreme plasticity, allowing lifeforms to adapt to otherwise hostile atmospheres...)
> (The alternative is extreme plasticity, allowing lifeforms to adapt to otherwise hostile atmospheres...)
We meet that threshold, though. We are extremely adaptive to otherwise hostile environments by virtue of technology, particularly wearable one - from winter jackets to SCUBA gear.
Sure, I don't think there's necessarily a single filter, or that this is it. Just that it's a candidate. Your examples would presumably be much more common.
A species at a similar development level in some other solar system with slightly better societal goals or a need for a specific resource could already be colonizing other planets or asteroids.
Could be intelligence in any form is brought about by some kind of grand antagonistic pleiotropy. By this i mean the genes that develop intelligence in any species infancy, inevitably lead to the conditions for your (a)(b) and (c) later on.
The time between the emergence of procaryotes and the eukaryotes is estimated to be about 1 billion years. Last time I checked the Universe is thought to be 13.8 billion years. That’s just one order of magnitude between these two numbers. I don’t think it’s inconceivable that we’re the first intelligent life form.
The life itself might be an extremely rare event. Multicellular life might be where the first great filter is.
People always say that if life is possible, then there must be a bunch of aliens out in the universe. It may be unlikely, but one has to be first, maybe it’s us? It’s a somewhat comforting thought, I like it.
Life in other galaxies is unlikely to physically leave its own galaxy just given the vast distances involved. Life in our own galaxy takes a number of inputs that take billions of years to produce.
Most theories show that galaxies all started pretty quickly after the big bang. The number of mergers they have had are what is significantly different. When the universe was younger and things were closer mergers appear to have occurred at a higher rate leading to higher rates of star formation. This in turns floods a galaxy with powerful UV light, which in large amounts doesn't seem conductive to life.
Dissolving the Fermi Paradox by Anders Sandberg, Eric Drexler, Toby Ord
> "This result dissolves the Fermi paradox, and in doing so removes any need to invoke speculative mechanisms by which civilizations would inevitably fail to have observable effects upon the universe"
Thanks a lot for that. It seems like an intuitive result to me, but it's great to have a more rigorous analysis, since people so love to trot out the Fermi Paradox and Great Filter as though they're unquestionable facts.
Another way one can look at it, I think, is that if there is about one civilization per galaxy, then there are billions or trillions of civilizations, but practically speaking we might as well be alone.
But there could easily be hundreds or thousands of technological civilizations in the Milky Way, which has a diameter of over 100,000 light years. We wouldn't necessarily have spotted any of them yet, depending on how far away they are, when they exist(ed), what their tech level and orientation is, what's important to them, etc.
The other argument people tend to pile on to try to claim that we should have seen something is the idea of expansion via colonization, or civilizations using enormous resources to broadcast messages, but all of these have there own huge set of problems.
People try very hard to fill gaps in their knowledge even when it's not really possible to do so.
- Alien megastructures visible at long distances are plausibly not a thing, due to material limitations or something.
- But, even very slow expansion into space should have covered the galaxy long ago, so the aliens should be here or in the archaeological record.
A possible explanation for the latter is, what if the aliens are everywhere but they don't go near stars? Once you have a kind of generation ship that can function essentially forever in interstellar space, why would you risk going near a star or whatnot? That would also be consistent with the "dark forest" viewpoint.
Life is a search algorithm for energy utilization. Arguably the only evolutionary benefit of intelligence is the ability to bridge troughs between local optima farther than genetics alone can. It has limits as much as genetics does. We like to think of intelligence as some boundless forever bootstrapping superpower but all growth curves end up being sigmoid. The hard question is are we close to topping out or are we just waiting on the next punctuation in the equilibrium. I think future punctuations will be found in "what comes after intelligence" in the search for increasingly efficient energy utilization?
Every time this sort of thing comes up (the Fermi Paradox, the Great Silence) I like to point out that it says more about the person than the real world. To wit: there is no time or culture in the history of the world where humans have not been in contact with some kind of "otherworldly" intelligence.
Personally, (not that anyone asked) I think we're in quarantine. I think that most intelligent species rapidly reach a peaceful "win-win" equilibrium, that we humans are rare or even unique in our violence, that this is because of some specific but forgotten event (maybe the Younger Dryas, I don't know) that traumatized us and triggered the development of agriculture and cities, that those are degenerate forms of civilization that perpetrate the trauma that leads to our current malfunctions, and that we are essentially in a hospice-type situation vis-à-vis the little green men.
I was more open-minded to this type of argument a few decades ago.
The quality of our sensors - both smartphones held by everyone, and telescopes, satellites and radar by governments has improved exponentially, without a corresponding increase in detection, so I think it's reasonably likely we are not currently in contact with otherworldly intelligence.
Once I made this argument to a friend, and they sent me this xkcd comic.
Unless the aliens stopped showing up because we've developed smartphones, and they were showing up so often in the 1900s because they knew it was their last shot of dorking around with plausible deniability before camera and telecomm tech became mainstream!
How many detections have we had? The camera argument to me is ignorant of how hard it is to get a good picture of something small in the sky. People are constantly taking videos of dots they say was a UFO but it's impossible to identify what they captured.
With respect, have you gone and looked? To me it feels like the folks who present that objection haven't actually gone and checked, they're making an unfounded assumption.
About once or twice a year I lose a day to a youtube hole wherein I go through all the recent videos of {Bigfoot,UFOs,Cryptids,Ghosts} for fun. There's a lot of crap out there, fake videos and hoaxes, but there are more and more very good candidates for "real" videos.
The US Navy just released video of UFOs buzzing jets off the coast, eh?
The US navy videos it's hard to tell what these are.
The picture is so grainy, a lot of the interest comes from the vivid eyewitness accounts.
I have looked at some accounts, for example listened to Lex Fridman interview with one of the Navy pilots.
To me, I need a photographic evidence that isn't some blurry smudge. If you start going down the eyewitness testimony route then you get some evidence for saints/miracles and also ghosts that meets similar criteria.
The phenomena reported in eyewitness statements in the 60s-80s at least some seems possible to capture with satellite/phone camera. It's possible that UFOs more cautious now or government is surpressing this but I take the lack of clear photograpic evidence as a reason to update beliefs.
> there is no time or culture in the history of the world where humans have not been in contact with some kind of "otherworldly" intelligence.
If so, I'm just pointing out that communication with other non-human beings is common to all human cultures. Every culture has people who communicate with angels or spirits or people from the sky or under the ground or some other realm, sometimes those folks are central to the culture, other times they are peripheral. I think our modern rational materialist fundamentalists are the first to seriously posit the idea that humans are strictly alone in the Universe.
> There is zero actual evidence of anyone communicating with any non-human intelligences.
And that is your belief.
Here's a whole documentary about interactions between Brazilian military and something weird:
> In 1977, numerous UFOs were seen in the Brazilian city of Colares, Pará. The UFOs fired light beams at people, causing injuries and sucking blood from 400 witnesses. After a rise in local concern, the mayor of the city requested help from the Air Force.
No no, you see, when a scientismist/materialist believes something, that makes it true. Unlike when anyone else believes anything! What else is "truth" supposed to mean?
"Believe" is the wrong verb here. I believe that the Irish rugby team will one day win the world cup (despite all evidence to the contrary). I accept that the available evidence does not support the hypothesis of non-human intelligences having contacted us (certainly not widely).
It's certainly possible that Earth has been visited or contacted by non-human intelligences. I'd imagine if you have the technology for interstellar travel, it would be pretty trivial to evade detection.
But just because you can't rule it out, doesn't mean it happened.
Also, WTF is a "scientismist"? Is that a typo or a misguided attempt to conflate science with scientism?
(In re: "Operação Prato", yes, it was closed at the time, but then "In 1997, two decades after the operation, Captain Uyrangê gave an interview to Ufologists Ademar José Gevaerd and Marco Antônio Petit where he recounted his experiences living alongside his men." and the video is (in part) about the information in that interview. The Wikipedia entry you link to and which I quote here doesn't go into that. Wikipedia is no higher a bar than Youtube.)
Yes. That page lists sighting of Unidentified Flying Objects. The clue is right there in the name. It's things we haven't identified.
"We saw some weird lights in the sky" does not by any measure equate to "there is no time or culture in the history of the world where humans have not been in contact with some kind of "otherworldly" intelligence."
> Wikipedia is no higher a bar than Youtube.
