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Please explain because i would intuit the opposite. The less life's we see, the less likely that life survives to/through technological ages that would allow th

Please explain because i would intuit the opposite. The less life's we see, the less likely that life survives to/through technological ages that would allow them to talk to us. If we see abundant life the it must be very easy to survive, thus less filters

pfdietz 2y ago
If life is abundant, there must have been something to prevent it from spreading, now or in the distant past. The fact that we evolved in an apparently empty universe, rather than in one that's been totally colonized, implies something stops this from happening. This thing is called the Great Filter, and it's apparently extremely effective. If the GF is in front of us, in a universe with lots of ETI, our chances of evading it are extremely small. After all, no one else has; why would we be so special? Nick Bostrum has called detection of ETI, or even complex ET life, the worst news mankind would ever receive. It would be a death sentence for our future. https://nickbostrom.com/papers/where-are-they/ https://nickbostrom.com/papers/where-are-they/
- svnt 2y ago
  You can have abundant life that is functionally isolated by physics, or said differently, by the degree of technological and societal advancement required to traverse the space between. Great distances and inherent speed limits seem like a decent way to accomplish that.
  - pfdietz 2y ago
    I think it's clear that interstellar travel, while not trivial, should be possible for a civilization just a bit more advanced than our own. The energy or material resources required for interstellar colonization are very small compared to the resources available. It doesn't even require relativistic speeds, although reaching (say) 0.01 c doesn't require outrageous engineering, just a large spacecraft and lots of hydrogen bombs. Now, perhaps it's universally true that civilizations don't advance much beyond where we currently are, or don't persist for sufficiently long for interstellar colonization to be successful. These would also be very depressing outcomes if they are imposed on us by the GF.
    - rbanffy 2y ago
      Interstellar colonization is more difficult than it's commonly imagined. To build a colony ship you need the same resources you'd need to build a large habitat. There would be economic pressure to build habitats that'd compete with the building of colony ships. When a colony ship arrives to a new planet, it'll need to bootstrap a full industrial chain before it can build its own colony ships to expand to other systems. It's reasonable to assume there would be little incentive for that before the colony starts to require off-planet resources on their own system, and, therefore, has a compelling reason to build a space economy. For us, this would easily be in the thousands of years even if no terraforming is needed, and let's not even consider we'd need a consistent multi-century planning to get there. Precursor missions with automated in-situ resource collection and storage would allow colonists to arrive to a fully built and stocked colony, which would save some time. Existing biospheres might present issues of toxicity and biological risks: you really don't want to grow up on a (Dune's) Rossak (even if it grants you superpowers). So, let's say Earth manages to establish 10 successful extra-solar colonies over 5 thousand years. It'll be at least a good couple thousand years until those successful colonies can each establish 10 others and raise the number to 100 worlds. If we manage to diligently expand at that exponential ration, we'll soon bump into other intelligent space-faring species that also share this commitment to reproduce.
      - svnt 2y ago
        And what motivates the continued expansion? Exhaustion of resources, if that is it, means that decay immediately eats into your reproduction and it isn’t a proliferation, but at best a continuous parasitic migration.
    - svnt 2y ago
      I don’t think that is clear at all. I think it reflects a massive gap in understanding of how difficult it is to do anything with humans for more than a generation.
- api 2y ago
  Space is called space for a reason. I feel like even scientifically knowledgeable people have a hard time wrapping their heads around just how much space is out there. Here's a good place to start: https://joshworth.com/dev/pixelspace/pixelspace_solarsystem.html https://joshworth.com/dev/pixelspace/pixelspace_solarsystem.... Signals diminish with the square of distance. SETI would never hear anything from other stars unless it was broadcast with insanely high transmit power or was directed right at us (and still very powerful). Nobody would do that unless they knew someone was here actively listening. https://briankoberlein.com/blog/et-phone-home/ https://briankoberlein.com/blog/et-phone-home/ So for example, to reach the Centauri system (the nearest star) with a signal as powerful as the signal Voyager sends to Earth would require a transmit power of over 100 megawatts at a minimum. That's just the nearest star. It gets exponentially harder as you go further out. For more distant stars you're talking gigawatts or terawatts or beyond. Even barring concerns about attracting attention, why dedicate that kind of resources to operate an interstellar border blaster if you don't even have a reason to think anyone's listening, and if you won't get a reply for hundreds or thousands of years?
  - pfdietz 2y ago
    This is not making a point you think it's making. If SETI is problematic, success becomes even more depressing, since it implies even more non-communicating civilizations out there (and, presumably, existing densely in the past as well). So why wasn't Earth colonized eons ago?
    - api 2y ago
      Why would it be? It’s full of corrosive oxygen and biomass that would be a biohazard to anything carbon based and organic. It’s habitable to us because we evolved here but it might be toxic hell to something else. If you are going to sterilize Earth you might as well just terraform something dead. This isn’t even getting into the ethical questions, just looking at practicality. If you’ve got the technology to come here, well, you might as well terraform something dead. We almost have the technology to terraform Mars (albeit over thousands of years) and it seems easier to do and possibly faster than interstellar flight. Building giant space station habitats is also easier than interstellar flight. Uploading brains to machines, which would allow settlement of almost anywhere, is probably easier than interstellar flight. AGI is probably easier than interstellar flight. In fact interstellar flight is so hard it might rarely be attempted anywhere by anyone unless there’s a forcing function like one’s star becoming unstable or some other cosmic scale calamity. Solar systems are huge and contain vast amounts of resources.

