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Should The Galaxy Have Been Colonized By Now?

  1. Oct 26, 2005 #1
    This topic brings up the Fermi Paradox, once again. I just want to hear the boards opinion on this...should the galaxy have been colonized by now? and a decent portion of it has been colonized would we able to "see" it?
     
  2. jcsd
  3. Oct 27, 2005 #2
    what if we're the first space faring civilization? The galaxiy would still be a very lonely isolated place. my point is it's impossible to tell at this moment.

    I doubt it, which brings me back to my first point, our technology is still very primitive.
     
  4. Oct 27, 2005 #3
    So we are still very much in the dark, is that what you mean?

    EDIT: What do you guys think of this quote

    "Quote from Freeman Dyson;
    "I have the feeling that if an expanding technology had ever really got loose in our galaxy, the effects of it would be glaringly obvious. Starlight instead of wastefully shining all over the galaxy would be carefully dammed and regulated. Stars instead of moving at random would be grouped and organized . . . So in the end I am very skeptical about the existence of any extraterrestrial technology."
     
    Last edited: Oct 27, 2005
  5. Oct 27, 2005 #4
    Yes, and in regards to astronomical engineering well lets just say that the technologies to accomplish some of those feats would require a lot of power and a lot of time (thousands or millions of years) But I very much doubt that anyone would bother going to all the trouble of arranging stars in an organized manner, seems to me there are more worthwhile goals to undertake, whatever they may be.
     
  6. Oct 27, 2005 #5

    Chronos

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    Agree with vast. Assuming our scientific knowlededge is even marginally correct, interstellar travel is too expensive to justify. Colonizing the galaxy to any appreciable extent could easily take many billions of years.
     
  7. Oct 27, 2005 #6
    According to this site, we could colonize the MW in like 500 or so years...http://home.comcast.net/~mbmcneill7/ [Broken]

    is this bull or is it plausible
     
    Last edited by a moderator: May 2, 2017
  8. Oct 27, 2005 #7

    Garth

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    As it will take 100,000 years or so to send a light ray across the MW I would say those figures are a little optimistic. Are you sure the '500 years' was not the estimated time to return to the Moon?

    Garth
     
  9. Oct 27, 2005 #8
    This is assuming, of course, extraterrestial civilizations even want to colonize the galaxy. For all we know they could be just happy just living on their home world.
     
  10. Oct 27, 2005 #9
    Yes, of course...or just their own solar system.
     
  11. Oct 27, 2005 #10
    Earth-like planets require a certain amount of galactic distillation to occur before such planets can form. First, an initial generation of stars have to cook up the heavy elements needed for rocky planets and life. These elements are spread around through supernova, and then another generation of stars has to form from the resultant dust. However, the inner part of the galaxy is too dangerous for life to exist very long: there are supernova constantly exploding at close range, and the density of stars and black holes would disrupt the orbits of any planets that form. Thus, only the middle and outer regions of the galaxy are suitable for life. But stellar evolution proceeds more slowly as one travels toward the edge of the galaxy because the mass density decreases. Consequently, Earth-like, rocky planets capable of supporting life will begin to form in a ring around the middle of the galaxy that spreads to the edge through time. Through an accident of galactic geography, we happen to be on the inner edge of this ring, which entails that we are among the first planets with life, and perhaps the very first planet in the galaxy to have human-style intelligence—as the negative results of the SETI project tend to bear out, sporadic reports of UFO’s notwithstanding.
     
  12. Oct 27, 2005 #11
    If that theory is correct then there still should be a couple dozen or more Earth-like planets with life on it with intelligence close to ours or maybe even surpassing us by a couple thousand years, even if it is still early in the game and we are the first wave, there should be more like us...theres just way too many stars.

    Even though I dont think the lack of alien signals points to this theory being correct.
     
    Last edited: Oct 27, 2005
  13. Oct 27, 2005 #12
    Well, if human-style or higher intelligence and culture is so easy to evolve, one or more species of dinosaurs should have evolved into a technological civilization. But this didn't happen, despite the fact that there were many bipedal species of dinosaurs with free forelimbs.

    Similarly, primates have been around for 10's of millions of years; if it is easy to evolve intelligence, there should have been another primate species that evolved long ago.

    Other contingencies also *could* have happened on Earth that would have made it much harder to evolve human-style intelligence; e.g., if the original vertebrate ancestor had gone extinct, there would be no vertebrates at all. On a planet with Earthly gravity, it is difficult to grow very large land arthropods, because of their external skeleton. Maybe lobsters or octopi could become very intelligent, but it would be difficult to get a technological civilization started in seawater.

    Of course, the other standard explanation for the great silence is that technological civilizations are extremely unstable and quickly blow themselves up. Thus, the odds of any two technological civilizations existing at the same time would be vanishingly small.

