Chance of life on other planets

Discussion in 'Astronomy, Exobiology, & Cosmology' started by James R, Sep 4, 2010.

  1. John99 Banned Banned

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  3. Randwolf Ignorance killed the cat Valued Senior Member

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    Check this out - see if you can find any similarity. (Apologies for being unable to find any simpler examples)


    http://mathforum.org/dr.math/faq/faq.prob.intro.html

    Comprende?
     
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  5. John99 Banned Banned

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    If i tell you there may or may not be a peanut under a cup then what is the percentage that there may (will) be a peanut under the cup? I didnt say what kind of peanut, just a peanut.
     
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  7. Randwolf Ignorance killed the cat Valued Senior Member

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    Irrelevant - totally different kettle of fish as to stats. But I think, ummmm..... the answer is, is,.... 50%? However, this has nothing to do with the OP.


    John, investigate "inferential statistics".

    Definition:
    Here is a site for some basic reading:
    http://psychology.ucdavis.edu/sommerb/sommerdemo/stat_inf/intro.htm



    Edit (simpler explanation):
     
    Last edited: Feb 21, 2011
  8. John99 Banned Banned

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    Come on, Rand. Who are you trying to convince?
     
  9. SciWriter Valued Senior Member

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    The Implications of Infinity and Eternity…

    It is very likely that there are other Earths out there even exactly the same as ours. As we will see, the universe retains its own history and future.

    The All, meaning Totality, as we know, cannot be bounded (or it wouldn’t be the All), and so its extent must be infinite. Nor can it have a beginning, for then, again, it wouldn’t be the All, and so it must be eternal.

    In an infinite eternal place, which I will call the universe or the cosmos, every possible combination of matter and energy (unstructured matter) exists, not only right now, even many times over (due to infinity), but ever will and did, even many more times over (due to eternity). Since the Earth (and everything known) is a part of ‘possible’, since it is here, there’s no problem with that use of the word ‘possible’.

    It’s only those things that we don’t know are possible that we can’t say for sure. We’ll have to wait for better computers to figure it out, a daunting task since even a state of one change of one atom requires a precursor form and a series of prior events cascading backwards through infinite time and across infinite space.

    However, there is still every possible combination of matter and energy; it’s just the resolution that remains unknown. Think of morphing objects together; the resolution is like how many intermediate stages there are (possibly infinite, but who knows).

    I am calling this notion ‘supercontinuity’. It says that any object known to us, whether a galaxy, planet, person, or whatever has a prodigious number number of very similar examples in space somewhere, varying along every possible parameter. This supercontinuity must be true by virtue of the universe’s permutational variability. The only question is what is its resolution: how closely can these (separated) instances of any given type of object resemble each other?

    For example, even on Earth, between human races, the percentage of DNA separation is less than .1 percent (2% between chimps and humans). There is even a web site where one can look up their so-called ‘doubles’ on Earth. Identical twins have identical DNA, but differing experiences (so we are not yet at the stage of identicality). To be exactly the same, they would have to have the same molecules and quantum states.

    But, heck, there is all of space and all of time; thus, it is very likely, even certain, that at least some intermediate states of a certain resolution exist somewhere at this very moment, and always did and will at any given time. If there is not exactly another Earth, surely there could be one whose only minor difference was one unnoticeable at the atomic level.

    So it is that every loved one we have ever lost is alive and well somewhere (as an exact duplicate). Of course, they may be separated from us by a humongous distance, but are indisputably alive right now; this instant, as they ever were and will be.

    Such it is, in this way, that moments are never lost in the infinite eternal universe, for every touchdown pass and first footstep on the moon is still ever happening somewhere. Somewhere, too, dinosaurs roam distant lands just like those of Earth. So, the universe contains its own indelible history and future. All moments of every object’s history exist permanently in space, separated by near-infinite distances (if not infinite).

    Consider this supercontinuity to be your secular ‘afterlives’, some of which are identical and some for which the narrative may differ slightly. Either way will do, for any narrative will do, but if it is the same, you wouldn’t remember it.
     
  10. Randwolf Ignorance killed the cat Valued Senior Member

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    Someone who is apparently incapable of doing 10th grade school work.

