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Thread: What do you think is the most likely explanation for the Fermi paradox?

  1. #601
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    Article in Scientific American January 2020 pp 32-39.
    The Galactic Archipelago by Caleb Scharf.
    Concludes most likely resolution to FP is that galactic settlement occurs in waves and that our species has arisen on an out-of-the-way planet during a local lull in interstellar exploration.
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    What exactly constitutes a dyson swarm? A dozen 'habitats' orbiting a star? A hundred? A million? How large are they and what volume of them would be required to be detectable at certain distances?

    After a certain point it just seems like the perpetual logistical train of feeding each individual member of such a swarm with all of the various materials needed to maintain life would become untenable very quickly.

    No space-man is an island and neither is a space habitat. How much far-flung phosphorus and nitrogen is being hauling around for this spectacle and at what cost? Is it truly sustainable for any length of time?

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    Quote Originally Posted by deadie148 View Post
    What exactly constitutes a dyson swarm? A dozen 'habitats' orbiting a star? A hundred? A million? How large are they and what volume of them would be required to be detectable at certain distances?
    Far more then any of that, I believe the numbers can be in the trillions or even quadrillions (though this is going off of memory). Each habitat would be dozen of miles long and house 10's of thousands of people up to millions. These can be built using materials that exist today also, so no super strong future materials needed to construct them.

    To be detectable, you'd probably only need enough to block 0.1% of your stars light, since that is what our planet detecting telescopes are able to pick up.

    After a certain point it just seems like the perpetual logistical train of feeding each individual member of such a swarm with all of the various materials needed to maintain life would become untenable very quickly.
    Oh, these types of space habitats don't need to be resupplied. They are large enough to be self sustaining, all they would need is energy input from the sun. I agree completely that if the entire Dyson Swarm needs to be resupplied from Earth, that would be a nightmare! It could never work that way. The only way for a DS to function is to build not just space habitats, but self sustaining space habitats. If you aren't able to build space habitats that function completely on their own (think of a colony ship traveling between the stars) then a DS will never work.

    No space-man is an island and neither is a space habitat. How much far-flung phosphorus and nitrogen is being hauling around for this spectacle and at what cost? Is it truly sustainable for any length of time?
    When the space habitats are on the scale of miles, the habitat itself would have it's own ecosystem and be self sustaining. Also, to give you an idea of just how futuristic these types of things can get, one possible solution to running out of elements that we need a lot of is to just synthesis them from the sun. You can ring the sun with magnetic accelerators just like we have in a particle accelerator (it's in space, so already in a vacuum), and since it's around the sun it's being powered by the sun itself. You can just accelerate a huge amount of the suns plasma and smash it together in a massive particle accelerator and create any element that you want, essentially for free. Both the energy and the materials for it are provided by the sun, so again it's just a matter of engineering the infrastructure to take advantage of this.

    But that is pretty far down the line for a Dyson Swarm, by the time you start running out of any elements you have already built a good chunk of your swarm.

  4. #604
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    Basically, they ain't there.

    https://arxiv.org/abs/1912.08386

    Why SETI Will Fail
    B. Zuckerman
    (Submitted on 18 Dec 2019)

    The union of space telescopes and interstellar spaceships guarantees that if extraterrestrial civilizations were common, someone would have come here long ago.

    SHORT PAPER: https://arxiv.org/pdf/1912.08386.pdf

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    Quote Originally Posted by deadie148 View Post
    After a certain point it just seems like the perpetual logistical train of feeding each individual member of such a swarm with all of the various materials needed to maintain life would become untenable very quickly.

    No space-man is an island and neither is a space habitat. How much far-flung phosphorus and nitrogen is being hauling around for this spectacle and at what cost? Is it truly sustainable for any length of time?
    Quote Originally Posted by Dave241 View Post
    Oh, these types of space habitats don't need to be resupplied. They are large enough to be self sustaining, all they would need is energy input from the sun. I agree completely that if the entire Dyson Swarm needs to be resupplied from Earth, that would be a nightmare! It could never work that way. The only way for a DS to function is to build not just space habitats, but self sustaining space habitats. If you aren't able to build space habitats that function completely on their own (think of a colony ship traveling between the stars) then a DS will never work.



