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There seems to be a giant mismatch about what side is open minded. People who think its most likely aliens think it’s closed minded to assign that low probabili

There seems to be a giant mismatch about what side is open minded. People who think its most likely aliens think it’s closed minded to assign that low probability, presumably because we’re this tiny corner of the universe. People who think it’s most likely not aliens Think it’s closed minded to assign everything else low probability, presumably because aliens are a tiny corner of everything else. Is it a misapplication of the anthropic principle to say there are probably gazillions of advanced aliens, given that we appeared and therefore life probably is common? Or is it a misapplication to say it’s probably just another of the gazillions of non-alien things we’ve seen? It’s all differences of opinion over which claim is the extraordinary one. It is bold to claim confidence about the impossibility of FTL travel, or bold to claim confidence about the possibility of it? Is it bold to say we’re a freak occurrence or bold to say we aren’t? Most generally, is it bold to say we know a lot or bold to say we don’t?

gfxgirl 6y ago
I thought the idea that there are gazillions of advanced aliens has been pretty much disproven by the fermi paradox. If there are gazillion, at least one out of all the diversity out there should have already colonized the entire galaxy and evidence should be plentiful.
- PoachedSausage 6y ago
  Maybe there has been some sort of accident of scale, like the intergalactic fleet in Hitch Hiker Guide to the Galaxy that arrives to destroy Earth but is eaten by a dog. There could be a banging ET party going at the Planck scale and we would never know, they might as well be on the other side of the universe.
  - godelski 6y ago
    The problem with this is that mechanics is not scale invariant. This puts bounds on creatures. Unless there's some crazy different way to compute I wouldn't expect a being to be able to have strong cognitive functions and be the size of a fly. They would also have a difficult time building advanced machinery to get to galactic travel scales. Similarly I wouldn't expect a creature the size of a Brontosaurus to become space faring. Because of their sizes they would have to consume significantly more resources to build simple things. A two story house probably couldn't be created out of wood or other basic biological materials making it difficult to transition into even the stone age. They also require higher food because energy requirements aren't linear. But think how much it costs to send a pound to space. Their first to space would be significantly more expensive. This doesn't mean these things are impossible because maybe there are ways around them, but it certainty shifts the probabilities by quite a bit. Given our current understanding of biology and mechanics it makes it much more probable for creatures to be within the ballpark of our size (let's say crow to elephant?).
    - PaulDavisThe1st 6y ago
      I think this is a mistaken way of thinking in general, because you're omitting time. Your assuming that intelligent/thinking/conscious creatures would necessarily function on timelines that make sense to us. If that were true, then what you're saying makes sense - there are real bounds on how fast you can move chemical energy from A to B, for example. But I see nothing preventing intelligent life from operating on massively longer timescales. This requires, of course, that you believe that intelligence (and maybe consciousness too) is substrate and timescale independent, which may or may not be a big ask depending on where you stand on these issues.
      - godelski 6y ago
        I think this is strange thinking because it breaks our laws of physics. The clock ticks at the same rate in internal reference frames, it is only different when looking at two different frames. But if you're talking about them acting at slower speeds or faster, then that brings along other problems similar to the mechanics ones we discussed (assuming we're not counting that they are in a slower reference frame). It really shifts the probabilities around. Even trees act relatively quickly because forces act fast. You'd have to be in a pretty extreme environment for other things to happen. As to chemistry, if they are moving faster then that means that they have more thermal energy. That comes with radiative problems (why humans stand) and this is much more difficult the smaller you are because you have less surface area. Which then puts large energy requirements on intake. And then the inverse is true. The thing is that aliens would still have to follow the laws of physics. There is no reason to expect that wouldn't be true and reasoning otherwise would take some pretty extraordinary evidence and probably win you several Nobel prizes.
        ChainOfFools 6y ago
        https://archive.org/details/OnBeingTheRightSize-J.B.S.Haldane https://archive.org/details/OnBeingTheRightSize-J.B.S.Haldan...
        godelski 6y ago
- mtts 6y ago
  According to the Chinese science fiction author Liu Cixin the Fermi paradox is solved by the certainty that if an alien civilization announces its presence to the rest of the universe, one of the gazillions of other advanced alien civilizations is sure to destroy it. So they keep quiet.