    Or perhaps there is one dominant, yet very stealthy civilization that destroys any new civilization that it detects, in order to preserve it's turf--and they're on their way. . . .
     
  14. Oct 27, 2005 #13

    Labguy

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    Yes, but if we are considering "civilizations" that can evolve, reason and use technology, it isn't just going to be limited to Earth-like planets. Not all possible evolutions are going to become two-legged, 5-foot 10-inch bipeds walking around with simply different patterns of bumps and spots on their heads, as in Star Trek.
    There could be creatures the size of a flea, breathing H2SO4 and flying in ships the size of a shoebox....:zzz:

    Yes, they are called the BORG, again as in Star Trek.
     
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  15. Oct 27, 2005 #14
    Or maybe we are still very much in the dark, its not like we scanned the a decent portion of the galaxy already, there could be a civilization 1000 light years from us and we might not know it right now...and I never said developing human-like intelligence was easy but it did happen, even if it is rare there should be atleast a dozen or more like us because of how many stars there are. I dont think the great silence proves that there arent any aliens out there...atleast not yet.
     
  16. Oct 27, 2005 #15
    No that is quite unlikely. Aliens have to follow the laws of physics and something the size of a flea doesn't have the brain power to make a spaceships.

    Just so you know, the fact that there are a lot of stars in the universe, doesn't at all imply life is out there.
     
  17. Oct 27, 2005 #16

    Labguy

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    That wouldn't constrict the possibility of micro-neurons in micro-branes. The don't have to be built with cellular construction like ours. It is possible.:biggrin:
    Perhaps not, but here we sit contemplating the subject with computers. The huge number of stars in billions of galaxies makes it rather egotistical of our race to think that we are it; nothing else. "The stars and all the universe revolve around us", said Galileo to the inquisitor...:cry:
     
  18. Oct 27, 2005 #17
    Micro-"branes"--as in 11-dimensional p-branes?:confused: An interesting suggestion; but how could biological-like evolution through natural selection occur at such tiny scales? Think about Von Neuman's essential elements for *any* self-replicating system. What would be the mode of heredity? What would the bodies be like? How do branes control other branes? Can branes make copies of themselves? What would an ecosystem in 11-dimensional hyperspace be like? If it really is possible for branes to be intelligent, space-faring creatures, then where are they?

    So yeah, I still like Star Trek--at least the original version. I graduated from "Horton hears a Who" a long time ago. :bugeye:
     
    Last edited: Oct 27, 2005
  19. Oct 27, 2005 #18

    Labguy

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    I never said I could spell..:mad:
    Brane, Brain, Calabi-Yau loops??.:confused:
    Poor old Brian Greene and String theory don't have a chance.
    I graduated from infinities and singularities a long time ago.
     
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  20. Oct 28, 2005 #19
    I never said it was impossible, just very unlikely given the knowledge we have, which it is. This is a forum of science, not science-fiction.

    Not egotistical, just illogical. And I think it was the inquisitor that said that to Galileo, not the other way around.
     
  21. Oct 28, 2005 #20

    Labguy

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    Yes, it is science, so wouldn't it be absurd to exclude things / properties / possibilities which we simply haven't discovered yet? Were Einstein, Oppenheimer, Chandra, Eddington, et al doing science fiction when considering the possibilities of strange objects like neutron stars and black holes? I think that it was ~1966 when the Crab pulsar was detected, a fair bit after the initial thinking and even the math regarding such strange objects. Chandra's Limit for example?
    No, Galileo had to say it to "recant", and then spend the rest of his life under "house arrest".
     
  22. Oct 28, 2005 #21
    it is clear to me- when considering our rapid acceleration from harnessing fire to nanotechnology and quantum computing in just a few hundred generations- that any intelligent civilizations that survived their planetary infancy would almost certainly have progressed to a point where their entire technological civilizations and all of their assets would operate from only a negligible quantity of matter- a diffuse nebular utility fog of nano/femtotechnology and quantum computing networks containing the equivalent of trillions of worlds and quintillions of minds- yet with little to no physical substrate whatsoever-

    less than half a century from the invention of the transistor and this sort of 'instrumentality free' existence already looks like our near future- if we survive- computation is inherent in intelligence and technology- and the laws of physics show that matter is capable of computation many many many orders of magnitude beyond the structures we find in nature such as planets and ecosystems and human brains- there is no reason to believe that aliens would build great space industrial engineering or vast industrial activity that could be detected from beyond their star system- in fact it would be doubtful that someone like a human would be able to even see an alien- or it's civilization and technology if he were literally standing right in front of it!
     