pfdietz 2y ago

If life is abundant, there must have been something to prevent it from spreading, now or in the distant past. The fact that we evolved in an apparently empty universe, rather than in one that's been totally colonized, implies something stops this from happening. This thing is called the Great Filter, and it's apparently extremely effective. If the GF is in front of us, in a universe with lots of ETI, our chances of evading it are extremely small. After all, no one else has; why would we be so special? Nick Bostrum has called detection of ETI, or even complex ET life, the worst news mankind would ever receive. It would be a death sentence for our future. https://nickbostrom.com/papers/where-are-they/ https://nickbostrom.com/papers/where-are-they/

svnt 2y ago
You can have abundant life that is functionally isolated by physics, or said differently, by the degree of technological and societal advancement required to traverse the space between. Great distances and inherent speed limits seem like a decent way to accomplish that.
- pfdietz 2y ago
  I think it's clear that interstellar travel, while not trivial, should be possible for a civilization just a bit more advanced than our own. The energy or material resources required for interstellar colonization are very small compared to the resources available. It doesn't even require relativistic speeds, although reaching (say) 0.01 c doesn't require outrageous engineering, just a large spacecraft and lots of hydrogen bombs. Now, perhaps it's universally true that civilizations don't advance much beyond where we currently are, or don't persist for sufficiently long for interstellar colonization to be successful. These would also be very depressing outcomes if they are imposed on us by the GF.
  - rbanffy 2y ago
    Interstellar colonization is more difficult than it's commonly imagined. To build a colony ship you need the same resources you'd need to build a large habitat. There would be economic pressure to build habitats that'd compete with the building of colony ships. When a colony ship arrives to a new planet, it'll need to bootstrap a full industrial chain before it can build its own colony ships to expand to other systems. It's reasonable to assume there would be little incentive for that before the colony starts to require off-planet resources on their own system, and, therefore, has a compelling reason to build a space economy. For us, this would easily be in the thousands of years even if no terraforming is needed, and let's not even consider we'd need a consistent multi-century planning to get there. Precursor missions with automated in-situ resource collection and storage would allow colonists to arrive to a fully built and stocked colony, which would save some time. Existing biospheres might present issues of toxicity and biological risks: you really don't want to grow up on a (Dune's) Rossak (even if it grants you superpowers). So, let's say Earth manages to establish 10 successful extra-solar colonies over 5 thousand years. It'll be at least a good couple thousand years until those successful colonies can each establish 10 others and raise the number to 100 worlds. If we manage to diligently expand at that exponential ration, we'll soon bump into other intelligent space-faring species that also share this commitment to reproduce.
    - svnt 2y ago
      And what motivates the continued expansion? Exhaustion of resources, if that is it, means that decay immediately eats into your reproduction and it isn’t a proliferation, but at best a continuous parasitic migration.
  - svnt 2y ago
    I don’t think that is clear at all. I think it reflects a massive gap in understanding of how difficult it is to do anything with humans for more than a generation.
api 2y ago
Space is called space for a reason. I feel like even scientifically knowledgeable people have a hard time wrapping their heads around just how much space is out there. Here's a good place to start: https://joshworth.com/dev/pixelspace/pixelspace_solarsystem.html https://joshworth.com/dev/pixelspace/pixelspace_solarsystem.... Signals diminish with the square of distance. SETI would never hear anything from other stars unless it was broadcast with insanely high transmit power or was directed right at us (and still very powerful). Nobody would do that unless they knew someone was here actively listening. https://briankoberlein.com/blog/et-phone-home/ https://briankoberlein.com/blog/et-phone-home/ So for example, to reach the Centauri system (the nearest star) with a signal as powerful as the signal Voyager sends to Earth would require a transmit power of over 100 megawatts at a minimum. That's just the nearest star. It gets exponentially harder as you go further out. For more distant stars you're talking gigawatts or terawatts or beyond. Even barring concerns about attracting attention, why dedicate that kind of resources to operate an interstellar border blaster if you don't even have a reason to think anyone's listening, and if you won't get a reply for hundreds or thousands of years?
- pfdietz 2y ago
  This is not making a point you think it's making. If SETI is problematic, success becomes even more depressing, since it implies even more non-communicating civilizations out there (and, presumably, existing densely in the past as well). So why wasn't Earth colonized eons ago?
  - api 2y ago
    Why would it be? It’s full of corrosive oxygen and biomass that would be a biohazard to anything carbon based and organic. It’s habitable to us because we evolved here but it might be toxic hell to something else. If you are going to sterilize Earth you might as well just terraform something dead. This isn’t even getting into the ethical questions, just looking at practicality. If you’ve got the technology to come here, well, you might as well terraform something dead. We almost have the technology to terraform Mars (albeit over thousands of years) and it seems easier to do and possibly faster than interstellar flight. Building giant space station habitats is also easier than interstellar flight. Uploading brains to machines, which would allow settlement of almost anywhere, is probably easier than interstellar flight. AGI is probably easier than interstellar flight. In fact interstellar flight is so hard it might rarely be attempted anywhere by anyone unless there’s a forcing function like one’s star becoming unstable or some other cosmic scale calamity. Solar systems are huge and contain vast amounts of resources.