  - mensetmanusman 6y ago
    That would imply the laws of physics somehow dictate the self-manifestation or creation of intelligent clouds of elements (e.g. humans) who by their vary quantum waveform / nature are violent and want to destroy other clouds of elements even if the cost involves harvesting energy from your only local star.
    - emteycz 6y ago
      Not necessarily - the laws of physics might merely make it likely enough to be common.
  - yoz-y 6y ago
    The books and all are nice but the Dark Forest Theory doesn't hold agains much scrutiny. Among other reasons because if that were true we would be already dead. https://www.youtube.com/watch?v=zmCTmgavkrQ https://www.youtube.com/watch?v=zmCTmgavkrQ
    - galkk 6y ago
      I mean - it's called Dark Forest, but if you will look at any documentary, even dark forest is full of life. You will hear crickets, you will hear owls, you may see fireflies. The theory has catchy name, but even the earth's nature disproves it.
      - lambda_obrien 6y ago
        If you read the three books, you realize that the true message is that if you're considered a possible threat to an advanced species, they'll annihilate you, otherwise you'll be left alone. Maybe every other species which knows about us knows we can't even leave our own planet/moon right now, the most we can do is send useless robots to other planets over 30 years.
- 6gvONxR4sf7o 6y ago
  There’s a nice analysis of the Fermi paradox out there somewhere that takes into account uncertainties in each of the parameters. As you multiply them together, the uncertainties compound each other. The end result is a big old who knows, rather than a paradox. Our observations are compatible with a really wide variety of realities, many of which include lots of aliens and many of which don’t.
- shrimp_emoji 6y ago
  A possible chink is that civilizations just don't do that -- carpet colonize the whole galaxy, or fill it with their probes to the extent that we seem them all over the place. The Fermi paradox relies on material (probes, colonies) and light (signals). With the material explained away, the lack signals is much easier to explain in that we haven't listened long and we can only hear very loud signals. (Or maybe advanced civs don't use light and use gravity waves or tachyon beams or whatever, but you don't even need to go that far.) The only way we hear a signal is if it's: 1. loud (high energy) and aimed directly at us, like a tight beam 2. EXTREMELY LOUD and aimed everywhere, isotropically 1 is unlikely since they'd have to know where we are; 2 is unlikely since you're talking about an insane level of energy. If it's the case that civs don't seem to be making Dyson spheres or harvesting whole galaxies for energy, being able to throw around that kind of power is prohibitively expensive. In both these cases, the inverse square law applies (for every unit x of distance, the light's x² less bright). Ironically, that means we're more likely to detect signals from an improbably close civilization (like 4 light years next door, in Alpha Centuari), than from farther away -- and even then, by a chance sweep of an umodulated asteroid scanning beam[0] or something, if we happened to be paying attention at the time. 0: https://en.wikipedia.org/wiki/BLC1 https://en.wikipedia.org/wiki/BLC1
  - jrumbut 6y ago
    Do you know if about any simulations of what it would look like if there were alien radio operators? If there were 50 other Earths scattered around the galaxy (ones that have been broadcasting like us but for longer) should the first television have imnediately picked up interstellar "I Love Lucy" or would it be faint anomalies from SETI? Somewhere in between?
    - 7thaccount 6y ago
      The milky way is 100,000 light years across and I love Lucy is what, 60-70 years old? I would say we've reached a very small portion of the milky way
    - giantrobot 6y ago
      The inverse square law says no [0]. Even relatively high powered transmitters aren't detectable for an Arecibo-class antenna more than a few AU from Earth. If you want a signal detected light years away you need it to be highly directional. An isotropic radiator emitting enough power to be detected light years away is called a star. So any SETI signals we might detect would almost certainly need to be intentional. That doesn't mean they would need to be responses to something we've broadcast just the sender was aiming their transmitter towards the solar system and sent a signal. [0] https://web.archive.org/web/20140719094337/http://www.computing.edu.au/~bvk/astronomy/HET608/essay/ https://web.archive.org/web/20140719094337/http://www.comput...