Wikipedia has its problems, but it's an order of magnitude higher a bar than Youtube. Wikipedia has editors and citations.
Let's take a step back. I feel like we're inadvertently trolling each other.
> > Except you're the one with the extraordinary claim, that's my whole point.
> That's not a point, that's playground "nuh-uh, you stink" level of debate.
No, that's my actual point: Your idea that we are totally alone is newfangled. It's new. It's recent.
I'm not actually trying to convince you that "UFOs are real" whatever that would mean. (If I had proof I wouldn't share it: as I said originally, I think we're in quarantine. Forcing people to confront their neighbors before we're ready would be inhumane. Thus the "Great Silence" or whatever you want to call it.) And you don't seem at all interested in changing your view anyway.
> Wikipedia has its problems, but it's an order of magnitude higher a bar than Youtube. Wikipedia has editors and citations.
Wikipedia is not more authoritative than reality. In this case the video in question is of the primary source, the actual guy who interviewed the Major, reporting on what he learned. The Wikipedia entry doesn't include this new information.
But again, I'm not actually trying to convince you. I'm just pointing out that the idea that we haven't had interactions with "little green men" of various kinds is a new idea and that it says more about the person who believes that idea, that they believe that idea, than it does about the contents of the real world, where, in fact, lots of people do not believe that idea and many have had experiences that have contradicted that idea.
> I think that most intelligent species rapidly reach a peaceful "win-win" equilibrium, that we humans are rare or even unique in our violence
This reminds me of a short story where Earth exists in a Bermuda Triangle-like sector of space, known as the Veil of Madness, that all other civilizations avoid: https://creepypasta.fandom.com/wiki/Mankind
Even in the absolute worst case scenarios, climate change doesn’t wipe out humanity. Life would be very different (and would frankly suck), but some humans would still survive.
The question is how long it takes to get back to our current level (hopefully with lessons learned!)
Yes we are probably not wiped out, but the current trajectory will bring us to a hot earth scenario. This will limited humanity (and most current life) to the pole regions or fully controlled closed environments as everything to close to the equator will be too hot for life.
Under these circumstances we will be unable to become as space faring species.
The worst part is that the hot earth is a stable system and returning to the our current state will take millennia.
Geoffrey West's work on the laws of life and metabolism might provide some insight. He shows that adaptations tend toward crashes so that survival requires constant ongoing adaptation to avoid self disruption. This means it is highly likely that advanced civilizations will tend to crash whether it is from their own consumption of resources or catastrophic changes that go beyond capacity for adaptation.
"Life Will Colonize""So far, life on earth seems to have adapted its technology to fill every ecological niche it could."
Not any more. As technology has advanced, and agriculture has become less labor intensive, there's been a sizable cutback in populated area in the US and Japan, at least. Farms in less productive areas are not competitive and those areas are emptying out.[1] Towns which serviced the farms are dying off with them.[2]
Colonizing and terraforming every single rock in the solar system increases the available land only by a factor of three: https://xkcd.com/1389/
There's just no way every commoner gets their own Caribbean cabin. Unless we find some unlikely physics hack in the last few vestiges of scientific unknowns, any interstellar travel seems impossibly difficult.
An alternative future: we live forever as brains in the vats, plugged into infinite virtual worlds devoid of scarcity, life-threatening danger or physical constraints. Most of the human activity takes place there, with occasional interactions between the virtual and the real. No new physics required, just a series of incremental improvements in biology and computing.
If we're being cynical, it's trivial to ensure that every commoner gets their own Carribean cabin - just reduce the number of commoners by a few orders of magnitude. After all, with some technological advancements, you would not need huge numbers of commoners just for their labor.
A stable future can plausibly take many forms, not all of them are nice.
The thing I keep seeing people miss is the narrow slice of time that we have existed in a technological state to be broadcasting and/or looking. Assuming exponential distribution, this is most likely to only last further as long as it has already. And with us as the only example, it would most likely be the same for others. So 50 years out of 5 billion on the planet and 3 billion since life began. Are there 100M stars within radio range? Do we even have time to point antennas at each one long enough to get a signal? That’s about 15 seconds each. How many bands do we need to scan in that time?
Any hope of contact or expansion requires an extremely long period of sustainable existence in a state of constant technological development. Most of modern humanism is antithetical to this. The entire world today seems focused on expanding consumption. This is especially true of both colonialism and immigration. Economist today judge an economy by its internal consumption rather than older notions like export productivity. Seems like we’re going to have to reconsider policies and priorities if we want to make it out of here.
I don’t think there is a singular great filter. Instead I suspect there is a relatively constant probability of a black swan event across the entire existence of a biosphere.
It took over four billion years to get from simple replicators to what exists here now. It is quite possible that most biospheres simply don’t make it that long without such an event.
We don’t know the probabilities, but over billions of years the continuous probability of biosphere extinction need not be very high to filter out almost all biospheres before they develop something capable of interstellar signaling or flight.
Keep in mind that another prior we don’t know is the probability of a diverse biosphere developing this type of intelligence. We have no idea if that is likely or not even given sufficient time and energy inputs.
Intergalactic flight is many orders of magnitude harder than interstellar flight, which in turn is many orders of magnitude harder than interplanetary flight. If the probability limits such intelligences to no more than an average of 1-2 per galaxy then there is your answer. We would be extremely unlikely to see intelligent aliens any time soon, even if we do find a lot of microbes.
Given where Earth is now I would be surprised if it does not hatch an interstellar scale intelligence at some point in the remainder of its habitable life. Will that be us? Hopefully so. Given that we are already almost there (on evolutionary time scales) it is reasonably likely it will be us or an AI we create.
I think the "great filter" is evolution itself. Life formed almost immediately that the conditions allowed for it.
But it took over three billion years of relative stable conditions for it go go past the stage of single celled organisms and even the cell itself took a long time to form. Higher forms of life are only 500 million years old and the human line only started taking shape the last few million years.
Personally I think the universe is teaming with life but intelligent/sentient life is exceedingly rare.
While those things are indeed dumb, all forms of human stupidity including wars have killed at most a few percent of any generation. At the Great Filter scale, those aren't a significant evolutionary pressure.
I sometimes think of how Earth is so OLD. It’s a third of the age of the Universe. That is just mind boggling. While I have trouble mentally grasping ages on the magnitude “billions”, I do know what a third is. It’s a very sizable chunk. And for this very old thing with life as you say very early — it’s crazy how we’re here only now. The sample size is small though. I have no idea if quirks on the path took evolution unusually long or if we’re early, or what. Still, yes, this is something to consider.
Even more mind boggling, in Canada you can find bedrock that is 4.28 billion years old and have survived bombardments, erosion and plate tectonics. I'd like to have one of those rocks one day :)
In my country (Norway) the oldest rock is "only" 3 billion years old, life was well underway at that time.
Or we just can't detect any, and neither can they. Space is incredibly vast, and interstellar travel and communication might actually be insurmountable obstacles.
We're really optimistic about it, dreaming up FTL and stuff, but it may turn out to be just... impossible.
You don't need FTL or anything exotic. On the scale of O(100 million) years, expansion at 0.001c is enough to colonize the galaxy.
A general purpose von Neumann probe is not that far off. Self-replicating micro-machinery and reasonably intelligent robots already seem on the horizon. Unless there's truly some unforeseen roadblock, certainly within 1000 years of current growth. A 1 KG probe at 0.001c takes about 90 gigajoules of energy. On the order of what an Airbus A380 uses at cruising speed.
Given lots of patience, and an only slightly higher level of current technological development, interstellar colonization does not seem like an insurmountable challenge.
I hope you enjoy your 4367 year ride to Alpha centauri. How will you power the probe without fusion and why would anyone be there on earth to check the probe's reports?
1) Our knowledge of physics is still very small. ~20% of the universe is 'dark matter'. All we really know about it is that it falls down. It outweighs the stuff you, I, and the all the stars in existence are made out of by ~4x. The other ~75% of the universe is 'dark/negative energy'. We know even less about it beside that it seems to fall ... up (?). And it's the super majority of what we know it out there. Give it another 200 years, and even this understanding is going to be embarrassingly outdated. Any other civ that is just 10k years ahead of us is going to be working in physics that we can't even imagine.
