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Fermi Paradox Predicting Humankind's Future?

An anonymous reader writes "The Fermi paradox says that if extraterrestrial civilizations exist, at least one of them should have colonized the entire galaxy by now. But since there is no evidence of this, humankind must be the only intelligent life in the galaxy. The Space Review has an article on how the Fermi paradox can be applied to human civilization. It says that, like the extraterrestrials, humans have three choices: colonize the galaxy, remain on Earth, or become extinct."

13 of 854 comments (clear)

  1. More likely by Maxo-Texas · · Score: 4, Interesting

    The speed of light is a real and unbreakable rule as a result nothing more than 4 or 5 light years away is reachable.

    Sure- you *might* be able to theoretically build a ship that could go further but all politics is local. Look at our politics- could we gather the will to build a 10 trillion dollar multi-generation star ship?

    I think civ's do okay, never get off the planet the started on, and eventually die out from lack of resources, some kind of self destruction, or being wiped out by an external event.

    --
    She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
    1. Re:More likely by peragrin · · Score: 4, Interesting

      While the speed of light may be constant it doesn't mean there aren't other ways around the problem.

      Let's figure out how first.

      Besides why would an alien race need the whole galaxy? A small section would do. Even so they could have died out millions of years ago. Or we could be the first advanced race and as we reach out amoung the stars we shall find other less advanced races.

      --
      i thought once I was found, but it was only a dream.
    2. Re:More likely by AJWM · · Score: 4, Interesting

      The speed of light is a real and unbreakable rule as a result nothing more than 4 or 5 light years away is reachable.

      The Fermi Paradox assumes the light-speed limit.

      There are an awful lot of hidden assumptions in your bald statement that the speed of light automatically limits travel to a range of 4 or 5 ly. Why not 3, or 6, or 10? It doesn't take much to allow for hops from one star to the next, and if you've got the tech to build starships, you've got the tech to colonize a star system that doesn't have Earthlike planets. (Ie space colonies, not terraforming - although the latter may also be possible.)

      I think civ's do okay, never get off the planet the started on, and eventually die out from lack of resources,

      Quite likely a civilization that never gets off its home planet will eventually run out of resources. But there are resources aplenty for those that take that first step. That's why people talk about He3 mining, solar powersats, mining asteroids, etc. Remember O'Neill's question: "Is the surface of a planet the right place for an expanding industrial civilization?" The answer is "no".

      --
      -- Alastair
    3. Re:More likely by SatanicPuppy · · Score: 4, Interesting

      The problem is, expansion is driven by population pressure. The kind of space travel you're theorizing wouldn't do a damn thing to relieve local population pressure, so it would be more of a sort of species level masturbation, to send out ships to make colonies that are so far away that you'd never be able to engage in any sort of trade or cultural exchange.

      --
      ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
    4. Re:More likely by quadelirus · · Score: 4, Interesting

      I don't think Fermi is talking about mere visits, but colonization. If so, we wouldn't have to worry about them missing us, because if they had come, they would have stayed. To quote the wikipedia article: "The second cornerstone of the Fermi paradox is a rejoinder to the argument by scale: given intelligent life's ability to overcome scarcity, and its tendency to colonize new habitats, it seems likely that any advanced civilization would seek out new resources and colonize first their star system, and then surrounding star systems. As there is no evidence on Earth or anywhere else of attempted alien colonization after 13 billion years of the universe's history, either intelligent life is rare or assumptions about the general behavior of intelligent species are flawed."

    5. Re:More likely by SnowZero · · Score: 4, Interesting

      I dunno, if I were an alien race, and had the choice of colonizing solar systems where the best planet was:
      (1) Teeming with constrantly mutating alien bacteria
      (2) Lifeless and ready for terraforming

      I know which one I would choose. Seriously, why risk alien disease when there are so many "clean" places to choose from? If you were looking for a cave to sleep in, would you choose the empty one or the one with animals already in it? Unless space travel is instant, I really don't see a race ever expanding fast enough to need to use every planet. Besides, it is selfish to think alien life is "as we know it" and would even care about our planet; If they aren't water-based our planet could seem like the same kind of hell that Venus seems to us.

  2. Only two choices. by AJWM · · Score: 4, Interesting

    "Remain on Earth" and "become extinct" are not distinct choices. As Heinlein and numerous others have put it, the Earth is too small and fragile a basket for humanity to keep all its eggs in.

