Fermi paradox

Discussion in 'Astronomy, Exobiology, & Cosmology' started by madanthonywayne, Jun 5, 2007.

  1. orcot Valued Senior Member

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    descibe wormholes do they contain mass, virtual or real?
    anyway skipping the alphabet to go from a to z sounds nice
     
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  3. dixonmassey Valued Senior Member

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    Why don't you all discuss a good old fairtale, bible verse or some sci-fi book instead? Possible extraterrestial life on 70 sextillion planetary systems seems like totally out of our reach to verify or argue about using anything but faith.
     
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  5. BenTheMan Dr. of Physics, Prof. of Love Valued Senior Member

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    orcot---I couldn't tell you. There is serious research being done into the subject, though.

    dixon---do you troll the religion forum with the same sorts of posts?
     
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  7. dixonmassey Valued Senior Member

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    Just don't forget to let us all know after you'll solve misteries of the extraterrestial life

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  8. BenTheMan Dr. of Physics, Prof. of Love Valued Senior Member

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    will do.
     
  9. pinkiss Registered Senior Member

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    short joke for yous

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    In world war 3 humans will fight with nuclear bombs ,in WW4 humans will fight with sticks and stones

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  10. MarcAC Curious Registered Senior Member

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    Haaaaaaaaa... hah hah!

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  11. MarcAC Curious Registered Senior Member

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    Correction: "do you hog..," not "do you troll."

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    This thread is really hitting the funny bone...

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  12. Fraggle Rocker Staff Member

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    I think that's a very sensible answer. I don't see that we have enough data to perform the estimating process.
    I don't call it trolling for a person to come to one of the science subforums and remind us that applying the scientific method to the tiny amount of observations we have on this subject is really stretching it. It probably would qualify as trolling on the religion subforum because those people by definition don't use the scientific method and the criticism would be inappropriate. However I personally would ignore the offense.

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    That said, I still think this discussion is worthwhile. Conjectures are more or less clearly labeled. A lot of science has been reviewed here, much of which is surely new and interesting to some of our readers.

    "Faith" is a type of hope, and scientists are allowed to be hopeful as long as we tell the folks that that's what's going on.
     
  13. madanthonywayne Morning in America Registered Senior Member

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    Gravity waves are strictly theoretical, right?
    You'd definitely need some kind of "shield" if traveling in real space. In a wormhole or higher dimension, who knows? Perhaps whatever device allows you to survive wormhole or higher dimension travel might also provide some protection from hypervelocity specs of dust.
     
  14. kaneda Actual Cynic Registered Senior Member

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    Look at what happened in the past to the groups of people contacted by the "civilised world". The red indians, the aboriginies, many tribes worldwide, and so on. It wrecked their socieities. Imagine if aliens landed tomorrow and gave us the secret of curing all diseases and technology that would put 98% of all people out of work and bring closer a population doomsday. Imagine proof that all religions are wrong, that some scientific beliefs are wrong as are various other beliefs and finding out that there are billions of other races in the universe more advanced than Mankind. And being read the riot etc, that since Mankind is such a savage group, we will not be allowed out of our solar system till we are civilised. But savagery is hardwired into our DNA.

    It may be a deliberate act that we are not contacted and we will only be contacted when we develop star travel and so will inevitably meet aliens sooner or later.
     
  15. madanthonywayne Morning in America Registered Senior Member

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    Robert Sawyer wrote a book (I think called calculating God) in which aliens landed at a museum and immediately asked to speak with an athropologist. The aliens were on an interstellar quest to prove the existance of God and determine his purpose in creating the universe.
    I think that's idea is incorrect. So far on earth we've seen no evidence that advances in technology mean decreased violence. Quite the contrary. I'd venture to say that aliens, however advanced, will be just as violent as us. Perhaps even worse.

    A mitigating factor might be that more violent species would perhaps be more prone to self destruction. But, on the other hand, if ten species managed to advance to the level of interstellar travel and all but one had become complete pacifists; who do you think would come out on top? Survival of the fittest extends doesn't apply only to earth.

    Furthermore, war seems to be very effective in forcing technology to advance quickly. It may well be that all high tech intelligent species are prone to violence. The peaceful species being happy just living on their farms and never needing to invent guns, or cannons, or rockets, or spaceships.
    Ah, the Prime Directive, eh? Could be. Or, as the OP suggests, it could be all the aliens are tooling around their planets on horses (or whatever alien analog they have for horses).
     
    Last edited: Feb 11, 2008
  16. Laika Space Bitch Registered Senior Member

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    I don't think that the historical situations you've cited are entirely relevant. In those cases, I understand that the spread of disease was at least as large a factor as culture shock and the deployment of advanced technologies. Even if contact with ET was face to face, the chances that their diseases will be compatible with our biochemistries is vanishingly small.
     
  17. madanthonywayne Morning in America Registered Senior Member

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    That's an excellent point. It's hard for a culture to survive when most of its members are dead.

    An example of the sort of first contact you envision was portrayed in a book I read in which the aliens were arch capitalists, mainly concerned with expanding into new markets.