    P.S. Please note the edit to my last post. The concept can not be explained in any clearer fashion.
     
  11. John99 Banned Banned

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    Were talking about the OP, where are you getting all this "black marble, white marble, red marble" crap from? No one mentioned these things but you. Nothing at all to do with the OP. You are hallucinating.
     
  12. John99 Banned Banned

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    I suggest you re-read the OP, Rand.
     
  13. Randwolf Ignorance killed the cat Valued Senior Member

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    OK - I would give 80% odds that your name is all over it. Furthermore, the truth can not be properly classified as an "insult".

    I was going off memory in my first reply to you, albeit an intrusion in the discussion between you and Dywydder. I then spent time hunting references for you. Obviously you are either so arrogant or so uninterested in learning that you refuse to even entertain the idea that there is a concept that you are currently deficient in. In retrospect, I should have stayed out of it. Math / stats is obviously not your forte. My apologies...

    Anyway, I'm tiring of this off topic crap, because I'm actually interested in the OP subject. Goodbye, and thanks for all the fish.


    Back on topic...

    Astounding (to me) the number of potential life-bearing planets discovered by the Kepler mission, especially in such a short period of time.
     
  14. orcot Valued Senior Member

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    Let's hope it's enough to draw on a larger budget. All apart of the James Webb Space Telescope had their budget cut over the years it would be nice to see at least some of them reinstated in the least I hope the result put the ATLAST telescope safe but then again it's allready a NASA flagschip mission for the 2025-2035 time period.
     
  15. NMSquirrel OCD ADHD THC IMO UR12 Valued Senior Member

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    it helps when they know what to look for..
     
  16. orcot Valued Senior Member

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    Not really, the kepler space telescope watches 145 000 stars at the same time. Apart from all being main sequence stars kepler favors M type dwarfs because of the short rotations (over 80% of the discovered planets have rotations of less then 40 days mercurys rotation for comparison takes 88 days).


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  17. NMSquirrel OCD ADHD THC IMO UR12 Valued Senior Member

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    interesting that the bulk of the planets are 1-4 x earth mass..
     
  18. orcot Valued Senior Member

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    yep the universe is dominated by neptune class planets apparently
     
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Possibly, but hard to be sure as our detection processes favor the detection of larger planets (They make more Doppler detectable wabbel of thier sun and reflect more light at any distance from their sun than a smaller one would.) Note also that the smaller ones tend to be found nearer to their sun - that does not mean there are not more at greater separations from their sun.

    Very large planets will not be found near their sun as gravity gradients would convert them into smaller planets.
     
  20. keith1 Guest

    Good reply, but expected, and glad to see you are thinking.
    Expected, but I thought it out further before venturing the post, and preceded with the the following in mind:

    --The American Indians came in waves to the new world, some by sea and some by land-bridge from Asia/Siberia. Tribal differences.

    --Deep snow cultures are the exception, and all very peaceful. Eskimos an example.

    --To explore space a culture must:
    ----1) have the intelligence to look up and ponder.
    ----2) develop a propellant:
    -------a) Asians played with rocket fuel as an entertainment spectacle.
    -------b) Advanced to scaring their enemy's with the noise and lights (war)
    -------c) Next, tied to arrows, to deliver projectile (war)
    ----3) Develop rockets
    -------a) Cannon/Dynamite (war)
    -------b) German V2 rocket (war)
    -------Sputnik (cold war)

    Achieving extreme environments like Everest, Sea Trenches, and Polar Regions were low-tech benchmarks, not needing the complex systems required in leaving a gravity well (zero gravity orbit).
     
    Last edited by a moderator: Feb 22, 2011
  21. orcot Valued Senior Member

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    actually it was as straight forward as most of the rest of the world.

    Yes the vikings were notoriously know for spreading the love over europe

    my dog does that all the time
    okay we won't agree on anything here.
    inventing stuff yust isn't enough the greeks 2000 years ago invented the steam engine yet it took almost 1800 years for the industrial revolution to happen. You said that conceuring everest and visiting the deap see trenches and polar caps are low tech and perhaps they are compared with todays technology but they needed the same support so necesairy today for starting a large project.
     