2) That leads to the larger issue: Time. The difference in our lives and the lives of the earliest humans is literally astronomical, in that we have people living up in space now. That same rate of difference separates us from any neighbors out there. Their understanding of our universe is likely to be so vast that we're essentially amoeba to them. Though intelligent life may exist out there in bushels, we're still infants in what 'intelligent' means. We may be surrounded by olde gods rendering us effectively alone all the same, and those gods themselves surrounded by yet grander deities rendering them alone as well.
Yeah, I'm not saying we are peak intelligence, but it took us almost 4 billion years to reach the point where we even can ask the question "Are we alone?". Much of the early universe had conditions that were not as stable and favourable as the last 4 billion years.
I also think distance and time is preventing us from detecting any other like us, but I'm pretty sure some exists somewhere out there. It's just that the reality of physics (even with more knowledge) prevents easy travel and contacts.
Another thing is that we have barely looked at the sky. The SETI project is very underfunded and most other projects have just recently started looking for planets and signatures that can indicate life (not intelligent life). Many think we have surveyed all of space in as much detail as our current technology allowed but we are _far_ from that.
Humans are doomed to die at the Heat Death of the universe. Science tells us our universe had a definite beginning, the Big Bang, and that this event will not repeat: there will be no Big Crunch, no reboot. SciFi authors prefer to ignore science so they can imagine immortal humans who survive the cycle of infinitely rebooting universes. If we colonize the stars and galaxies we can postpone our death a few trillion trillion years, but eventually the last star will snuff out, the last black hole will evaporate, and there will be no energy left to power the phenomena of intelligence and consciousness, and life shall be no more. The last humans will have to bravely face certain and inevitable death just as our prehistoric ancestors did, and just as you and I must.
That's choosing an arbitrary finite point on an infinite spectrum.
What is beyond the universe? What is beyond time? What IS the universe?
We simply do not know the answers to these questions. Hell, we barely understand what consciousness and sentience is.
Maybe by the time we make it to the heat death of the universe, we will have answered these questions, and can reverse entropy. Maybe not.
But the quest to get these answers and to overcome our elements is what gives us purpose. Everything we do in our mortal lives stuck on the rock of our birth, is in one way or another, in the quest to achieve that.
Some people find that too overwhelming, and choose either religion or nihilism. I think there is a middle ground.
You don't need to fully understand something to know that it will die. I don't need to know what the billions of transistors in a MacBook CPU do in order to understand that the CPU will cease to compute if placed in an incinerator and burned to gas and ash. I don't need to understand how the human brain works in order to understand that it will no longer work when our star balloons to a red giant and incinerates the brain to gas and ash. You don't need to understand things in order to understand that they will end when physically destroyed. Everything in our universe will be physically destroyed at the Heat Death. Time, Space, Matter, and Energy will all end. There is no "middle ground". It will all end. If there is an eternal God who exists outside the universe and who will sustain the immortality of souls, as Plato thought 2400 years ago and all noteable Judeo-Christian philosophers have held, then something of humans will exist after the Heat Death. Otherwise, we know it will all die, and we don't need to know how it works to know that it will die.
Science tells us no such thing, and when you're talking the ultimate fate of the universe then there is no consensus, just different theories. There's the big freeze, the big rip, the big crunch... all manner of ideas. Then there is the universe itself. Well what is that? What about multiverses etc?
Just to take one such theory emerging from heat death ideas. Once the fundamental touchstones of mass and structure disappear, scale also disappears. The infinitely large universe becomes physically identical to an infinitesimal one, and is reborn in a new Big Bang — with all the mass and energy of the previous universe once again jammed together into a tiny space.
These sort of cyclic cosmology ideas are held by prominent physicists including the recent Nobel prize winner, Roger Penrose.
Like all us, I have no idea what is true but its hardly a closed subject.
Scientific observation has ruled out the Big Crunch. The Big Rip happens in the remote future if the equation of state parameter w is less than -1, where w is the ratio of dark energy pressure to its energy density. If this is true it is only a minor detail of the Heat Death as far as life within this universe is concerned: all biological life and biological consciousness will end whether the Big Rip happens before the Heat Death or does not happen. (If there is non-biological Life after Death as various religions maintain, then consciousness will survive the Heat Death, but otherwise it will not.) The Conformal Cyclic Cosmology (CCC) of Penrose is speculative and has zero strong empirical evidence to support it. They've studied the CMB but it has made no testable and verifiable predictions. The astrophysics community at large sees the observational inevitability of the end of the universe as we know it: the universe is flying apart and cooling, and nothing can change this.
The universe flying apart and cooling doesn't contradict Penrose, it's part of the theory just to address that point. An infinite structureless, massless universe is a singularity, or so the theory goes.
Assuming this was "settled" (whatever that means in science let alone theoretical physics), mavericks like Penrose are frequently proven right. 'Kuhnian' paradigm shifts are the norm in science, particularly in a field like this. Expect many more...
Penrose's CCC predicts all biological life on our planet and all biological life on all other worlds within our universe will end, just like the conventional Heat Death. To point out this fact - that all biological life is doomed to die - was the purpose of my original post. We can talk about nuclear war, climate change, hostile aliens, and other short term threats to human survival. We will survive these short term threats or we won't. But in the long term it is 100% certain we don't survive. We only survive the Heat Death if it turns out we are living in a Matrix of sorts and the computers of the Matrix are hosted in a datacenter universe that is truly eternal, unlike our universe which will die the Heat Death. Or we survive the Heat Death if there is an eternal God who gives us a post-biological existence after the Death of our universe. My point is that present humans and far-future humans are in the same boat as prehistoric humans: we all must learn to face death bravely. Future humans will never have permanent biological immortality, because our universe does not allow it. Neither does Penrose's universe. Furthermore, Penrose's only testable prediction (CMB concentric rings caused by past reboot of universe) proved unable to be replicated by three independent attempts. Einstein's theory in contrast said the orbit of the planet Mercury should have an observable precession if true: so we pointed our telescopes at Mercury and lo, Mercury did indeed precess just as his set of equations said it would.
Sure we will all die, assuming humanity was alive at the end. To be specific about my objection, you said that this event will not repeat and I'm saying, I'm not sure and neither are certain others. An eternal recurrence is not ruled out. Nothing would survive a reboot though, sure.
To be clear, assuming there was an infinite reboot sequence I'm not saying that there would be life again, let alone intelligent life. I'm just making a statement on the fate of the universe.
While it's difficult to imagine a scenario in which humanity extinguishes itself, it's easy to imagine scenarios which make civilized society difficult, and could preclude future advanced civilizations from ever emerging on Earth, these may constitute a variety of "hidden filters" which make exiting ones own solar system or mustering the energy to make oneself known impractical.
The article makes reference to a million year time horizon, however even earthly nuclear energy reserves may become strained on a thousand year time horizon. As we're all acutely aware, the great biochemical battery of fossil fuels is already operating on diminished capacity. Planet's such as mars lack the hydro-cycle to drive renewables, the organic legacy to support fossil fuels, and potentially the tectonics to enable surface extraction of nuclear fuels.
While a theoretical expansion outside of the confines of earths gravity to acquire resources from asteroids, or produce high concentrations of solar energy is currently achievable on a 20-100 year time horizon, supporting the energy demands of the aerospace supply chain or considering regular space launches may be difficult in 2 centuries. On a thousand year time horizon it's entirely plausible that maintaining a purely renewable economy makes the production of certain materials impractically expensive when considering the concentrated energy demands of blast furnaces or industrial mining.
Similar collapse events have occurred historically due in part to the exhaustion of limited resources such as forests have occurred in the past in both Europe and polynesia. If a similar event occurred in the future it's entirely plausible that a future civilization would be unable to muster the resources to ever "unlock" the next set of energy production capabilities.
Scenarios where humanity extinguishes itself are easy to come by: We are still living under the threat of accidental or intentional launch of a great number of nuclear weapons. The remaining civilizations might be unable to survive or thrive with what's left.
On the other hand speculating about the technological limits of humanity a million years in the future is difficult when we've only come up with nuclear energy a few decades ago, and while progress in some areas has been overdue, generally there seem to be quite a few "research trees" with potential for scifi-tech.
Industrialization would be slower without fossil fuels, but that doesn’t mean it can’t happen. Small scale wood smelting can eventually make way to hydro powered electric based smelting.
We are used to a very energy extensive economy, but most of the world would be habitual without any home heating or cooling for example. Similarly, a network of street cars need something like 1% of the energy as individual cars for everyone in a city. Historically, rivers, streams, and canals where similarly quite efficient long distance transportation networks we have largely forgotten about.