    When the space habitats are on the scale of miles, the habitat itself would have it's own ecosystem and be self sustaining.

    Self sustaining, but material losses will still occur.

    A perpetual logistical train would exist, but largely robotic self maintaining replicative Von Neumann machines. Which is merely an extension of the kind of automated manufacturing capacity you'd need to build and constantly maintain that many space stations and satellites anyway.
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    I've kept out of this discussion because there isn't a whole lot of concrete data to work with. I do disagree with a few assumptions that seem to be prevalent in this thread though.

    The first is that intelligent life will naturally expand it's presence and inhabit ever increasing areas.

    I don't see this being true. We, as a species, are rather limited in where we want to live. It's true we can be found across the planet but we didn't consciously decide to move there. If the early humans who left Africa knew they would end up in Barrow Alaska they would have turned around and headed back south. Circumstances led them to move outward in search of food. They didn't move into those areas because they wanted to, they moved because, at the time, they had to do so to survive.

    People move to less desirable areas because of economic necessities, not because they like the area. Often, when the economic reasons go away, they head back to better areas for living. There are a lot of ghost towns out there, they were popular for a time because of local resources but when the resources dried up so did the people.

    I don't see a lot of retirees moving to the Sahara or Antarctica. Once their income stabilizes without the need for a job they are more likely to move to Florida or another such comfy climate.

    Although there are resources off planet that we will likely exploit most of them can be more easily found among the asteroids and moons than on planetary surfaces. There's not a lot driving us to colonize other planets other than desire. Desire, however, can be fleeting and is not shared by all. Once again, when the resources dry up so will our presence.

    So I don't think it's a given that intelligent life will colonize other planets unless that planet is already a comfy place to live. Perhaps such places exist out there but right now we don't know of any and if they exist they will be hard to get to.

    Space habitats may be able to manufactured that provide all the comforts of a planet but what's going to pay the bills? Micro gravity manufacturing will cover some of it but that will only get you so far. Off-sea drilling and mining exists but I don't see cities rising out of the sea. The operators tend more towards long term contracts and when those contracts expire it's back to where they actually want to be.

    Another assumption is population growth.

    Although our population is currently increasing at an alarming rate that growth is mainly in under developed areas. Developed areas actually have problems with maintaining populations and sometimes have to encourage families to expand. I see this trend continuing and if we manage to bring up the economic level of all humans we will likely see world populations start decreasing again. Under developed areas are not likely to venture out to space.

    Once you remove excessive population growth from the equation the need for ever increasing numbers of space habitats goes away.

    There is also a problem with continual growth regarding political stability. Colonies tend to fracture from their homeland and that does not always happen peacefully. Imagine hundreds of thousands of individual habitats in space. How will competition affect their stability? Even today we are seeing a rejection of world government, everybody wants to set their own rules. How will that work across thousands of colonies?

    A final problem I see is genetic stability. If we have hundreds of thousands of individual habitats across the habitable zone and beyond then we will start to see genetic drift. Expand that to include exoplanets around other stars and eventually we won't be one species anymore but many.

    People and their governments will likely want to limit any such expansion to avoid the issues associated with it. Who needs a renegade colony to deal with?

    If population growth does stabilize and off planet colonies are limited then our energy requirements will not increase as some predict. If we do harvest the entire energy output of the Sun if will be because we need it for some future technology, not to drive our population growth. Such energy levels may be necessary for some future tech such as wormhole generation or other things we can't currently imagine.

    I've never been a fan of the Kardashev scale for civilizations. I think it's hogwash. Perhaps the most advanced civilization out here has rather modest energy requirements producing only what they need for their modest, but sustainable population.

    If we do find a Dyson sphere out there I doubt it's inhabitants will be pure biologicals anymore. Dyson spheres make sense for a distributed intelligence.

    Some future techs may change the equation. FTL for example although I tend to consider that fantasy. Non FTL teleportation is another one that I see as more probable but may well require huge energy outputs. More probable in this context means it's above fantasy, but not by much.