- gfodor 6y ago
  Paradoxes are paradoxes precisely because they fail to disprove two contradictory claims. For the Fermi paradox, the paradox is that the immensity of the universe leading to life seems obvious, yet the complete absence of that life around us seems to show it's not there. So it disproves nothing, but actually highlights the difficulty of disproving either claim given the other.
  - sli 6y ago
    I never much liked this being called a paradox since it has so many built in assumptions, most of them centered around any given, theoretical alien civilization resembling a human civilization in any way. It's a limitation of what we know for sure, since there's certainly no rule that civilization elsewhere should resemble civilization on Earth. That's an acceptable limitation, it's difficult to notice things you don't know you should notice, but it's a limitation nonetheless. Of course, it's also possible for civilizations to be so far away that we will like never detect them due to the inverse square law. They could even be in parts of the universe we can't observe.
- stretchcat 6y ago
  Every advancing civilization will eventually create an internet. Once they do that, interstellar travel is off the table. Advanced civilizations stay closely packed because they cannot tolerate latency once they get a taste for near instant communication.
  - PaulDavisThe1st 6y ago
    Given that serious interstellar travel really requires FTL transport, I suspect that the two are rather closely connected.
    - willis936 6y ago
      Why is FTL necessary for interstellar travel? If you could go even 1% c then you could make journies that are multiple light years on the scale of centuries. It’s not until 50% c does time dilation start playing a significant role, but it would allow making a 10 l-yr journey in 17 years. Nature doesn’t care if we think there should be aliens or FTL travel. Nature doesn’t like casualty violated and that means we’re all going to be following its rules on the speed of causality. There are no cosmic-scale sentient forces that can shape space-time near us or else we would have noticed in observations decades ago.
    - stretchcat 6y ago
      I disagree, I think it probably would for humans.. but what about other advanced organisms? Maybe they have very long lives. Maybe their biology is more conducive to 'suspended animation' or some other form of hibernation. Maybe they've digitized their minds and can suspend execution of their thought processes for tens of thousands of years. Maybe their social traits (ant like hives perhaps?) make generation ships feasible while they would collapse into strive for humans.
    - _carbyau_ 6y ago
      So Competitive Quake/Counter Strike/ThingsKidsPlayTheseDays:-) will fund research into FTL transport for <1ms ping. Sadly, I could see it. Some billionaire somewhere wants "The Best" latency numbers and wants it on their yacht...
- bobsmooth 6y ago
  It really hasn't. [1] [1]https://arxiv.org/pdf/1806.02404.pdf https://arxiv.org/pdf/1806.02404.pdf
ncmncm 6y ago
Their best future course is to stop sniping at one another. It is possible that it's aliens. It is possible that it's not. We don't have enough evidence even to estimate probabilities, so anything further is pure speculation. Speculation is a look that wears no better on conservatives than on radicals. There is hardly a field to be found where young radicals are not promoting evidence for what the tenured consider anathema, waiting for the latter to retire or die and get the hell out of the way. As Max Planck said, "Science advances one funeral at a time." It is common to insist that the right idea wins in the end, but there is no reason to believe it: every case you can cite in its favor amounts to confirmation bias. The frequency of such examples that first languished for decades, with the original proposer driven from the field, would properly make us suspect that the majority of their also-correct peers remain unvindicated, however many false leads have been exposed. (Hypotheses promoted by women driven from a field make a rich vein of ideas to vindicate.) Loeb is right about one thing: the notion of "extraordinary evidence" is very destructive. Evidence is evidence. It is always easy to make greater demands on evidence you don't like than on evidence you do, and always easy find excuses to discount evidence incompatible with the consensus of the moment. Every field, to be considered legitimate, should maintain an officially taught compendium of "damned facts", evidence that seems to be incompatible with one or more leading theories. Even when a consensus theory is largely correct, the damned evidence will be the basis of any progress. Nature doesn't play favorites: it is possible for a consensus theory and all its challengers to be wrong. Evidence against one of the latter is not evidence in favor of the former.