Like you say, there are enormous amounts of low-hanging fruit when it comes to energy efficiency across all of society.
Take building insulation, for example. Where I'm from, triple glaze windows were made mandatory 30 years ago, every single existing apartment building was forced to retro-fit. Yet when I moved to the US less than ten years ago, apartment ads would regularly highlight "DOUBLE GLAZING" as if that was some incredibly expensive and luxurious feature.
Also where I'm from, I used to own an apartment in a building from the 1940s. But a bit more than ten years ago, new strict energy efficiency requirements went into effect, so my building - and every building like it in the country - had to fix it, often by adding a thick layer of insulation on the outside.
I still own an apartment there, it's newer, but the outside walls are 30cm thick and made of concrete for insulation purposes. And yet, here in the US, I regularly see new housing construction that's essentially just plywood for every single wall, inside and outside.
The US is incredibly behind when it comes to insulation and energy efficiency, because the economics of it doesn't make sense. If energy were to become much more expensive, this would change pretty damn fast.
There's also a US approach to 'grandfathering' in existing structures as building codes are updated. The only time I will ever 'have' to bring something in my house up to date is if I voluntarily do something like open a wall or install a new HVAC unit. And then the only thing impacted is that item, nothing else even gets inspected for safety/compliance.
I understand it to some extent: TONS of people can't afford to just...replace all of their windows, for example.
I live in an early 1800s farmhouse which has had a lot of work done on it over the years--to code--and has had new top-of-the-line windows put in as well. But if the whole house suddenly had to be fully compliant with modern code? You'd probably just need to tear it down and start from scratch. I'm sure that's true on tons of houses, especially in older areas of the country.
As far as I understand it, retrofits were only forced on commercial landlords, co-ops, and condominium buildings. Private home owners weren't forced, but there's incentives and tax relief for improving the energy efficiency of your house instead.
New construction, apartment buildings and single-family homes alike, all have to abide by the same updated rules.
It's really difficult to "extinguish" all human life. Even in a full nuclear exchange between all major nuclear powers, places such as patagonia, and new zealand will likely be unscathed. Particulate matter does not generally cross the border between the northern and southern hemisphere and the vast majority of weapons will be detonated in the northern hemisphere. This doesn't include the countless habitable islands with the potential to sustain reasonably sized villages.
A similar story exists for bio-weapons and other means. It's definitely possible to end civilization today, but such technologies are unlikely to end humanity - worst case, rehabitation of the main continents takes 1-2 centuries for the worst fallout to decay and enable farming.
While I don't subscribe to the view, there is modest evidence that scientific progress behaves like any other process of discovery - as a series of S curves where early progress is slow but speeding up every year, followed by a spike of progress and ultimately a steady period of diminishing returns.
The US has an interesting problem right now. Wild hogs are wreaking utter havoc and we don't have effective means to control their population. I'm fairly confident that humans will win that battle. But what if we nuked population centers? Most of the hogs would survive, but only a fraction of the humans. Who would win out in the decades to come? Hogs can eat all sorts of roughage, survive out in the elements, etc., humans are much more dependant on their technology. Want crops? Sorry, hogs ate 'em. Wanna eat hogs? They're smart, and after your ammo stores are depleted, you're back to the stone age.
But the question isn't mere survival -- can intelligent life thrive to the point where we can achieve interstellar travel?
I think you’re underestimating Stone Age humans, we used to hunt freaking lions and other big cats with stone tools. We started causing mass extinctions long before industrialization.
I'm not underestimating stone age humans -- I've spent much of my life learning and using stone age skills. Not enough that I can actually live as a stone age human, mind, and there's the rub. In that learning, I've met a very small number of folks (like [1]) who are actually equipped to survive a stone age. Judging by my experience, by watching other "good" students in those classes... with good training by masters, we still fail hard on our first few times out. And we're well-fed, moderately well-equipped, and not suffering from radiation poisoning.
The real question isn't "how badass were stone age humans", it's "can the smartphone generation re-invent stone age technology quickly enough to survive"?
It would probably incredibly brutal and many would die early on, but as long as enough people survived the initial transition and found some sort of stability, humanity would carry on. Even if conditions were generally terrible, just a few areas where the survivors can grab a toehold could be enough. The prospect of a grim, untimely death for yourself and everyone you love would be rather motivating.
This sounds like a great premise for a novel, and the question could be explored at a quite deep level. Consider that most ecosystems are now codependent on human civilization, and many locales do not have the necessary flora or water availability to support stone age civilization.
There are certainly some ecosystems such as fishing communities north of Vancouver that would do well and be shielded from any nuclear exchange, but the wild deer population in Massachusetts would likely not be sufficient for any significant number of modern stone age men to survive.
I recommend the anime Dr Stone which answer the inverse question:
can a smartphone generation, put in a stone age world, re-invent modern technology quickly enough to survive"?
Tribes are how humans survive. What we think of as "survivalism"-- a single person getting by alone in the woods-- wouldn't work in any era with any technology.
There weren't very many humans in the world back in the stone age. With a future catastrophe, there will be so many people that there will be a lot of them way out on the tail of the distribution, whatever is selected for.
Going by the how to make everything series I am 100% confident a million people with a smartphone with an offline copy of wikipedia and a single solar farm to charge them could rebuild human society within a lifetime to 15th century level with some early elements of industrial machinery. The few centuries after that are quite insignificant.
You can very much use solar panels on Mars. There's also a clear advantage that right now, there's nothing on Mars, lots of land to place said solar panels, but IMO, that's not going to be an issue. We will probably master nuclear fission within the next few decades. Lots of progress has been made, and it will solve our energy needs. What if we run out of deuterium or tritium? Not a problem, by that time, in a few centuries, we'll likely be able to build bigger, better reactors that can fuse "normal" hydrogen and maybe even helium.
As for the great filter, I've always thought that the real danger is something that would cause say, one person, to have an outsized destructive power. Imagine if we successfully invent nanobots that can self-replicate, for example, and anyone with the right set of skills could program them. In that scenario, it's within the capability of any individual to create a deadly disease. You just need one unhinged person to trigger a horrible disaster. Nanotech could be much more dangerous than nukes, and if you combine strong AI and nanotech, I could see that being an immense survival risk.
Martian solar energy production has a few "unique" challenges. Including
- Dust
- Supply chain
- ~40% less watts/square meter
Of these the most unproven is the supply chain problem. The link below summarizes why solar doesn't work in the short-term for mars habitation missions - it's an open question as to whether there are economically extractable deposits of silicon, cadmium, and other materials to build out a solar farm. Bear in mind, terrestrial resource extraction makes extensive use of water.
The comparison would be for locally produced solar. We know that making solar panels on Earth is a net positive energy expenditure, from raw materials to recycle/disposal, and just barely so. But the cost of creation of solar panels on Mars is unknown relative to net energy expenditure. I'm fairly certain that it would be many decades, if not centuries, before it became net positive. Sending solar panels to Mars is obviously not a good use of Watts.
I don't think it's that bad. The SpaceX Starship should be able to carry ~125 metric tons to Mars, and there will be cargo-only variants. You could ship ultralight flexible solar panels in each Starship. Even if it's 40% less energy than on earth, I would say that's still not bad. You could easily fit enough panels to get a 100KW array in 10 metric tons of payload. You use the batteries from the ship itself to store the power for night time. If each cargo Starship can bring one such array, then you will pretty quickly have a megawatt of power generation. It's not huge, but if you pay attention to energy efficiency, it's enough to power tools to dig, lighting, heating, rovers, etc.
As for dust, the Mars rovers have shown it's not a real issue, wind removes most of it, and if we actually have people there, we can occasionally clean the arrays too.
Would I rather bring a nuclear reactor to Mars? Sure, but I also think we can make it work with just solar if we have to.
The most proven problem of solar is dust storms: “dust storms which can obscure the sun for weeks at a time, thereby rendering solar panels highly ineffective” without another complementary energy source (wind? energy storage?) see https://www.nasa.gov/centers/ames/news/releases/2001/01_72AR...
> While it's difficult to imagine a scenario in which humanity extinguishes itself
I used to believe this, until the pandemic. Now I think bio weapons are infinitely more dangerous than nukes. Imagine if COVID was a few times more contagious and as deadly as it's close relatives SARS and MERS. Not a big stretch really.
We would be pondering extinction right now. If the power was still working.
