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Oh no I started a Fermi paradox thread! I don't have time for this but I'd suggest looking into other discussions on this. The Fermi paradox opens an entire mo

by api 10y ago

Oh no I started a Fermi paradox thread! I don't have time for this but I'd suggest looking into other discussions on this. The Fermi paradox opens an entire monstrous tree of possibilities, but it's not quite as simple as "there are no VN probes therefore there are no aliens." My two favorites are: (1) Interstellar travel might just be too damn hard. Going fast enough to get there in a reasonable time seems to require insane physicists' nightmare propulsion systems like antimatter or fusion rockets or artificial black hole drives, while taking too long means cosmic radiation has too much time to cook both organic matter and electronics... or you can't build a power source that will last that long, etc. (2) The "uniform cooling hypothesis" -- maybe life is common but intelligences able to build (or become) VN probes are so far incredibly rare. Since the entire universe is (according to the leading theory) the same age, such things simply haven't happened yet. (1) and (2) could work together-- maybe there are pretty advanced aliens everywhere but so far very few are advanced enough to attempt interstellar flight. If the probability of interstellar flight is less than, say, once per galaxy per billion years, then we would not see VN probes. Neither (1) nor (2) rules out signals at all.

pklausler 10y ago
I don't buy (1). B-vN probes don't care about transit time or cost. (2) is arguing for some kind of middle ground between "it's just us" and "lots of tech civs"; i.e., that life can get to the point of sending signals way easier than it can get to the point of launching a probe. But in our case the delta's just going to be a couple centuries, so no, that doesn't work for me either.
- TallGuyShort 10y ago
  Both your points assume a lot of knowledge about the future.
  - pklausler 10y ago
    They're reasonable extrapolations from current capabilities. Build a self-replicating 3-D printer, make it capable of finding and refining raw materials on asteroids, slap it on a Voyager-like slow interstellar platform, and off you go. (Yes, I'm being glib, but it's not that much of a stretch.)
    - TallGuyShort 10y ago
      Yeah but the energy efficiency required to pull that off? That's not just futuristic, that's astronomically close to violating physical laws...
    - inimino 10y ago
      "reasonable extrapolations" is a far cry from "airtight logical argument". But these discussions rarely seem to go anywhere...
- brenschluss 10y ago
  If you use the earth as an analogy: why isn't every island on the earth populated with people, since humans are probes, self-replicating beings that communicate with others? There's a lot of reasons there. Certain areas are unhabitable, or at least annoying to create a habitat (the arctic tundra, for example). Beings may want to cluster together (cities). There may be no interest in going to one territory over another - why bother spreading to all places, where there's so much out there? Finally, you could have situations in which a probe or a highly advanced civilization could deliberately not contact a lesser-advanced civilizations. How do we know that we're not the less-advanced civilization? See: https://en.wikipedia.org/wiki/Uncontacted_peoples https://en.wikipedia.org/wiki/Uncontacted_peoples
  - rdlecler1 10y ago
    Not every island is populated by people, but every island is populated with life. Any kind of self replicated probe should take on similar ubiquity.
  - pklausler 10y ago
    The thing about B-vN probes is that it just takes one.
    - disconcision 10y ago
      I'm not sure how this is a counter to the human analogy? I'm assuming you're assuming probes reproduce and propagate perfectly, but if we assume a 'human reproductive unit' (be it a pregnant individual, a couple, a minimum viable population, whatever) has perfect genetics which can be perfectly replicated, then 'it just takes one' as well. While some sort of b-vn scenario seems plausible, at this point in technological development the practical contingencies of such a scheme are pretty up in the air. I mean, look at it from the other end. If we assume arbitrary technological progress, it's possible probes are everywhere, but we wouldn't even recognize them as technological artifacts if we were starring directly at them.
pault 10y ago
My favorite theory is an extension of #1: interstellar travel is so expensive and difficult that advances in AI and virtual reality make it undesirable. There's no point in spending a non-trivial fraction of your civilization's resources colonizing another solar system when you can do anything you want at arbitrary time scales in a simulation.
credit_guy 10y ago
One other possible solution to the Fermi paradox is that the aliens exist, but they leave us alone, just like the Indian government leaves the Sentinel people alone.

by api 10y ago

pklausler 10y ago

I don't buy (1). B-vN probes don't care about transit time or cost. (2) is arguing for some kind of middle ground between "it's just us" and "lots of tech civs"; i.e., that life can get to the point of sending signals way easier than it can get to the point of launching a probe. But in our case the delta's just going to be a couple centuries, so no, that doesn't work for me either.

TallGuyShort 10y ago
Both your points assume a lot of knowledge about the future.
- pklausler 10y ago
  They're reasonable extrapolations from current capabilities. Build a self-replicating 3-D printer, make it capable of finding and refining raw materials on asteroids, slap it on a Voyager-like slow interstellar platform, and off you go. (Yes, I'm being glib, but it's not that much of a stretch.)
  - TallGuyShort 10y ago
    Yeah but the energy efficiency required to pull that off? That's not just futuristic, that's astronomically close to violating physical laws...
  - inimino 10y ago
    "reasonable extrapolations" is a far cry from "airtight logical argument". But these discussions rarely seem to go anywhere...
brenschluss 10y ago
If you use the earth as an analogy: why isn't every island on the earth populated with people, since humans are probes, self-replicating beings that communicate with others? There's a lot of reasons there. Certain areas are unhabitable, or at least annoying to create a habitat (the arctic tundra, for example). Beings may want to cluster together (cities). There may be no interest in going to one territory over another - why bother spreading to all places, where there's so much out there? Finally, you could have situations in which a probe or a highly advanced civilization could deliberately not contact a lesser-advanced civilizations. How do we know that we're not the less-advanced civilization? See: https://en.wikipedia.org/wiki/Uncontacted_peoples https://en.wikipedia.org/wiki/Uncontacted_peoples
- rdlecler1 10y ago
  Not every island is populated by people, but every island is populated with life. Any kind of self replicated probe should take on similar ubiquity.
- pklausler 10y ago
  The thing about B-vN probes is that it just takes one.
  - disconcision 10y ago
    I'm not sure how this is a counter to the human analogy? I'm assuming you're assuming probes reproduce and propagate perfectly, but if we assume a 'human reproductive unit' (be it a pregnant individual, a couple, a minimum viable population, whatever) has perfect genetics which can be perfectly replicated, then 'it just takes one' as well. While some sort of b-vn scenario seems plausible, at this point in technological development the practical contingencies of such a scheme are pretty up in the air. I mean, look at it from the other end. If we assume arbitrary technological progress, it's possible probes are everywhere, but we wouldn't even recognize them as technological artifacts if we were starring directly at them.

pault 10y ago

My favorite theory is an extension of #1: interstellar travel is so expensive and difficult that advances in AI and virtual reality make it undesirable. There's no point in spending a non-trivial fraction of your civilization's resources colonizing another solar system when you can do anything you want at arbitrary time scales in a simulation.

credit_guy 10y ago

One other possible solution to the Fermi paradox is that the aliens exist, but they leave us alone, just like the Indian government leaves the Sentinel people alone.