- 6gvONxR4sf7o 6y ago
  > Loeb is right about one thing: the notion of "extraordinary evidence" is very destructive. Evidence is evidence. I agree with pretty much everything you're saying except this. Though I still do agree with this a bit. It seems like a shorthand for "be bayesian" that's unfortunately taken too far too frequently. But if I have a strong prior one way or another, I will need stronger evidence to turn me around. +1 on your main point though. Why can't more people be more comfortable in a state of uncertainty ;_;
  - ncmncm 6y ago
GlennS 6y ago
I think it's more that we know human nature, and we can see that people who believe we've been visited by aliens are engaging in story telling, not science. They're working back from the conclusion they want to be true, when they should instead start by weighing the evidence.

gfxgirl 6y ago

I thought the idea that there are gazillions of advanced aliens has been pretty much disproven by the fermi paradox. If there are gazillion, at least one out of all the diversity out there should have already colonized the entire galaxy and evidence should be plentiful.

PoachedSausage 6y ago
Maybe there has been some sort of accident of scale, like the intergalactic fleet in Hitch Hiker Guide to the Galaxy that arrives to destroy Earth but is eaten by a dog. There could be a banging ET party going at the Planck scale and we would never know, they might as well be on the other side of the universe.
- godelski 6y ago
  The problem with this is that mechanics is not scale invariant. This puts bounds on creatures. Unless there's some crazy different way to compute I wouldn't expect a being to be able to have strong cognitive functions and be the size of a fly. They would also have a difficult time building advanced machinery to get to galactic travel scales. Similarly I wouldn't expect a creature the size of a Brontosaurus to become space faring. Because of their sizes they would have to consume significantly more resources to build simple things. A two story house probably couldn't be created out of wood or other basic biological materials making it difficult to transition into even the stone age. They also require higher food because energy requirements aren't linear. But think how much it costs to send a pound to space. Their first to space would be significantly more expensive. This doesn't mean these things are impossible because maybe there are ways around them, but it certainty shifts the probabilities by quite a bit. Given our current understanding of biology and mechanics it makes it much more probable for creatures to be within the ballpark of our size (let's say crow to elephant?).
  - PaulDavisThe1st 6y ago
    I think this is a mistaken way of thinking in general, because you're omitting time. Your assuming that intelligent/thinking/conscious creatures would necessarily function on timelines that make sense to us. If that were true, then what you're saying makes sense - there are real bounds on how fast you can move chemical energy from A to B, for example. But I see nothing preventing intelligent life from operating on massively longer timescales. This requires, of course, that you believe that intelligence (and maybe consciousness too) is substrate and timescale independent, which may or may not be a big ask depending on where you stand on these issues.
    - godelski 6y ago
      I think this is strange thinking because it breaks our laws of physics. The clock ticks at the same rate in internal reference frames, it is only different when looking at two different frames. But if you're talking about them acting at slower speeds or faster, then that brings along other problems similar to the mechanics ones we discussed (assuming we're not counting that they are in a slower reference frame). It really shifts the probabilities around. Even trees act relatively quickly because forces act fast. You'd have to be in a pretty extreme environment for other things to happen. As to chemistry, if they are moving faster then that means that they have more thermal energy. That comes with radiative problems (why humans stand) and this is much more difficult the smaller you are because you have less surface area. Which then puts large energy requirements on intake. And then the inverse is true. The thing is that aliens would still have to follow the laws of physics. There is no reason to expect that wouldn't be true and reasoning otherwise would take some pretty extraordinary evidence and probably win you several Nobel prizes.
      - ChainOfFools 6y ago
        https://archive.org/details/OnBeingTheRightSize-J.B.S.Haldane https://archive.org/details/OnBeingTheRightSize-J.B.S.Haldan...
        godelski 6y ago
mtts 6y ago
According to the Chinese science fiction author Liu Cixin the Fermi paradox is solved by the certainty that if an alien civilization announces its presence to the rest of the universe, one of the gazillions of other advanced alien civilizations is sure to destroy it. So they keep quiet.
- mensetmanusman 6y ago
  That would imply the laws of physics somehow dictate the self-manifestation or creation of intelligent clouds of elements (e.g. humans) who by their vary quantum waveform / nature are violent and want to destroy other clouds of elements even if the cost involves harvesting energy from your only local star.
  - emteycz 6y ago
    Not necessarily - the laws of physics might merely make it likely enough to be common.