While the COVID-19 pandemic has struck hard in some countries, it has not been on a scale which threatens humanity in any form? Excess deaths for 2020 are in the ranges 10-300 per 100k, meaning under 0.3% in the worst case.
https://www.economist.com/graphic-detail/2020/07/15/tracking...
Not that pandemics cannot be properly devastating. During the bubonic plague up to 50% of the population died in many areas across the world. It was still no threat to humanity though.
A pathogen as deadly as the plague and as mysterious or intractable to medicine as the plague was in the 1200's released into a connected world such as ours would have an astonishing impact.
The threshold that matters isn't extincting humanity, but collapsing modern technological civilization. That's much easier to do.
The current pandemic revealed how fragile our supply chains are, and I still consider it a small miracle that the impact so far was so small. Lots of people are in dire straits, yes, but the world structurally didn't change much.
Perhaps first deploy a highly contagious virus specific to humans that causes infertility but otherwise no symptoms. That would spread widely before detection. Followed by a highly contagious deadly pathogen that can be transmitted by any mammal: a vector that will kill tribes in remote forests that are out of contact with civilisation.
> even earthly nuclear energy reserves may become strained on a thousand year time horizon
No, they won't. Even if we restrict to just fission power, on a thousand year time horizon we can expect thorium reactors and extraction of uranium from seawater, which multiplies the available energy by a factor of at least a thousand.
Furthermore, on that time horizon we can expect fusion to be available, and deuterium from seawater multiplies the available energy by a factor of about a billion.
Not to mention that on a thousand year time horizon, we should be making full use of the available solar energy in Earth's vicinity by means of orbital power stations, in which case we won't even need any other energy source on that time horizon except for specialized uses like fast spacecraft.
> On a thousand year time horizon it's entirely plausible that maintaining a purely renewable economy makes the production of certain materials impractically expensive
And it also makes it practically certain that any material that's that expensive to produce won't be needed anyway, since cheaper substitutes will be found.
"Limited resources" by itself simply doesn't strike me as a plausible Great Filter.
What if there is unlimited number of The Great Filters. What if we are already Nth contingency plan seeded on Earth by N-1th parent life form(s) woring about the same problem - to survive, replicate further onto closest places as N+1 backup.
> among the billion trillion stars in our past universe, none has reached the level of technology and growth that we may soon reach.
May soon reach? I doubt it. I'd say there's a significant filter between our technology level and large-scale inter-solar-system colonization. It's not at all clear that there is a strong motivation for that - except for a continuous-growth economy, which is kind of unsustainable anyway. Once the population stabilizes and human civilization is basically energy-neutral (i.e. not taking more than the sun provides), where's the great need to colonize someplace else (as opposed to communicating)? And if we don't stabilize - civilization will burn itself out soon enough, colonization or no.
> Even if life only evolves once per galaxy, that still leaves the problem of explaining the rest of the filter
No it doesn't. It's extremely unlikely that one planet with life will travel to a different galaxy. Even with intelligent life it's extremely unlikely. Only if instantaneous travel were possible would this be likely.
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[ 3.9 ms ] story [ 247 ms ] threadHistorically, it has been an advantage to have a strongly tribal drive. Cohesive groups achieved much more than individuals and yet were small enough that they could effectively self-police and agree on common goals.
However, as the capabilities of each tribe increased and the world became smaller through travel (and now the internet), tribalism, us-versus-them still remain part of our basic instincts and subconscious, however it is now the source of international and high powered conflicts.
10000 years ago, our tribal programming resulted in the survival of a group of families and the development of townships and emergence of societies. If a tribe got particularly bloodthirsty, their impact was almost purely local and perhaps eventually their notoriety resulted in a decline.
Now, sticks and stones have been replaced by nuclear weapons and ICBMs. A first strike capability is no longer dangerous to just one village, but entire continents.
Perhaps our technological evolution has outpaced our biological and social evolution, and the behavior that was optimal even 1000 years ago is now a grave danger?
Any intelligent organism will have to overcome the biological local optima that brought it to the intelligent state before further developing as a species.
We already have explored a variety options, each with their own advantages and downsides:
1. Free individuals in a distributed system in a cottage industry economy.
2. Semi-free individuals who gather in tribes formed around value-generation (i.e. corporations).
3. Centralized system with individuals who are assigned functions.
Future progress will have to be technological and will change what it means to operate in the afore-mentioned scenarios 1,2,3.
Our current biggest challenge is to make ourselves 'smarter' (i.e. less susceptible to the biases baked into our DNA). Otherwise, it's likely only a matter of time before we cripple ourselves into an extended Dark Age or worse. Constant setbacks resulting from too many of us having ignorant, emotional reactions to incomplete stories with insufficient facts means we're all dancing on shifting sand. It's not a good foundation upon which to build a durable interstellar civilization.
In many cases the promiscuous nature of information works heavily against human welfare. One aspect of that is that incorrect information spreads as well -- sometimes better-- than correct information.
People have been able to share incredibly stupid ideas with high efficiency even before the social media.
How do you decide which is which?
That is definitely a credible theory, and it's currently catalogued as number 2.2 on Wikipedia's list of hypothetical explanations for the Fermi Paradox, where it is given the haunting title: "It is the nature of intelligent life to destroy itself".
https://en.wikipedia.org/wiki/Fermi_paradox#It_is_the_nature...
This explanation is much more plausible than a Great Filter. Here's a great comment summarizing the argument very intuitively:
https://news.ycombinator.com/item?id=17562439
I also found this one very helpful:
https://news.ycombinator.com/item?id=17564379
The paper argues against this in that you don't need a few very improbable. In fact, there are many parameter choices where none of the probabilities in the Drake equation are particularly low, yet the resulting number of intelligences is still staggeringly small.
tl;dr: All parameters can be a bit lower. Then you don't need any events that are extremely improbable.
Isn't that just elaborated way of saying that some of the parameters of the Drake equation have to be much smaller than we think?
Let's use the simple example you reference from the paper. If we just use the mean as point estimates, then indeed we obtain an extremely low probability that there's no other intelligences:
However, there is already a 82% chance of an empty galaxy if the parameter p is halved: Now of course halving every probability is a lot, however now there's no single or few events that have a very low probability of happening. The Great Filter disappears.See also my other comment here: https://news.ycombinator.com/item?id=25811359
Also: The Drake equation has one factor which is the avg number of planets per star, of which we are already quite confident it is above 0.1.
I don't see how it's any different from the great filter explanation. It's just great filter with statistical distributions.
However, as per my other comments, you can update the distributions of your parameters in different ways, such that none of the events in the Drake equation have a particularly low probability.
Then the Great Filter disappears and there's no specific or few set of events to point to - it's just that the probability of all events succeeding in combination is extremely low.
The probe is near Pluto, and so able to sky 10 times darker than Hubble, but isn't observing the modelled galaxies extrapolated from Hubble observations.
https://www.foxnews.com/science/nasa-finds-fewer-galaxies-th...
For example, it explains why the sky would be darker from the POV of Pluto than the POV of Earth orbit (Zodiacal dust is relevant at this level).
That said, I’m still surprised that the estimate was ever as high as 2 trillion; I thought the estimate had been the lower 100 billion value for most of my life.
* https://www.youtube.com/watch?v=UjtOGPJ0URM
This video by Kurzgesagt explains it well: https://www.youtube.com/watch?v=ZL4yYHdDSWs
Outside of the very nearest neighbouring systems, any interstellar colony would instantly become an isolated new civilisation. There's simply no plausible way for interstellar trade or even just meaningful communication.
All a colony at say, 82 Eridani - a sun-like star about 20 ly from Earth, would have a two-way communication time of 40 years. Even digital "goods" aren't worth exchanging if it takes 20 years to send them and another 20 years to receive any kind of payment.
At a very optimistic 30% lightspeed, ships would take 67 years to get there. This means no one can make the journey within a single human lifetime, unless the lifespan is dramatically increased or some form of hibernation technology is used.
In any case, colonists would be completely removed from Earth and all that effort pretty much requires a suitable target planet to be present. Without radical genetic changes, humans wouldn't be able to thrive and survive on a Super Earth or in poisonous atmospheres. So another factor would be spending tens of thousands of years and unfathomable amounts of energy terraforming planets or changing the human genome beyond recognition.
The same issues would apply to extra-terrestrial intelligences as well, which is why I don't think interstellar colonisation would even be all that desirable in the first place.