    Von Neumann machines could change the equation considerable, they could enable the automatic generation of "comfy" habitats. They would not, however, solve many of the other issues regarding political and genetic stability. Such technology is a double edged sword and we may find it best to limit it's use.

    We tend to see the future as a reflection of what we are today. We live in a growth dominated society right now but it was not always so. Perhaps in the future growth will be replaced with stability and sustainability.

    We may ultimately end colonizing other areas of the Solar System, but I don't see it as a never ending growth. Tourism may be the biggest driving force.

    I'm not really interested in long term discussions on this topic. We simply don't have enough hard data to drive such discussion. I did want to put my two cents into the discussion though. It's my (current) opinion. Others have different opinions and that is OK. Time will tell but I won't be here to know who was right in the end.

    Just some Sunday morning rambling...

  7. #607
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    I think the problem of the Fermi paradox is "Why haven't we been contacted by a Von Neumann probe that is also a Bracewell Probe?" A VNP would need an AI with the IQ of a bacterium, which we should be able to do. And everything we have sent out of the solar System has been a (very primitive) Bracewell Probe...Pioneer Plaque, Voyager Record, Far Horizon Message.
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    Quote Originally Posted by Bearded One View Post
    I do disagree with a few assumptions that seem to be prevalent in this thread though.

    The first is that intelligent life will naturally expand it's presence and inhabit ever increasing areas.

    I don't see this being true.
    Why would you disagree with this? In every instance in history, whenever life (intelligent or not) has had both the opportunity and the ability to expand it's habitat, it has done so. I honestly can't think of any counterexamples either. I think it's a safe assumption to make that this will continue to hold true going forward in the vast majority of cases.

    We, as a species, are rather limited in where we want to live. It's true we can be found across the planet but we didn't consciously decide to move there. If the early humans who left Africa knew they would end up in Barrow Alaska they would have turned around and headed back south. Circumstances led them to move outward in search of food. They didn't move into those areas because they wanted to, they moved because, at the time, they had to do so to survive.

    People move to less desirable areas because of economic necessities, not because they like the area. Often, when the economic reasons go away, they head back to better areas for living. There are a lot of ghost towns out there, they were popular for a time because of local resources but when the resources dried up so did the people.
    This kind of goes against your point about populations not expanding. You brought up that we humans are not able to easily survive in Barrow Alaska, so much so that our ancestors would have turned and fled at the idea, and yet today here we are living there anyway. And as far as ghost towns, they are an exceedingly small % of the inhabited towns, so I don't see that as being a big factor.

    Although there are resources off planet that we will likely exploit most of them can be more easily found among the asteroids and moons than on planetary surfaces. There's not a lot driving us to colonize other planets other than desire. Desire, however, can be fleeting and is not shared by all. Once again, when the resources dry up so will our presence.
    For a Dyson Swarm, the main resource that is collected is energy from the sun, and that isn't going to dry up at all. Material resources that are collected in space would mostly be used for other constructions that are also in space. Again, you have to imagine the pieces of a Dyson Swarm as self contained vessel similar to a colony ship on a 1,000 year long voyage to another star.

    Space habitats may be able to manufactured that provide all the comforts of a planet but what's going to pay the bills?
    I dunno. What currently "pays the bills" for Puerto Rico, or for New Zealand? The best answer is probably the citizens living there, right?

    Micro gravity manufacturing will cover some of it but that will only get you so far. Off-sea drilling and mining exists but I don't see cities rising out of the sea. The operators tend more towards long term contracts and when those contracts expire it's back to where they actually want to be.
    You don't? Both China and Japan have built artificial islands in the ocean. Also, with off sea drilling you can still get back to land relatively quickly, and the goal isn't to live there permanently anyway. I will ask you do you think that permanent space habitats are impossible to build? Because it kinda sounds like you do, and I will agree that if it's impossible to have a permanent habitat in space then it's also impossible to build a Dyson Swarm.

    .............
    The rest of your post I'm going to address in one chunk, and I'm going to do so by asking you this: If permanent space habitats are possible, then how long do you think it's possible for a civilization to go without ever building one? In other words, in 10,000 years do you really think that humans will still remain only on Earth? You don't think that we'd even bother to build a single self sustaining space habitat in the next 10,000 years? What about the next 100,000 years? We'd really go 100,000 years without a single nation ever bothering to try it? What about a million years? 10 million? That's an awfully long time for stagnant growth.