- yoz-y 6y ago
  The books and all are nice but the Dark Forest Theory doesn't hold agains much scrutiny. Among other reasons because if that were true we would be already dead. https://www.youtube.com/watch?v=zmCTmgavkrQ https://www.youtube.com/watch?v=zmCTmgavkrQ
  - galkk 6y ago
    I mean - it's called Dark Forest, but if you will look at any documentary, even dark forest is full of life. You will hear crickets, you will hear owls, you may see fireflies. The theory has catchy name, but even the earth's nature disproves it.
    - lambda_obrien 6y ago
      If you read the three books, you realize that the true message is that if you're considered a possible threat to an advanced species, they'll annihilate you, otherwise you'll be left alone. Maybe every other species which knows about us knows we can't even leave our own planet/moon right now, the most we can do is send useless robots to other planets over 30 years.
6gvONxR4sf7o 6y ago
There’s a nice analysis of the Fermi paradox out there somewhere that takes into account uncertainties in each of the parameters. As you multiply them together, the uncertainties compound each other. The end result is a big old who knows, rather than a paradox. Our observations are compatible with a really wide variety of realities, many of which include lots of aliens and many of which don’t.
shrimp_emoji 6y ago
A possible chink is that civilizations just don't do that -- carpet colonize the whole galaxy, or fill it with their probes to the extent that we seem them all over the place. The Fermi paradox relies on material (probes, colonies) and light (signals). With the material explained away, the lack signals is much easier to explain in that we haven't listened long and we can only hear very loud signals. (Or maybe advanced civs don't use light and use gravity waves or tachyon beams or whatever, but you don't even need to go that far.) The only way we hear a signal is if it's: 1. loud (high energy) and aimed directly at us, like a tight beam 2. EXTREMELY LOUD and aimed everywhere, isotropically 1 is unlikely since they'd have to know where we are; 2 is unlikely since you're talking about an insane level of energy. If it's the case that civs don't seem to be making Dyson spheres or harvesting whole galaxies for energy, being able to throw around that kind of power is prohibitively expensive. In both these cases, the inverse square law applies (for every unit x of distance, the light's x² less bright). Ironically, that means we're more likely to detect signals from an improbably close civilization (like 4 light years next door, in Alpha Centuari), than from farther away -- and even then, by a chance sweep of an umodulated asteroid scanning beam[0] or something, if we happened to be paying attention at the time. 0: https://en.wikipedia.org/wiki/BLC1 https://en.wikipedia.org/wiki/BLC1
- jrumbut 6y ago
  Do you know if about any simulations of what it would look like if there were alien radio operators? If there were 50 other Earths scattered around the galaxy (ones that have been broadcasting like us but for longer) should the first television have imnediately picked up interstellar "I Love Lucy" or would it be faint anomalies from SETI? Somewhere in between?
  - 7thaccount 6y ago
    The milky way is 100,000 light years across and I love Lucy is what, 60-70 years old? I would say we've reached a very small portion of the milky way
  - giantrobot 6y ago
    The inverse square law says no [0]. Even relatively high powered transmitters aren't detectable for an Arecibo-class antenna more than a few AU from Earth. If you want a signal detected light years away you need it to be highly directional. An isotropic radiator emitting enough power to be detected light years away is called a star. So any SETI signals we might detect would almost certainly need to be intentional. That doesn't mean they would need to be responses to something we've broadcast just the sender was aiming their transmitter towards the solar system and sent a signal. [0] https://web.archive.org/web/20140719094337/http://www.computing.edu.au/~bvk/astronomy/HET608/essay/ https://web.archive.org/web/20140719094337/http://www.comput...
gfodor 6y ago
Paradoxes are paradoxes precisely because they fail to disprove two contradictory claims. For the Fermi paradox, the paradox is that the immensity of the universe leading to life seems obvious, yet the complete absence of that life around us seems to show it's not there. So it disproves nothing, but actually highlights the difficulty of disproving either claim given the other.