First you have to find a suitable host star. Next you need to find a matching planet. Then you need to scout potential candidates (likely using automated probes), which would take about a century even for just the nearest stars...
While all this is certainly doable, it's really not all that attractive given that you instantly "lose" the colony anyway simply due to the distances involved.
A civilisation with advanced enough technology and (by our standards) infinite amounts of time and resources could indeed have groups of individuals seeking exactly that.
Still a far cry from founding galactic empires, but a reasonable motivation that I haven't really considered thus far.
Such reasons for expanding outwards would, however, match our observations (or specifically lack thereof) perfectly: groups that seek isolation or refuge from their parent civilisation likely wouldn't bother broadcasting their existence to everyone or build easily detectable solar system-scale mega-projects like Dyson Swarms.
That life must evolve in enough number of planets doesn't mean that the next one is close. And that interplanetary travel is practical doesn't mean that interstellar or intergalactic travel must be. And considering the speed of our current technological development, vs the time needed to get to the next stage in colonization, something big may emerge in the middle. Or something different and unexpected.
In some way, we are like churches deciding what and how a god may think. We are not at the right stage to judge based on our lack of knowledge or perspective. It may not be just one road forward, and going galactic may be the wrong one.
I prefer to take one step at a time, and solve our current roadblocks, if we can. Maybe we have the great filter in front of us in plain view and we can't recognize it.
The same goes for some assumptions behind the great filter concept, like exponential growth and biological needs. Maybe the ideal goal is just a silent self-suficient culture in an small outpost far away from any galaxy.
1 - https://ifstudies.org/blog/how-many-kids-do-women-want
(Ed: fixed a couple stats, removed a bad statement about quotients. :P )
Two things I think are true though. First, women have fewer children than they want, even if what they want is declining over time. Second, women who don't want children, or who want children below replacement, won't ever become the majority of the population - at least not for any significant amount of time. Such women will be replaced by women who, genetically or memetically, want more children.
That's not necessarily true. The rural population has shrunk significantly, even as rural family sizes tend to be bigger. The kids largely move to cities (following the gigantic trend towards urbanisation, and in responses to economic realities), and then proceed to have fewer kids in the urban context.
If there's a context with high birthrates, you've got to account for replacement rate within the context: there's a tendency for the kids to find their way to other contexts and thus revert to the mean. Insane "quiverfull" people have lots of kids, but it's not clear to me that they manage to keep up the crazy across generations.
One candidate, if we take ourselves as the primary example, is biogeochemical crisis following rapid discovery and exploitation of environmental resources or energy reserves without sufficient consideration of the consequences
Comparatively speaking, asteroids and/or ice ages being more frequent than expected seems more plausible.
Any process which requires scaling intelligence from competitively local and tribal (or any equivalents) to integrated and planetary will do.
You either pass that test or you fail it. If you fail it, stagnation and eventually devolution beckon.
What was critical in parent's comment was the irrecoverability of the civilization, after such an action. Scaling intelligence is more of a repeatable "trial and error" step (as the article puts it, in a biology context).
There used to be iron deposits etc. on the surface. They were recovered by pre-industrial societies. Now we are digging deeper and deeper for resources, but once we lose that ability, it's possible we won't be able to regain it.
What do you do once the nuclear power plant's core has melted, the mine is full of water, and there is nobody around who knows what these things are even there for because all the people who did died years ago of old age. You can't read it up either once we've moved our stored knowledge from paper to machines in what the ancient texts refer to as the mythical "US-EAST-2 region".
Of those, it feels like the only irreconcilable one is scale: e.g. something you need so much of, repeatedly, that no less-efficient substitute is viable.
And of those, geologically-created, carbon-based energy sources (coal, oil) are the primaries that come to mind.
(Also, nitrogen, but I imagine the Haber–Bosch process would survive)
Also, the iron was only an example. Coal and other fossil fuels we can only burn once, then they are gone.
(The alternative is extreme plasticity, allowing lifeforms to adapt to otherwise hostile atmospheres...)
We meet that threshold, though. We are extremely adaptive to otherwise hostile environments by virtue of technology, particularly wearable one - from winter jackets to SCUBA gear.
A species at a similar development level in some other solar system with slightly better societal goals or a need for a specific resource could already be colonizing other planets or asteroids.
The life itself might be an extremely rare event. Multicellular life might be where the first great filter is.
> "This result dissolves the Fermi paradox, and in doing so removes any need to invoke speculative mechanisms by which civilizations would inevitably fail to have observable effects upon the universe"
https://arxiv.org/abs/1806.02404
But there could easily be hundreds or thousands of technological civilizations in the Milky Way, which has a diameter of over 100,000 light years. We wouldn't necessarily have spotted any of them yet, depending on how far away they are, when they exist(ed), what their tech level and orientation is, what's important to them, etc.
The other argument people tend to pile on to try to claim that we should have seen something is the idea of expansion via colonization, or civilizations using enormous resources to broadcast messages, but all of these have there own huge set of problems.
People try very hard to fill gaps in their knowledge even when it's not really possible to do so.
- Alien megastructures visible at long distances are plausibly not a thing, due to material limitations or something.
- But, even very slow expansion into space should have covered the galaxy long ago, so the aliens should be here or in the archaeological record.
A possible explanation for the latter is, what if the aliens are everywhere but they don't go near stars? Once you have a kind of generation ship that can function essentially forever in interstellar space, why would you risk going near a star or whatnot? That would also be consistent with the "dark forest" viewpoint.
Personally, (not that anyone asked) I think we're in quarantine. I think that most intelligent species rapidly reach a peaceful "win-win" equilibrium, that we humans are rare or even unique in our violence, that this is because of some specific but forgotten event (maybe the Younger Dryas, I don't know) that traumatized us and triggered the development of agriculture and cities, that those are degenerate forms of civilization that perpetrate the trauma that leads to our current malfunctions, and that we are essentially in a hospice-type situation vis-à-vis the little green men.
So, um, there? Have a nice day y'all.
The quality of our sensors - both smartphones held by everyone, and telescopes, satellites and radar by governments has improved exponentially, without a corresponding increase in detection, so I think it's reasonably likely we are not currently in contact with otherworldly intelligence.
Once I made this argument to a friend, and they sent me this xkcd comic.
https://xkcd.com/1235/
The tin foil always finds a way.
How many detections have we had? The camera argument to me is ignorant of how hard it is to get a good picture of something small in the sky. People are constantly taking videos of dots they say was a UFO but it's impossible to identify what they captured.
With respect, have you gone and looked? To me it feels like the folks who present that objection haven't actually gone and checked, they're making an unfounded assumption.
About once or twice a year I lose a day to a youtube hole wherein I go through all the recent videos of {Bigfoot,UFOs,Cryptids,Ghosts} for fun. There's a lot of crap out there, fake videos and hoaxes, but there are more and more very good candidates for "real" videos.
The US Navy just released video of UFOs buzzing jets off the coast, eh?
The picture is so grainy, a lot of the interest comes from the vivid eyewitness accounts.
I have looked at some accounts, for example listened to Lex Fridman interview with one of the Navy pilots.
To me, I need a photographic evidence that isn't some blurry smudge. If you start going down the eyewitness testimony route then you get some evidence for saints/miracles and also ghosts that meets similar criteria.
The phenomena reported in eyewitness statements in the 60s-80s at least some seems possible to capture with satellite/phone camera. It's possible that UFOs more cautious now or government is surpressing this but I take the lack of clear photograpic evidence as a reason to update beliefs.
> there is no time or culture in the history of the world where humans have not been in contact with some kind of "otherworldly" intelligence.
If so, I'm just pointing out that communication with other non-human beings is common to all human cultures. Every culture has people who communicate with angels or spirits or people from the sky or under the ground or some other realm, sometimes those folks are central to the culture, other times they are peripheral. I think our modern rational materialist fundamentalists are the first to seriously posit the idea that humans are strictly alone in the Universe.
FTFY
There is zero actual evidence of anyone communicating with any non-human intelligences.
And that is your belief.
Here's a whole documentary about interactions between Brazilian military and something weird:
> In 1977, numerous UFOs were seen in the Brazilian city of Colares, Pará. The UFOs fired light beams at people, causing injuries and sucking blood from 400 witnesses. After a rise in local concern, the mayor of the city requested help from the Air Force.
https://www.youtube.com/watch?v=ThkmRsEBOY0
It's certainly possible that Earth has been visited or contacted by non-human intelligences. I'd imagine if you have the technology for interstellar travel, it would be pretty trivial to evade detection.