    Last edited: Oct 28, 2005
  23. Oct 28, 2005 #22

    SpaceTiger

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    If it does hold true, then who's to say they haven't colonized the galaxy. If they were that far advanced, I suspect they would have no trouble escaping our view (if they so desired). Another thing to consider is that, although it's possible for an advanced race, is it necessarily to their advantage to colonize the galaxy? Perhaps it's too much effort for too little gain.

    I do think that, at the current rate of advancement, we could colonize the galaxy someday. However, that is only if we don't destroy ourselves first. It seems extremely likely that we will do that in the near future.
     
    Last edited: Oct 28, 2005
  24. Oct 28, 2005 #23
    No because they came to logical conclusions with the infomation they had, while you're only support is "anything is possible, so so-in-so could be true." While Galileo had mathamatical and documented evidence that the planets revolved around the sun. To compare Galileo's harsh persecution to my counter-argument is not only insulting to Galileo, but also belittling to myself. And just so you know I could easily imply "anything is possible, therefore ghosts could exist, despit all the evidence to the contrary." Does that sound like science to you?

    I don't get what you're saying. Planets and ecosystems don't compute anything. And what 'type' of matter (that we know of) is capable of more computations that the human brain?



    Why!? What evidence do you have to support this claim? I can't see individual transitors, but I can see the computer their in. Simply because aliens can produce incredible small technologies, doesn't imply they still won't have marcoscopic ones. Look at progress of human civilization, is technology more apparent now or a thousand years ago? Look at our skyscapers compared to five story brick buildings, or stone roads compared to one of today's busy highways, which is more apparent?
     
  25. Oct 28, 2005 #24
    This brings me back to my initial point, aliens might not even want to colonize the galaxy. For all we know they may have a utopia on their home world and be just content with what they have.
     
  26. Oct 28, 2005 #25
    Entropy is correct, on my view. Despite the invention of transistors and other space-saving and energy saving devices, our demand for energy just keeps increasing. Consider what future, human, basic ecological niches, or as I prefer, adaptive zones, will be like. Think about what is common to most and perhaps all “new” adaptive zones: the presence of unexploited free energy (i.e., energy available to perform work). Consider the transition from water to land. Plants originated in the oceans, but there was all this unexploited solar energy falling onto the continents, creating an opportunity for land plants to evolve. Once land plants became established, this in turn created an opportunity for land-based herbivores, that in turn created an opportunity for land-based predators.


    Arguably, the human species has already entered three new adaptive zones since it left the jungle for the savanna. First, humans learned how to make stone tools and to control fire. This allowed them to hunt big game, and to process hides into clothes and shelters, allowing the colonization of colder climates, and fire expanded the range of foods humans could eat. The capacity to gather more free energy took another quantum leap when humans mastered agriculture and tamed wild beasts of burden. The third quantum leap in our capacity to gather free energy occurred with the advent of the industrial revolution. Thus, physicist Michio Kaku has argued that the future stages of human civilization will be marked by ever increasing capacity to gather free energy and channel it to our ends, regardless of the actual details of human evolution. That is, regardless of whether humans in the future remain pretty much the same as they are now, or genetically engineer themselves to have 500 IQ’s and 1,000 year life spans, or whether we turn into human/machine cyborgs, or whether we are replaced entirely by inorganic, artificially intelligent robots, we can be sure that the future adaptive zones that humans or their descendants will occupy (assuming we survive long enough) will involve quantum leaps in our ability to gather free energy.

    According to Kaku, we are now in what he calls a Type 0 civilization. A type 1 civilization will be able to capture the free energy of an entire planet, and will have mastered the interplanetary environment. A type 2 civilization will be able to gather the free energy of entire solar systems, allowing the colonization of nearby star systems. And finally, a type 3 civilization will be capable of roaming entire galaxies. A type 1 civilization would be able to survive calamities natural or man-made limited to the Earth itself, but would still be vulnerable to nearby supernovae and gamma ray bursts, the impending collision with the Andromeda galaxy in 4 billion years, and the death of the Sun itself. Type 2 civilizations would have more survivability, and a type 3 civilization would be for practical purposes immortal—until, that is, the entire universe runs out of free energy.

    Granted, we humans have our dark side, and we may cause our own extinction. On the bright side, it should be noted that human evolution seems to be accelerating. After 100,000 years of stone-age technology, it took only 10,000 years to reach the industrial revolution that began 200 years ago. Therefore, we can predict that humans will reach full type 1 status within the next 800 years or less. Indeed, considering that humans already co-opt 40% of Earth’s net primary productivity, that we have sent men to the Moon and probes to every planet except Pluto, and that we could—if we had the political will—manage the Earth’s atmosphere to maintain any desirable, global, average temperature, it would seem that we are already half-way to type 1 status. Michio Kaku himself has suggested that we will achieve type 1 status within a century—as long as we can stave off the terrorists who would have us return to a type -1 civilization.
     
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