- sli 6y ago
  I never much liked this being called a paradox since it has so many built in assumptions, most of them centered around any given, theoretical alien civilization resembling a human civilization in any way. It's a limitation of what we know for sure, since there's certainly no rule that civilization elsewhere should resemble civilization on Earth. That's an acceptable limitation, it's difficult to notice things you don't know you should notice, but it's a limitation nonetheless. Of course, it's also possible for civilizations to be so far away that we will like never detect them due to the inverse square law. They could even be in parts of the universe we can't observe.
stretchcat 6y ago
Every advancing civilization will eventually create an internet. Once they do that, interstellar travel is off the table. Advanced civilizations stay closely packed because they cannot tolerate latency once they get a taste for near instant communication.
- PaulDavisThe1st 6y ago
  Given that serious interstellar travel really requires FTL transport, I suspect that the two are rather closely connected.
  - willis936 6y ago
    Why is FTL necessary for interstellar travel? If you could go even 1% c then you could make journies that are multiple light years on the scale of centuries. It’s not until 50% c does time dilation start playing a significant role, but it would allow making a 10 l-yr journey in 17 years. Nature doesn’t care if we think there should be aliens or FTL travel. Nature doesn’t like casualty violated and that means we’re all going to be following its rules on the speed of causality. There are no cosmic-scale sentient forces that can shape space-time near us or else we would have noticed in observations decades ago.
  - stretchcat 6y ago
    I disagree, I think it probably would for humans.. but what about other advanced organisms? Maybe they have very long lives. Maybe their biology is more conducive to 'suspended animation' or some other form of hibernation. Maybe they've digitized their minds and can suspend execution of their thought processes for tens of thousands of years. Maybe their social traits (ant like hives perhaps?) make generation ships feasible while they would collapse into strive for humans.
  - _carbyau_ 6y ago
    So Competitive Quake/Counter Strike/ThingsKidsPlayTheseDays:-) will fund research into FTL transport for <1ms ping. Sadly, I could see it. Some billionaire somewhere wants "The Best" latency numbers and wants it on their yacht...
bobsmooth 6y ago
It really hasn't. [1] [1]https://arxiv.org/pdf/1806.02404.pdf https://arxiv.org/pdf/1806.02404.pdf

ncmncm 6y ago

Their best future course is to stop sniping at one another. It is possible that it's aliens. It is possible that it's not. We don't have enough evidence even to estimate probabilities, so anything further is pure speculation. Speculation is a look that wears no better on conservatives than on radicals. There is hardly a field to be found where young radicals are not promoting evidence for what the tenured consider anathema, waiting for the latter to retire or die and get the hell out of the way. As Max Planck said, "Science advances one funeral at a time." It is common to insist that the right idea wins in the end, but there is no reason to believe it: every case you can cite in its favor amounts to confirmation bias. The frequency of such examples that first languished for decades, with the original proposer driven from the field, would properly make us suspect that the majority of their also-correct peers remain unvindicated, however many false leads have been exposed. (Hypotheses promoted by women driven from a field make a rich vein of ideas to vindicate.) Loeb is right about one thing: the notion of "extraordinary evidence" is very destructive. Evidence is evidence. It is always easy to make greater demands on evidence you don't like than on evidence you do, and always easy find excuses to discount evidence incompatible with the consensus of the moment. Every field, to be considered legitimate, should maintain an officially taught compendium of "damned facts", evidence that seems to be incompatible with one or more leading theories. Even when a consensus theory is largely correct, the damned evidence will be the basis of any progress. Nature doesn't play favorites: it is possible for a consensus theory and all its challengers to be wrong. Evidence against one of the latter is not evidence in favor of the former.

6gvONxR4sf7o 6y ago
> Loeb is right about one thing: the notion of "extraordinary evidence" is very destructive. Evidence is evidence. I agree with pretty much everything you're saying except this. Though I still do agree with this a bit. It seems like a shorthand for "be bayesian" that's unfortunately taken too far too frequently. But if I have a strong prior one way or another, I will need stronger evidence to turn me around. +1 on your main point though. Why can't more people be more comfortable in a state of uncertainty ;_;
- ncmncm 6y ago

GlennS 6y ago

I think it's more that we know human nature, and we can see that people who believe we've been visited by aliens are engaging in story telling, not science. They're working back from the conclusion they want to be true, when they should instead start by weighing the evidence.