    I hope you see were I'm going in that eventually, someone is going to build one. So, now you have one built, and this is a space habitat that you can think of as a small nation in itself. It's self sustaining, has it's own industry, is able to manufacture it's own goods and engage in trade with other nations (or other space habitats). It probably has upwards of 10,000 people living in it. Also, because it has it's own manufacturing and that manufacturing is probably focused on making things to replace parts of it's own structure, it would also have the ability to make every piece needed for another space habitat. In other words, it can expand without any input from Earth.

    So you now have a stable space population that is capable of it's own growth. So that 1 habitat can now become 2. Which can become 4, ect.

    So, rather then asking how is it possible to build one, I am instead very curious in this question: How can you NOT build one? Give a species the ability to construct self sustaining space habitats and millions of years of time, and a Dyson Swarm is pretty much inevitable. So is it that you think we can't build these space habitats, or is it that you don't think we will last 1 million years?

    Also, heres a few other things you mentioned:

    Colonies tend to fracture from their homeland and that does not always happen peacefully.
    Indeed. And when the homeland tries to stop the colonies from fracturing, that usually fails and they fracture away anyway. This is something that I see as encouraging a Dyson Swarm, not a barrier to it. As the habitats fracture that is an incentive to build more habitats and expand the Dyson Swarm. To put it another way: Lets say it's 100,000 years in the future, manufacturing space habitats has become trivially easy, and you and your group don't like the current government and want to leave. Why wouldn't you? The current government isn't going to be able to stop everyone who tries to leave, so this will happen regardless.

    A final problem I see is genetic stability. If we have hundreds of thousands of individual habitats across the habitable zone and beyond then we will start to see genetic drift. Expand that to include exoplanets around other stars and eventually we won't be one species anymore but many.
    YUP! I agree with this 100%, and I would assume that on the time scales of galactic colonization, this is inevitable rather then just a possibility.

    People and their governments will likely want to limit any such expansion to avoid the issues associated with it.
    But they won't be 100% successful. They can't be. So some will end up leaving anyway, and since those that do leave in this senario will have self sustaining space habitats they can just go into some other orbit around the sun and quietly live out there, all the while expanding even if the planet doesn't. 1 million years later the part that broke away has now built you your Dyson Swarm.

    Perhaps the most advanced civilization out here has rather modest energy requirements producing only what they need for their modest, but sustainable population.
    And if this was true for the entire universe, that would certainly solve the Fermi Paradox. But what about the portion of space faring civilizations that don't remain modest, and instead decide that they do want to expand? For that matter, what do you do about the portion of your OWN population that doesn't want to remain modest and instead wants to expand? Do you threaten to kill anyone who disagrees with you?

    If we do find a Dyson sphere out there I doubt it's inhabitants will be pure biologicals anymore.
    I agree with this as well.

    I'm not really interested in long term discussions on this topic.
    Unfortunately, when talking about the Fermi Paradox you have to talk long term because the entire point is why don't we see any 100 million year old civilizations. You can't address that without also thinking on time scales of 100 million years.

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    Dave241 "why don't we see any 100 million year old civilizations. You can't address that without also thinking on time scales of 100 million years"

    I think this is probably the crux of the Fermi paradox. - Why don't we see 100 million year old civilisations? 1

    100 million years in cosmic terms is tiny, but, one would expect a technological civilisation to have developed enough within this time to have spread across their galaxy. Is it too presumptuous to expect humans, assuming they survive for 100 million years, to have at least started to colonised local solar systems within the Milkyway, and probed the majority of it after this time period? Then you look at other species on this planet alone that survived for much longer than 100 million years yet never evolved into technological intelligent civilisations. One of the questions is why not?