  22. keith1 Guest

    Yes, and the Europeans met them with like cultural understanding.

    Funny your dog looks at the stars, and a dog was the first "earther" into space.


    Can one necessarily equate steam engines, mass production, and other culture-boosting "soft techs", a result of warrior-driven motives (the techs responsible for escaping a gravity well)? I think not.
     
  23. D H Some other guy Valued Senior Member

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    Dinosaurs were the dominant species for 160 million years. Primates have been a small niche set of species for 65 million years. Moreover, some primates are intelligent, some rather stupid. A better comparison would be the great apes, which have only been around for 15 to 20 million years. With the exception of one branch, the great apes have lived rather precariously in narrow environmental niches. That one exception, our branch, has only been around for a couple of million years. How is that "high resiliency"?

    There are too many unknowns regarding the conditions necessary for communicative life to arise and regarding the probabilities of such life arising if the conditions are right. Note: By "communicative life" I mean life capable of escaping its planet / communicating with other communicative life.

    We don't know what makes a planet habitable, or how many stars have habitable planets. That a planet lies in the star's habitable zone is one condition, and that is all that Kepler can see. Some other conditions conjectured to factor in to whether a planet is habitable include:
    • Rotation rate. Too slow a rotation rate and the day/night temperature extremes may be too much for life to handle. We don't know what the "right" rotation rate is. All we can do is extrapolate from a sample size of one.
    • Water. Water is essential for life as we know it. We don't know yet from whence Earth's water arose (but consensus is moving toward outgassing), and we certainly don't know whether those candidate planets observed by Kepler have water.
    • Atmosphere. Even though Venus is considerably further from the Sun than is Mercury, Venus is the hottest planet in the solar system thanks to its atmosphere. Mars has an extremely tenuous atmosphere. If life does exist on Mars it is probably in the form of very simple extremophiles. Both Venus and Mars are inhospitable to complex life, yet both are in (or have been in) the Sun's habitable zone.
    • Magnetic field. The Earth has one, Venus and Mars essentially do not.
    • Plate tectonics. The Earth undergoes plate tectonics while once again Venus and Mars do not.
    That is a partial list, and we do not know how those conditions affect habitability. The best answer right now is that we don't know -- but it is a question worth investigating. Kepler has made the first step in giving us targets to look at.

    That is just habitability. Given that life formed rather quickly after the Earth cooled to the stage where it was habitable, it is reasonable to assume that life probably will arise if the planet is habitable. However, that is once again extrapolating from a sample size of one.

    We're still only a small ways down the path to communicative life. Life on Earth was extremely primitive for most of the history of the Earth. That suggests (extrapolating from a sample size of one) that complex life is far from a certainty. Note that the probability of the origin of complex life is not a part of the Drake equation.

    We're still a long ways from communicative life. Near-intelligent life, such as primates, has to arise first. The next step is the formation of an intelligent life form (a species that later can be construed as constituting communicative life as defined above). While near-intelligence arose multiple times (parrots, squid, toothed whales, mammalian carnivores, and primates), intelligence arose but once. The probabilities that near-intelligent and intelligent life forms will arise is once again not a part of the Drake equation.

    A long time passed between the formation of the Earth and the first hominid. In this time, life has been nearly wiped out multiple times. Was the Earth lucky or unlucky with respect to these disasters? The answer is we don't know. The probability of life surviving long enough to form an intelligent species is once again not a part of the Drake equation.

    Let's assume an intelligent life form does arise on some other planet. We still aren't at the stage where that intelligent life form becomes communicative life. That requires this intelligent life form advancing beyond the stone knives and bear skins stage. Our Earth has an abundance of metals that let us get past that stage and an abundance of hydrocarbons that let us get past Medieval technology. Could an intelligent life form become a communicative species on a planet that is metal-poor or didn't have the equivalent of a Carboniferous era? We don't know, but once again this question is not a part of the Drake equation.


    Bottom line: There is a lot that the Drake equation does not take into account, and those additional factors might result in communicative life being very, very rare. The Drake equation is not science. It is unscientific, unfalsifiable guessing.
     

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