    The main character was a venture capitalist who had been about to release a new product that he'd poured his entire fortune into. It was an amazing technical breakthru. The aliens had a convention and were offering a product light years ahead of his for a fraction of the price. He was ruined.

    Ultimately, he realized that the earth was now "the third world". So he decided to take advantage of the low labor costs on earth and produce some trinkets, he'd then use the revenue from the sale of the trinkets to "modernize" earth (buy alien tech).

    I can't remember the title, but it certainly offered a unique take on first contact.
     
  18. nanode Registered Member

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    I agree, if we were to come into contact with life that developed independently from our own evolutionary path I would like to think they would have an alternative biochemistry. Carbon based life might just be a niche that occurred here on Earth.
    Hell, we could already be interacting with an omnipresent life force that inhabits the universe but evades our perception and sits back observing our crazy selves.
     
  19. BenTheMan Dr. of Physics, Prof. of Love Valued Senior Member

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    Why does everybody think this?

    No. Gravity Waves are a very well known phenomenon.
     
  20. fadingCaptain are you a robot? Valued Senior Member

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    2 things:
    -Distance scales in the universe are far beyond our ability to comprehend. When we talk about something being light years away, it is beyond us to really grasp just how far that is. Given the apparent universal speed limit, it is probable that these distances are just too great. If that weren't the case, there has been ample time for a civilization to make its presense known.

    -There is always the possibility that we are inherently limited in our scope. Concepts like "Life" and "intelligence" could be very different under other conditions. Would something so different communicate with electromagnetic radiation? Would we know it if we saw it and vice-versa?
     
  21. Fraggle Rocker Staff Member

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    This is a popular topic and a new thread is started about every six months, covering the same material over again. IIRC, the conclusion of the last thread was that SETI is useless beyond a very small range, something like 100LY.

    The universe could be packed with advanced civilizations who will never know of each other's existence.
     
  22. BenTheMan Dr. of Physics, Prof. of Love Valued Senior Member

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    Well, here goes. I have had this in the back of my mind for several months.

    Yes, I propose that electromagnetic communication is the only viable communication that one can use to convey any meaningful amount of information any significant distance.

    The basic reason is that the coupling constant for electromagnetism is small (~e^2) where e is the charge on the electron. This means it takes a very small amount of energy to excite an electromagnetic wave. This means that one can excite many electromagnetic waves very easily.

    Next, one would imagine that most intelligent life forms on small, rocky planets, a reasonable distance from an average star. There is a huge evolutionary advantage in beeing able to see, so one would assume that most intelligent life has this capability. If an organism can see, then it's visible spectrum should overlap with the most intense radiation from the sun. It is actually how beautifully our visibile range overlays the sun's radiation:
    http://en.wikipedia.org/wiki/Image:Solar_Spectrum.png

    Now, a few things. To excite many photons for a small amount of energy, one wants radiation in the IR end of the spectrum. This also ensures that you can propogate a long way with little chance of interacting with outside stuff---i.e. you can send a message without losing as much of it. For example, have you noticed how many cell phone towers are around? Cell phones use radiation at the UV end of the spectrum, and the UV radiation can be absorbed by the atmosphere, which is why cell phone reception deteriorates the further you are from a tower. And it ensures that you aren't sending signals in the visible range, (which would be a disaster!)

    So, given all of these constraints, we can look at the alternatives. Sound cannot encode as much information as a light signal, plain and simple. Further, interference from outside sources would be too big. Of the four forces we know, gravity and electromagnetism are the only ones that can propogate an infinite distance. But given that we don't understand quantum gravity as well as we understand quantum electrodynamics, it seems reasonable to expect that any outside civilization would find similar shortcomings---that is, I would claim that physics is almost universally driven by experiment.

    If anyone can think of another viable communication method---that is, one where you can store as much information and propogate it with as little energy, I would love to hear an argument.
     
    Last edited: Feb 13, 2008
  23. Walter L. Wagner Cosmic Truth Seeker Valued Senior Member

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    BenTheMan:

    Your analysis of why EM is the prefrerred coummunication channel is the same as given by many others over the past 3-4 decades at least, and is quite proper.

    However, due to the limitations of space-time [c is small and finite compared to space distances], and expecting a 'reply' to any signal, one might assume ET would choose instead to send a 'robotic mission', which could be far more complex than simply passively announcing one's existence. To me, that would seem far more reasonable than simply announcing one's presence.

    Placing a huge body of knowledge [how to make an ET body, the ET body of collected wisdom, etc.] into a small volume [and small mass] would not be difficult for ET. Accelerating that small volume [read, small mass] to 99.9c would allow it to arrive at essentially the same time at its destimantion as any EM signal that was otherwise sent. On arrival, it could decelerate by being captured gravitationally initially, and then followed by an appropriate braking mechanism.

    Such 'device' could also build intelligent beings [robots, or biorobots, etc.] at its destination. Sending billions of such devices at 99.9c would not be difficult for ET. They could survey, collect information, etc., then move on, while sending communications back to its origin.

    Of course, this is nothing new and is speculated about in numerous sci fi stories.

    Regards
     

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