    There are far too many assumptions we have to accept to make any definitive conclusion to the Fermi paradox.
    When you delve into it there are countless factors that were necessary for us (the only technological life we have has an example to use) to exist! This makes the odds of us ever existing lower than the number of observable stars in the universe. Don't quote me but IIRC someone estimated the odds being in the region of 1 in 10^27 chance of humans ever existing. So if you choose to take these odds literally, assuming there are more stars than we can observe (which is highly likely), the odds show us that there will be around 1 technological civilisation for every 10^27 stars. This would then indicate that we (humans), are the only intelligent technological species within our observable universe.

    We only have one example of the existence of technological species to work with!
    I don't think there is a right or wrong view point, so long as the idea fits within mainstream science laws. All things should be considered plausible (within this frame) no matter how wild or speculative they seem.


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    Quote Originally Posted by Dave241 View Post
    Unfortunately, when talking about the Fermi Paradox you have to talk long term because the entire point is why don't we see any 100 million year old civilizations. You can't address that without also thinking on time scales of 100 million years.
    What is a 100 million year old civilization? We can talk about hundreds of years old human civilizations, albeit with heavy changes during that time, but we have no perspective on what would be meant by an entity lasting a hundred million years. Heck, we get heavily into speculation just talking about what human civilization might be like a couple centuries from now, but with those timescales we would get so far into the weeds debating different speculations I don’t see what useful discussion can be had.

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    A 100 million year old civilization will probably be a lot like a 100 thousand year old civilization. There will be nothing unknown left to discover.

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    Quote Originally Posted by Bearded One View Post
    I've kept out of this discussion because there isn't a whole lot of concrete data to work with. I do disagree with a few assumptions that seem to be prevalent in this thread though.
    Very true there is little concrete data to work with. That is why we have to use the best logic possible.

    I think you, and some others, are forgetting about the Principle of Mediocrity.

    That would say there is nothing unique, or even particularly uncommon, in the way that humans behave and see the world. Within the set of technological species, we shouldn't be far from typical.

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    Quote Originally Posted by Chuck View Post
    A 100 million year old civilization will probably be a lot like a 100 thousand year old civilization. There will be nothing unknown left to discover.
    Or, perhaps every intelligent species finds out the true nature of the universe at some point. Like The Matrix or something.

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    Evidence for alien life is right in front of us, but we can't see it because we don't recognize it for what it is.

    https://phys.org/news/2020-01-alien-life-theories.html
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    Quote Originally Posted by Roger E. Moore View Post
    Evidence for alien life is right in front of us, but we can't see it because we don't recognize it for what it is.
    .. which is not what this article has to say, at all ...

    One question of interest it does pose is:
    When it comes to alien life, is it enough for scientists to assume "we'll know it when we see it"?
    So, if we're really exploring using the scientific process, then there is no need for any 'assumptions' of: 'knowing it when we see it'.
    The scientific method does not work by first assuming something.

    Even, for some reason, we were not to notice something, it wouldn't matter because there is no need to assume there's something there to be missed in the first place .. (because that too would be starting the process with an initial assumption).

    Assumptions (or posits) is what logic starts with, and logic is not science.

    This whole question emphasises the error being made when we specifically go on a hunt looking for a pattern-match (the 'keys under the streetlight' scenario).
    There is no imperative I know of that: 'we must find life elsewhere' .. if there is, then we have already departed science, and are already undertaking a hunt for the Holy Grail, (which is usually accompanied by all of its well-known unproductive consequences).
    This point is yet another of my explanations for the non-paradox, commonly referred to as 'the Fermi paradox'.

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    Quote Originally Posted by kzb View Post
    Very true there is little concrete data to work with. That is why we have to use the best logic possible.

    I think you, and some others, are forgetting about the Principle of Mediocrity.

    That would say there is nothing unique, or even particularly uncommon, in the way that humans behave and see the world. Within the set of technological species, we shouldn't be far from typical.
    Assuming I grant that, then I could reasonably say that other species like us would be virtually undetectable by us since we, in turn, would be undetectable by another civilization with our technology unless they caught one of our rare attempts at interstellar communication.

    Generally, I see a lot of arguments put forth that arenít just speculations on what could be possible based on known physics, but rather a list of assumptions and insistence that the assumptions must be true. Immortal, easily observable, maximally expansionist interstellar civilizations, for instance, are often claimed to be inevitable if there are any intelligent species at all, and lack of immediate evidence for such is claimed to be strong evidence for no other intelligent species to exist. I donít accept such arguments, rather it typically looks like an outgrowth of hopes and dreams that the arguer has regarding humanityís distant future.