    It's not so much a matter of "if" but of "when". Ask the dinosaurs.

    --
    -- Alastair
  3. Re:Remain for how long? by nurb432 · · Score: 4, Interesting

    The universe wont last forever either.

    --
    ---- Booth was a patriot ----
  4. The paradox with the paradox by twifosp · · Score: 4, Interesting
    The math used in the paradox is flawed. It only contains a linear probability using only one variable: quantity. Wikipedia states that there are an estimated 250 billion visible stars in the milky way and 70 sextillion in the visible universe. What it does not take into consideration is time. For every lightyear of distance a potential life carrying solar system away from Earth is, a year is subtracted from the amount of time it took that potential system to reach space maturity.

    In other words, it has taken primates some-odd half a million years to evolve into humans capable of inventing devices that can decipher energy waves from space. It has taken the Earth some 200 million years (from early life to humans) to evolve life on this scale. Assuming other planets have roughly the same time scale, we can only assume those planets inside a 200 (give or take a 100) million lightyear radius contains no life.

    The paradox with the paradox is as follows: Earth contains intelligent life. Earth has not colonized the galaxy. Earth's evidence in space only reaches back into the 1930s when the very first signals were sent into space.

  5. "The Great Filter - Are We Almost Past It?" by Jerf · · Score: 5, Interesting

    For what I consider a much better treatment of this topic, see: The Great Filter - Are We Almost Past It?

    This stuff is a big deal, and the Great Filter paper actually manages to draw some useful concrete conclusions from the question, or at least useful concrete questions.

    Also related, albeit a little more tangentially, is "Are You Living In A Computer Simulation?". "We're in a simulation and there are no extraterrestrials in the simulation" must be considered one of the leading possible answers. (I'm not advocating it either way, I don't have an answer. Nor do I consider this post anywhere near a complete list, just some relevant pointers.)

  6. NOT being honest! by ScentCone · · Score: 4, Interesting

    we're too small minded to colonise the galaxy

    We weren't too small minded to risk lives hiking over mountain ranges or floating in very-likely-to-sink boats across open ocean to other continents, remember? Primitive Asians floating across the Pacific to populate South America or hoofing it in across the northern straights were taking on something at least as dicey as we currently see activities in space. Villages wiped each other out, disease killed off whole tribes - all of the stuff that people say would keep us from colonizing elsewhere. Sure, some of those efforts would fail - just as they have for tens of thousands of years. But some will succeed, too.

    we use our resources to make trivial things that amuse us for a short period of time (ipod, iphone, etc)

    That's because we evolved from, and still are short-lived primates. Our brains were wired to deal with much more short-term issues. Planning through the coming weather change is about as far as we ever needed to go, mentally. Only some people have the wiring to do big picture stuff... and guess what: they tend to get jobs doing big picture stuff. As for trivial things like iPods: you'd rather have a society with somewhat better antibiotics, but completely absent all of the things that make life a pleasure? The iPod is just a newer take on cave painting and tribal dancing. The fact that we evolved into creatures that put handprints on walls and invent group songs to sing doesn't mean we can't also do things like invent solar cells, fly transplant organs through the air to another city where they're needed, or manage to live past 25. Being productive, inventive, and joyous are not mutually exclusive - they're interdependent.

    rather than doing useful things (cure diseases, etc).

    I'm sorry to hear that you died of Polio. Or was it Smallpox? Or maybe spoiled food because we haven't invented refridgeration yet. Anyway, sorry you died.

    --
    Don't disappoint your bird dog. Go to the range.
  7. Re:Fermi paradox by Pedrito · · Score: 4, Interesting

    I agree with this parent post. It's pretty silly to assume that "if space faring civilizations exist, they should have colonized the ENTIRE galaxy by now." What about evolution time? Time to develop technology? Time to establish colonies? etc etc etc.

    Actually, the Fermi Paradox takes all that into consideration. The time to colonize the galaxy, once a species has become space faring is minuscule in comparison to evolution. The paradox is based on the idea that the space faring civilization will colonize the galaxy before other species have a chance to evolve and the probability of two space faring civilizations existing at the same time is incredibly low.