But just because you can't rule it out, doesn't mean it happened.
Also, WTF is a "scientismist"? Is that a typo or a misguided attempt to conflate science with scientism?
Yes. It is what I believe based on the available evidence. Do you have evidence to the contrary? And no, eye witness testimony does not count.
This is science 101. You have made an extraordinary claim. You must back it up with extraordinary evidence.
>Here's a whole documentary about interactions between Brazilian military and something weird
I completely believe that people saw UFOs, in that they saw Unidentified Flying Objects.
https://en.wikipedia.org/wiki/Opera%C3%A7%C3%A3o_Prato The investigation was closed after finding no unusual phenomena.
I suggest you raise your bar for evidence higher than "random youtube video"
https://en.wikipedia.org/wiki/List_of_reported_UFO_sightings
That page goes on and on.
(In re: "Operação Prato", yes, it was closed at the time, but then "In 1997, two decades after the operation, Captain Uyrangê gave an interview to Ufologists Ademar José Gevaerd and Marco Antônio Petit where he recounted his experiences living alongside his men." and the video is (in part) about the information in that interview. The Wikipedia entry you link to and which I quote here doesn't go into that. Wikipedia is no higher a bar than Youtube.)
That's not a point, that's playground "nuh-uh, you stink" level of debate.
>https://en.wikipedia.org/wiki/List_of_reported_UFO_sightings That page goes on and on
Yes. That page lists sighting of Unidentified Flying Objects. The clue is right there in the name. It's things we haven't identified.
"We saw some weird lights in the sky" does not by any measure equate to "there is no time or culture in the history of the world where humans have not been in contact with some kind of "otherworldly" intelligence."
> Wikipedia is no higher a bar than Youtube. Wikipedia has its problems, but it's an order of magnitude higher a bar than Youtube. Wikipedia has editors and citations.
> > Except you're the one with the extraordinary claim, that's my whole point.
> That's not a point, that's playground "nuh-uh, you stink" level of debate.
No, that's my actual point: Your idea that we are totally alone is newfangled. It's new. It's recent.
I'm not actually trying to convince you that "UFOs are real" whatever that would mean. (If I had proof I wouldn't share it: as I said originally, I think we're in quarantine. Forcing people to confront their neighbors before we're ready would be inhumane. Thus the "Great Silence" or whatever you want to call it.) And you don't seem at all interested in changing your view anyway.
> Wikipedia has its problems, but it's an order of magnitude higher a bar than Youtube. Wikipedia has editors and citations.
Wikipedia is not more authoritative than reality. In this case the video in question is of the primary source, the actual guy who interviewed the Major, reporting on what he learned. The Wikipedia entry doesn't include this new information.
But again, I'm not actually trying to convince you. I'm just pointing out that the idea that we haven't had interactions with "little green men" of various kinds is a new idea and that it says more about the person who believes that idea, that they believe that idea, than it does about the contents of the real world, where, in fact, lots of people do not believe that idea and many have had experiences that have contradicted that idea.
This reminds me of a short story where Earth exists in a Bermuda Triangle-like sector of space, known as the Veil of Madness, that all other civilizations avoid: https://creepypasta.fandom.com/wiki/Mankind
Humanity? Unlikely.
Even in the absolute worst case scenarios, climate change doesn’t wipe out humanity. Life would be very different (and would frankly suck), but some humans would still survive.
The question is how long it takes to get back to our current level (hopefully with lessons learned!)
Under these circumstances we will be unable to become as space faring species.
The worst part is that the hot earth is a stable system and returning to the our current state will take millennia.
2015 https://news.ycombinator.com/item?id=9324566
2009 https://news.ycombinator.com/item?id=597461
Not any more. As technology has advanced, and agriculture has become less labor intensive, there's been a sizable cutback in populated area in the US and Japan, at least. Farms in less productive areas are not competitive and those areas are emptying out.[1] Towns which serviced the farms are dying off with them.[2]
[1] https://www.visualcapitalist.com/u-s-population-change-by-co...
[2] https://en.wikipedia.org/wiki/List_of_ghost_towns_in_the_Uni...
Is that your candidate for the Great Filter?
There's just no way every commoner gets their own Caribbean cabin. Unless we find some unlikely physics hack in the last few vestiges of scientific unknowns, any interstellar travel seems impossibly difficult.
An alternative future: we live forever as brains in the vats, plugged into infinite virtual worlds devoid of scarcity, life-threatening danger or physical constraints. Most of the human activity takes place there, with occasional interactions between the virtual and the real. No new physics required, just a series of incremental improvements in biology and computing.
A stable future can plausibly take many forms, not all of them are nice.
Any hope of contact or expansion requires an extremely long period of sustainable existence in a state of constant technological development. Most of modern humanism is antithetical to this. The entire world today seems focused on expanding consumption. This is especially true of both colonialism and immigration. Economist today judge an economy by its internal consumption rather than older notions like export productivity. Seems like we’re going to have to reconsider policies and priorities if we want to make it out of here.
It took over four billion years to get from simple replicators to what exists here now. It is quite possible that most biospheres simply don’t make it that long without such an event.
We don’t know the probabilities, but over billions of years the continuous probability of biosphere extinction need not be very high to filter out almost all biospheres before they develop something capable of interstellar signaling or flight.
Keep in mind that another prior we don’t know is the probability of a diverse biosphere developing this type of intelligence. We have no idea if that is likely or not even given sufficient time and energy inputs.
Intergalactic flight is many orders of magnitude harder than interstellar flight, which in turn is many orders of magnitude harder than interplanetary flight. If the probability limits such intelligences to no more than an average of 1-2 per galaxy then there is your answer. We would be extremely unlikely to see intelligent aliens any time soon, even if we do find a lot of microbes.
Given where Earth is now I would be surprised if it does not hatch an interstellar scale intelligence at some point in the remainder of its habitable life. Will that be us? Hopefully so. Given that we are already almost there (on evolutionary time scales) it is reasonably likely it will be us or an AI we create.
But it took over three billion years of relative stable conditions for it go go past the stage of single celled organisms and even the cell itself took a long time to form. Higher forms of life are only 500 million years old and the human line only started taking shape the last few million years.
Personally I think the universe is teaming with life but intelligent/sentient life is exceedingly rare.
In my country (Norway) the oldest rock is "only" 3 billion years old, life was well underway at that time.
We're really optimistic about it, dreaming up FTL and stuff, but it may turn out to be just... impossible.
A general purpose von Neumann probe is not that far off. Self-replicating micro-machinery and reasonably intelligent robots already seem on the horizon. Unless there's truly some unforeseen roadblock, certainly within 1000 years of current growth. A 1 KG probe at 0.001c takes about 90 gigajoules of energy. On the order of what an Airbus A380 uses at cruising speed.
Given lots of patience, and an only slightly higher level of current technological development, interstellar colonization does not seem like an insurmountable challenge.
10-20 generations and it will most likely be all but forgotten. Zero impact on our solar system. Might as well be a story in a videogame.
Perhaps it would be worth it if we worked on extending our lifespans first.
1) Our knowledge of physics is still very small. ~20% of the universe is 'dark matter'. All we really know about it is that it falls down. It outweighs the stuff you, I, and the all the stars in existence are made out of by ~4x. The other ~75% of the universe is 'dark/negative energy'. We know even less about it beside that it seems to fall ... up (?). And it's the super majority of what we know it out there. Give it another 200 years, and even this understanding is going to be embarrassingly outdated. Any other civ that is just 10k years ahead of us is going to be working in physics that we can't even imagine.
2) That leads to the larger issue: Time. The difference in our lives and the lives of the earliest humans is literally astronomical, in that we have people living up in space now. That same rate of difference separates us from any neighbors out there. Their understanding of our universe is likely to be so vast that we're essentially amoeba to them. Though intelligent life may exist out there in bushels, we're still infants in what 'intelligent' means. We may be surrounded by olde gods rendering us effectively alone all the same, and those gods themselves surrounded by yet grander deities rendering them alone as well.
I also think distance and time is preventing us from detecting any other like us, but I'm pretty sure some exists somewhere out there. It's just that the reality of physics (even with more knowledge) prevents easy travel and contacts.
Another thing is that we have barely looked at the sky. The SETI project is very underfunded and most other projects have just recently started looking for planets and signatures that can indicate life (not intelligent life). Many think we have surveyed all of space in as much detail as our current technology allowed but we are _far_ from that.