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    Quote Originally Posted by Van Rijn View Post
    Assuming I grant that, then I could reasonably say that other species like us would be virtually undetectable by us since we, in turn, would be undetectable by another civilization with our technology unless they caught one of our rare attempts at interstellar communication.

    Generally, I see a lot of arguments put forth that arenít just speculations on what could be possible based on known physics, but rather a list of assumptions and insistence that the assumptions must be true. Immortal, easily observable, maximally expansionist interstellar civilizations, for instance, are often claimed to be inevitable if there are any intelligent species at all, and lack of immediate evidence for such is claimed to be strong evidence for no other intelligent species to exist. I donít accept such arguments, rather it typically looks like an outgrowth of hopes and dreams that the arguer has regarding humanityís distant future.
    Being kind here; the notion of the universality of known physics is, itself, typically attributed to Occam's Razor, which in turn, may also then be the implied basis for arguing some speculation over another here, I think(?)

    The common mischaracterisation of Occam's however, (ie: 'the simplest theory (or assumption) is most likely the right one'), then leads to the outright misconception that science, somehow, then has the right to make a claim on: 'what is most likely right', rather than: 'what would most likely agree with observations'. (Once 'what is right' enters into a discussion, it doesn't take much to assert that 'assumptions' must therefore 'be true', under the same misconception).

    Without the mischaracterisation however, Occam's would be: 'the simplest theory (or assumption), that agrees with data is the best path to understanding', so then that theory/assumption is clearly the best theory/assumption. This is completely different to believing the Razor leads to 'how things, most likely, would eventually work', (including remote, hypothetical civilisations), as if the universe (and civilisation) is a simulation made by some dodgy programmer who therefore, for some reason, has to keep it simple.

    I guess what I'm saying here is that once one introduces 'what could be possible based on known physics', which itself is an outcome of the application of Occam's, one then also, (under its appropriate interpretation), has to then consider the simplicity of competing assumptions?

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    Quote Originally Posted by Van Rijn View Post
    What is a 100 million year old civilization? We can talk about hundreds of years old human civilizations, albeit with heavy changes during that time, but we have no perspective on what would be meant by an entity lasting a hundred million years. Heck, we get heavily into speculation just talking about what human civilization might be like a couple centuries from now, but with those timescales we would get so far into the weeds debating different speculations I donít see what useful discussion can be had.
    Its no beyond the realm that such a civilisation can exist. We have example of species of animals here on earth that have not evolved much over similar periods of time - crocodiles for example. Though granted, they have not evolved to be technologically adept, which might/could influence the future evolution of a species.

    But I do strongly agree with your next post -

    "Generally, I see a lot of arguments put forth that arenít just speculations on what could be possible based on known physics, but rather a list of assumptions and insistence that the assumptions must be true. Immortal, easily observable, maximally expansionist interstellar civilizations, for instance, are often claimed to be inevitable if there are any intelligent species at all, and lack of immediate evidence for such is claimed to be strong evidence for no other intelligent species to exist. I donít accept such arguments, rather it typically looks like an outgrowth of hopes and dreams that the arguer has regarding humanityís distant future"

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    Quote Originally Posted by Van Rijn View Post
    Assuming I grant that, then I could reasonably say that other species like us would be virtually undetectable by us since we, in turn, would be undetectable by another civilization with our technology unless they caught one of our rare attempts at interstellar communication.

    Generally, I see a lot of arguments put forth that aren’t just speculations on what could be possible based on known physics, but rather a list of assumptions and insistence that the assumptions must be true. Immortal, easily observable, maximally expansionist interstellar civilizations, for instance, are often claimed to be inevitable if there are any intelligent species at all, and lack of immediate evidence for such is claimed to be strong evidence for no other intelligent species to exist. I don’t accept such arguments, rather it typically looks like an outgrowth of hopes and dreams that the arguer has regarding humanity’s distant future.
    Fair enough, but this is the so-called "Bleak Future" family of explanations.