    If another civilization were to have started colonizing the galaxy, it's unlikely it would have been in the time periods you point out, 10,000, 20,000 years ago. It's more likely they would have begun tens to hundreds of millions of years ago, and yes, that is enough time to colonize the entire galaxy.

    The Earth is believed to be about 4.6 billion years old. Life emerged in the first few hundred million years, probably around 4 billion years ago. Multicellular life sprung up around 1 billion years ago. Mammals have been around for about 200 million years. Homosapiens started out, probably around 200 million years ago. Now, let's say that instead of taking 3 billion years to go from single cell to multi-cell, it only took 2.5 billion years. That's a 500 million year head start. And there's no reason to think that's impossible. It's believed that the evolution of multi-cell was likely a fluke and not necessarily a forgone conclusion, largely because it took so long to show up. So that "fluke" could have probably happened any time after single-celled life began (well, any time after the first few hundred million years of it, at least).

    Also, intelligence isn't necessarily a forgone conclusion of evolution. Dinosaurs had a lot more time to evolve than we have and they never developed our kind of intelligence. So let's say an animal in the dinosaur period had developed intelligence. That was over 65 million years ago. Plenty of time to colonize the galaxy.

    The time to colonize the galaxy would, with only modest technological advancement from where we are now, would probably be a few million years. A very thin line on the timeline of evolution.

  8. The Fermi growth assumes uncontrolled growth by vidarh · · Score: 4, Interesting
    As we can ALREADY see, some mechanism is at least in humans reducing population growth in the parts of the population that have reached a certain level of social safety: Most developed nations are seeing sub-replacement level birth rates. In countries who have not yet reached this stage, we are seeing mass deaths and low life expectancies. And it's worth noting that this is not cultural either - immigrants moving to developed countries typically adapt to the host nations birth rate patterns within 1-3 generations.

    So a simple possible answer to the Fermi paradox is that this is an inherent biological mechanism and that in any population that grows to fill its biological niche, birth rates will sooner or later drop until an equilibrium is reached, and this is likely to happen before there is significant pressure to colonize the nearby solar system or stars. While that would leave visits to other planets still reasonably likely, and perhaps even small "local" colonies, without an expanding population and diminishing resources driving prices up, pure economics would dramatically slow down the tempo of any colonization effort to what private individuals could afford and would want to try.

    Look at how long Europeans had the capability to reach America before the wave of colonization started, for example. This was a set of cultures that were aggressive and expansionist. Assume the drive to start colonization gets successively less likely as the cost of doing so goes up and the immediate benefit of doing so drops. Once it takes more than a lifetime for economic value to be derived from a colony due to travel time even at light speed, the motivation for pushing for it dramatically reduces for most individuals (look at how hard it is getting people to even sacrifice spending today vs. getting a good pension until they're getting to a certain age, not to consider getting people to sacrifice now for the benefit of their children).

    Even with dramatic population growth, a colony would either have to bring economic value (in the form of resources) OR cost little enough in terms of resources to initiate and transfer colonists to than leaving the people the colony would have been made up of in place for a long enough amount of time to make giving up those resources seem prudent. If improvements in how we exploit various resources keep improving, that in itself might put a significant damper on any colonization efforts.

    That leaves us with possibly the odd colony here and there or the odd probe. Small colonies would face high odds of dying off, and would be unlikely to be established far away - presumably nearby stars would be targeted. Unless these colonies then enter an aggressive expansionist phase, and either had the technology to pull it off (provide resources for itself) or had the fortune of finding a location that provides abundant resources, it would take a lot of time before such a colony could produce offshoots further away. Chances are they'd grow to fill their new solar system first, and run into the same hypothetical growth reductions as we're currently seeing with developed countries on earth.

    That leaves radio. Why haven't we heard radio chatter? Stephen Baxter suggested a simple solution in the novel "Space": IF there are aliens out there, we might not want to make a big fuss about our existence, and also, a civilization may simply grow past broadcasting (That book does also, btw. pose an alternative explanation for the Fermi paradox, but stating it here would be a huge spoiler - it's a good read). We might already be nearing the time where we'll "go silent", as technological advance continues. Given the number of possible stars, how short time we've been listening, and how short periods potential civilizations may broadcast, it's very possible that there just aren't enough civilizations at the right stage of development that their radio chatter happened to intersect with the time periods we are currently monitoring. We may for that