What is beyond the universe? What is beyond time? What IS the universe?
We simply do not know the answers to these questions. Hell, we barely understand what consciousness and sentience is.
Maybe by the time we make it to the heat death of the universe, we will have answered these questions, and can reverse entropy. Maybe not.
But the quest to get these answers and to overcome our elements is what gives us purpose. Everything we do in our mortal lives stuck on the rock of our birth, is in one way or another, in the quest to achieve that.
Some people find that too overwhelming, and choose either religion or nihilism. I think there is a middle ground.
Just to take one such theory emerging from heat death ideas. Once the fundamental touchstones of mass and structure disappear, scale also disappears. The infinitely large universe becomes physically identical to an infinitesimal one, and is reborn in a new Big Bang — with all the mass and energy of the previous universe once again jammed together into a tiny space.
These sort of cyclic cosmology ideas are held by prominent physicists including the recent Nobel prize winner, Roger Penrose.
Like all us, I have no idea what is true but its hardly a closed subject.
Assuming this was "settled" (whatever that means in science let alone theoretical physics), mavericks like Penrose are frequently proven right. 'Kuhnian' paradigm shifts are the norm in science, particularly in a field like this. Expect many more...
To be clear, assuming there was an infinite reboot sequence I'm not saying that there would be life again, let alone intelligent life. I'm just making a statement on the fate of the universe.
The article makes reference to a million year time horizon, however even earthly nuclear energy reserves may become strained on a thousand year time horizon. As we're all acutely aware, the great biochemical battery of fossil fuels is already operating on diminished capacity. Planet's such as mars lack the hydro-cycle to drive renewables, the organic legacy to support fossil fuels, and potentially the tectonics to enable surface extraction of nuclear fuels.
While a theoretical expansion outside of the confines of earths gravity to acquire resources from asteroids, or produce high concentrations of solar energy is currently achievable on a 20-100 year time horizon, supporting the energy demands of the aerospace supply chain or considering regular space launches may be difficult in 2 centuries. On a thousand year time horizon it's entirely plausible that maintaining a purely renewable economy makes the production of certain materials impractically expensive when considering the concentrated energy demands of blast furnaces or industrial mining.
Similar collapse events have occurred historically due in part to the exhaustion of limited resources such as forests have occurred in the past in both Europe and polynesia. If a similar event occurred in the future it's entirely plausible that a future civilization would be unable to muster the resources to ever "unlock" the next set of energy production capabilities.
On the other hand speculating about the technological limits of humanity a million years in the future is difficult when we've only come up with nuclear energy a few decades ago, and while progress in some areas has been overdue, generally there seem to be quite a few "research trees" with potential for scifi-tech.
We are used to a very energy extensive economy, but most of the world would be habitual without any home heating or cooling for example. Similarly, a network of street cars need something like 1% of the energy as individual cars for everyone in a city. Historically, rivers, streams, and canals where similarly quite efficient long distance transportation networks we have largely forgotten about.
Like you say, there are enormous amounts of low-hanging fruit when it comes to energy efficiency across all of society.
Take building insulation, for example. Where I'm from, triple glaze windows were made mandatory 30 years ago, every single existing apartment building was forced to retro-fit. Yet when I moved to the US less than ten years ago, apartment ads would regularly highlight "DOUBLE GLAZING" as if that was some incredibly expensive and luxurious feature.
Also where I'm from, I used to own an apartment in a building from the 1940s. But a bit more than ten years ago, new strict energy efficiency requirements went into effect, so my building - and every building like it in the country - had to fix it, often by adding a thick layer of insulation on the outside.
I still own an apartment there, it's newer, but the outside walls are 30cm thick and made of concrete for insulation purposes. And yet, here in the US, I regularly see new housing construction that's essentially just plywood for every single wall, inside and outside.
The US is incredibly behind when it comes to insulation and energy efficiency, because the economics of it doesn't make sense. If energy were to become much more expensive, this would change pretty damn fast.
I understand it to some extent: TONS of people can't afford to just...replace all of their windows, for example.
New construction, apartment buildings and single-family homes alike, all have to abide by the same updated rules.
A similar story exists for bio-weapons and other means. It's definitely possible to end civilization today, but such technologies are unlikely to end humanity - worst case, rehabitation of the main continents takes 1-2 centuries for the worst fallout to decay and enable farming.
While I don't subscribe to the view, there is modest evidence that scientific progress behaves like any other process of discovery - as a series of S curves where early progress is slow but speeding up every year, followed by a spike of progress and ultimately a steady period of diminishing returns.
But the question isn't mere survival -- can intelligent life thrive to the point where we can achieve interstellar travel?
The real question isn't "how badass were stone age humans", it's "can the smartphone generation re-invent stone age technology quickly enough to survive"?
https://www.outsideonline.com/2411125/lynx-vilden-stone-age-...
There are certainly some ecosystems such as fishing communities north of Vancouver that would do well and be shielded from any nuclear exchange, but the wild deer population in Massachusetts would likely not be sufficient for any significant number of modern stone age men to survive.
As for the great filter, I've always thought that the real danger is something that would cause say, one person, to have an outsized destructive power. Imagine if we successfully invent nanobots that can self-replicate, for example, and anyone with the right set of skills could program them. In that scenario, it's within the capability of any individual to create a deadly disease. You just need one unhinged person to trigger a horrible disaster. Nanotech could be much more dangerous than nukes, and if you combine strong AI and nanotech, I could see that being an immense survival risk.
- Dust - Supply chain - ~40% less watts/square meter
Of these the most unproven is the supply chain problem. The link below summarizes why solar doesn't work in the short-term for mars habitation missions - it's an open question as to whether there are economically extractable deposits of silicon, cadmium, and other materials to build out a solar farm. Bear in mind, terrestrial resource extraction makes extensive use of water.
https://medium.com/swlh/solar-power-is-never-going-to-work-o...
As for dust, the Mars rovers have shown it's not a real issue, wind removes most of it, and if we actually have people there, we can occasionally clean the arrays too.
Would I rather bring a nuclear reactor to Mars? Sure, but I also think we can make it work with just solar if we have to.
I used to believe this, until the pandemic. Now I think bio weapons are infinitely more dangerous than nukes. Imagine if COVID was a few times more contagious and as deadly as it's close relatives SARS and MERS. Not a big stretch really.
We would be pondering extinction right now. If the power was still working.
The current pandemic revealed how fragile our supply chains are, and I still consider it a small miracle that the impact so far was so small. Lots of people are in dire straits, yes, but the world structurally didn't change much.
A pathogen could kill fast, in which case some islands would be warned in time to close borders and survive.
Or a pathogen could have a long incubation, in which case it is surely going to be somewhat survivable by some percentage of the population
Making it spread through the atmosphere worldwide, while remaining virulent in sunshine for weeks, would be a hard problem to solve.
No, they won't. Even if we restrict to just fission power, on a thousand year time horizon we can expect thorium reactors and extraction of uranium from seawater, which multiplies the available energy by a factor of at least a thousand.
Furthermore, on that time horizon we can expect fusion to be available, and deuterium from seawater multiplies the available energy by a factor of about a billion.
Not to mention that on a thousand year time horizon, we should be making full use of the available solar energy in Earth's vicinity by means of orbital power stations, in which case we won't even need any other energy source on that time horizon except for specialized uses like fast spacecraft.
> On a thousand year time horizon it's entirely plausible that maintaining a purely renewable economy makes the production of certain materials impractically expensive
And it also makes it practically certain that any material that's that expensive to produce won't be needed anyway, since cheaper substitutes will be found.
"Limited resources" by itself simply doesn't strike me as a plausible Great Filter.
May soon reach? I doubt it. I'd say there's a significant filter between our technology level and large-scale inter-solar-system colonization. It's not at all clear that there is a strong motivation for that - except for a continuous-growth economy, which is kind of unsustainable anyway. Once the population stabilizes and human civilization is basically energy-neutral (i.e. not taking more than the sun provides), where's the great need to colonize someplace else (as opposed to communicating)? And if we don't stabilize - civilization will burn itself out soon enough, colonization or no.
> Even if life only evolves once per galaxy, that still leaves the problem of explaining the rest of the filter
No it doesn't. It's extremely unlikely that one planet with life will travel to a different galaxy. Even with intelligent life it's extremely unlikely. Only if instantaneous travel were possible would this be likely.