    What this means is that every single intelligent species ever evolved in the galaxy has either got destroyed or failed to advance beyond its home system (even though many have had billions of years to do so).

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    It's not outside the realm of plausibility that a hypothetical community of intelligent, technological lifeforms (not going near the keyword civilization) could spread their life to a few other systems, not find it worth repeating, and then stop or drastically slow. Maybe they sent VN probes around the Galaxy a few million or billion years ago to see what was there, but learned from experience that going there in person and setting up shop was not worth the candle, that the benefits they saw did not perhaps outweigh the massive costs. So we'd end up with small scattered clumps of inhabited systems, but little or no further growth.

    Another idea is that, having achieved interstellar travel and population control, hypothetical travelers could see no benefit to colonizing at all. Even if they are curious enough to go in person, it's conceivable that they would be just living on their own vessels and occasionally stopping at stars to restock, refuel and repair. To a being who grew up on a starship, the point of planets would be easy to miss.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Quote Originally Posted by Noclevername View Post
    It's not outside the realm of plausibility that a hypothetical community of intelligent, technological lifeforms (not going near the keyword civilization) could spread their life to a few other systems, not find it worth repeating, and then stop or drastically slow. Maybe they sent VN probes around the Galaxy a few million or billion years ago to see what was there, but learned from experience that going there in person and setting up shop was not worth the candle, that the benefits they saw did not perhaps outweigh the massive costs. So we'd end up with small scattered clumps of inhabited systems, but little or no further growth.

    Another idea is that, having achieved interstellar travel and population control, hypothetical travelers could see no benefit to colonizing at all. Even if they are curious enough to go in person, it's conceivable that they would be just living on their own vessels and occasionally stopping at stars to restock, refuel and repair. To a being who grew up on a starship, the point of planets would be easy to miss.
    People always assume that ET will be some totally controlled machine that acts with single logical purpose. When on Principle of Mediocrity considerations they are more likely to behave similar to humans.

    Yes this or that "might" happen, or "it's conceivable" but of course almost anything "might" or "conceivably" be the explanation. So it doesn't get us anywhere. There are any number of "another idea is..." explanations. Their problem is they have to apply universally to each and every intelligent race evolved in the galaxy over billions of years.

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    Quote Originally Posted by kzb View Post
    Fair enough, but this is the so-called "Bleak Future" family of explanations.

    What this means is that every single intelligent species ever evolved in the galaxy has either got destroyed or failed to advance beyond its home system (even though many have had billions of years to do so).
    And there are some of those assumptions. I see no reason to assume we could detect any species that went beyond its solar system. But also, I see no reason to reject possibilities just because one doesnít like them on an emotional level. Mind you, I can imagine a number of possibilities that I would not consider bleak that involve star fairing species. On the other hand, I see nothing emotionally satisfying about a maximally expansionist civilization converting galaxies into more of itself.

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    Quote Originally Posted by kzb View Post
    People always assume that ET will be some totally controlled machine that acts with single logical purpose. When on Principle of Mediocrity considerations they are more likely to behave similar to humans.

    Yes this or that "might" happen, or "it's conceivable" but of course almost anything "might" or "conceivably" be the explanation. So it doesn't get us anywhere. There are any number of "another idea is..." explanations. Their problem is they have to apply universally to each and every intelligent race evolved in the galaxy over billions of years.
    How many is that? We know of one, and we haven't done any of it yet.

    No one explanation has to cover ALL the available possibilities for why we haven't seen anything. Distance is already an explanation. Time is already an explanation. Technical challenge is already an explanation. Energy expenditure is already an explanation. The conditions required to give rise to complex intelligent technological civilizations in the first place, which increasingly appear to be rare, are probably enough of an explanation.

    Success should not the default expectation of colonizing a whole Galaxy. Failure is. Defying that is not something we can look at and say "Why aren't they here?" The real question is, "How could we possibly be thinking they'd come here?"
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Quote Originally Posted by Noclevername View Post
    How many is that? We know of one, and we haven't done any of it yet.

    No one explanation has to cover ALL the available possibilities for why we haven't seen anything. Distance is already an explanation. Time is already an explanation. Technical challenge is already an explanation. Energy expenditure is already an explanation. The conditions required to give rise to complex intelligent technological civilizations in the first place, which increasingly appear to be rare, are probably enough of an explanation.

    Success should not the default expectation of colonizing a whole Galaxy. Failure is. Defying that is not something we can look at and say "Why aren't they here?" The real question is, "How could we possibly be thinking they'd come here?"
    I could accept "time" as the explanation if someone could come up with a viable reason why the galaxy has only recently evolved intelligent life.

    Current reasoning is that there could have been Earth-like planets 4 billion years before Earth itself existed, with the peak frequency of intelligent life appearance about a billion years ago.

    If there is a good reason this picture is actually incorrect, then I could go with time as the explanation.

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    Quote Originally Posted by kzb View Post
    I could accept "time" as the explanation if someone could come up with a viable reason why the galaxy has only recently evolved intelligent life.

    Current reasoning is that there could have been Earth-like planets 4 billion years before Earth itself existed, with the peak frequency of intelligent life appearance about a billion years ago.

    If there is a good reason this picture is actually incorrect, then I could go with time as the explanation.
    Well a very simple and possible explanation would be - The universe is still very much in its infancy, therefore intelligent life could be very much in its infancy. So, for example, if the odds of intelligent life evolving is very low then the time required for it to happen is likely to be be very long.

    There is also the relationship between the vast distances and time. So another explanation could be about simultaneity, in that, rather than only considering the length of time for intelligent life to develop (which we have only one example of) but also considering if/when intelligent life develops at a similar period of time in relationship to the age of the universe. In other words co-existence within the same reference frame. Don't forget when we look out into the stars we are observing the past. Any intelligent species looking out for a signal from us, say beyond 150 lights years away, would detect nothing.

    If we take a look at life here on Earth as an example; If we had no fossil evidence of the dinosaurs would we ever have known they existed at all? They went extinct around 65 million years ago, a snip-it relative to the age of the universe even now, let alone its potential age.
    Last edited by cosmocrazy; 2020-Jan-08 at 01:06 PM.

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    Quote Originally Posted by kzb View Post
    I could accept "time" as the explanation if someone could come up with a viable reason why the galaxy has only recently evolved intelligent life.

    Current reasoning is that there could have been Earth-like planets 4 billion years before Earth itself existed, with the peak frequency of intelligent life appearance about a billion years ago.

    If there is a good reason this picture is actually incorrect, then I could go with time as the explanation.
    OK, say you're right. Intelligent life existed long ago, for the sake of this argument. That still leaves ALL the other obstacles I listed. Any ONE of which equals a no-show.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Maybe we are the first.
    SOMEONE must be first.
    SHARKS (crossed out) MONGEESE (sic) WITH FRICKIN' LASER BEAMS ATTACHED TO THEIR HEADS

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    Quote Originally Posted by Noclevername View Post
    OK, say you're right. Intelligent life existed long ago, for the sake of this argument. That still leaves ALL the other obstacles I listed. Any ONE of which equals a no-show.
    I agree and just maybe, even if there are countless advanced species of life out there, how do we know if its even possible that all the obstacles can be overcome?

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    Quote Originally Posted by Tom Mazanec View Post
    Maybe we are the first.
    SOMEONE must be first.
    This was partly my point when I mentioned the infancy of the universe. If say for example, on average the universe develops 1 technological intelligence once every 13 billion years then we could well be the first.

    Alternative to that is to look at it another way. Say on average each galaxy only ever develops 1 technological intelligence. This could mean that there are / have been or could be hundreds of billions of technological intelligence throughout the universe and time. But due to the vast distances and time scales involved, it/ they are and will possibly remain isolated from each other.

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    Quote Originally Posted by Tom Mazanec View Post
    Maybe we are the first.
    SOMEONE must be first.
    OK, but tell us WHY?

    Theories say that there were Earth-like planets 8 billion years ago.

    Theories also say that all the steps from the beginning of life to humans were almost inevitable.

    So if we are the first, what is wrong with these theories? This is what we have to explain.

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