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Where did life come from?

  1. Jul 1, 2008 #1
    Where did "life" come from?

    There is something about this "big bang" theory that makes me not to accept it at all and that's: Life. Physicists have all tried to put together their observations and I mean observations only to come up with this big bag theory, but at the same time there exist animate and inanimate, both made out of atoms and molecules. So far so good, makes sense, but my question is: Is animate's structure and existence exactly the same as the inanimate's? How is it possible that life = the initial micro organism from which everything evolved including us humans- EVER existed within that big bang tiny tiny spot under infinite temperatures and pressures? These are the reasons I have that makes me believe that the "big bang" theory is NOT correct and something else must have existed/happened in the distant past as 'life phenomenon' does not fit into that theory. What do you think?
     
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  3. Jul 1, 2008 #2
    Re: Where did "life" come from?

    Life is composed of the same star-stuff as the rest of the universe. The big bang was far too hot for matter to exist in the forms we commonly see it. It took a long time for the heavy elements that are required for life on Earth to be created.

    But ultimately, everything in the known universe is made up of the same materials, materials which may have metamorphosed since the big bang, but were ultimately derived from it.
     
  4. Jul 1, 2008 #3

    Kurdt

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    Re: Where did "life" come from?

    Big Bang theory doesn't attempt to answer the question of where life came from. It merely explains very well the observations we make today about the universe. I don't know why you think there were any micro-organisms around at the time of the big bang. :confused:.
     
  5. Jul 1, 2008 #4
    Re: Where did "life" come from?

    I think this question would be more appropriately handled in the chemistry/biology section of this forum.
     
  6. Jul 1, 2008 #5
    Re: Where did "life" come from?

    "Big Bang theory doesn't attempt to answer the question of where life came from.."

    Well it should. Because it says everything came from that tiny tiny tiny dot thing. and everything means EVERYTHING. I don't intend to mix the role of "God" or anything supernatural in the big bang but the question of life's origins still persists??? If life's initial form could have withstood or come from the same big bang, then it should be proved if life is capable of withstanding that infinite temperature and pressure to still live on and evolve billions of years later...any comments now?
     
  7. Jul 1, 2008 #6

    Moonbear

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    Re: Where did "life" come from?

    No, it shouldn't, and doesn't. Life came along much later after things had changed quite a lot from the original formation of the universe. The Big Bang theory only addresses how the universe started, not how things progressed once the universe got its start. It's somewhat the way Evolutionary Theory only addresses how things have evolved AFTER life started, and also doesn't address how that life actually came to exist. Abiogenesis (the formation of life where none existed before) is still poorly explained by science. There are theories around about it, but strong evidence is lacking.
     
  8. Jul 1, 2008 #7

    jim mcnamara

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    Re: Where did "life" come from?

    You have conflicting assumptions. Life is made from molecules. Life does not come in some pre-existing form. The molecules have to exist first, without life around to use them.

    You are taking 'everything' far too literally. The big bang explains the origin of matter and the universe. Life evolved here on Earth billions of years after the big bang. Using the matter left over from stellar explosions - supernovas. That where the elements with atomic numbers higher than iron come from - gold nickel selenium, etc. Some of these higher numbered elements are part of living systems.
     
  9. Jul 1, 2008 #8
    Re: Where did "life" come from?

    I might be oversimplifying - but atoms make up the universe, molecules are a collection of atoms in a neutral state, life as we know it is made up of systems of molecules.

    Life stems from atoms - which came in to existence with the big bang, no?
     
  10. Jul 1, 2008 #9

    nicksauce

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    Re: Where did "life" come from?

    This is like saying that you don't accept Freud's theories of psychology because they don't explain how airplanes fly. One has NOTHING to do with the other. Theories cannot be criticized for not explaining things that they don't try to explain or that aren't in their scope. There is plenty of research in trying to figure out the origin of life, but it is completely separate from big bang cosmology.
     
  11. Jul 1, 2008 #10

    Integral

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    Re: Where did "life" come from?

    Yep! You are oversimplifing. The BB examines how the atoms came to be. The period covered by the BB ends when the universe as we know it is in place. Life formed long after that.
     
  12. Jul 1, 2008 #11
    Re: Where did "life" come from?

    Yes and no. Yes, atoms come from material originating from the big bang, but no in the sense that it took some time for the material that comprises the observable universe to cool to the point where atoms could coalesce. In the stage prior to the creation of atoms, there should have been some kind of expanding soup comprised of quarks, leptons, and energy. Once they expanded far enough that they could cool, atoms would have been formed.
     
  13. Jul 2, 2008 #12
    Re: Where did "life" come from?

    Ah many thanks for the clarifications. So then the question is - what caused these atoms to coalesce as they do?

    Is it possible that it is also happening somewhere else in the universe? Or were these conditions a one time special thing?
     
  14. Jul 2, 2008 #13
    Re: Where did "life" come from?

    When particles' energy levels are high enough, then the electrical or nuclear bonds tend to no longer hold them together. If you heat a gas, eventually the electrons have so much energy that they break loose from the electromagnetic force of the nucleus and the substance becomes a plasma. If you heat the plasma up it could break down further and eventually become a soup of quarks and leptons, as even the strong nuclear force would not e enough to hold the atoms together.

    Essentially, during the early stages of the big bang, the matter produced by the big bang was so close together and so energetic that the strong nuclear force could not have pulled the subatomic particles into atoms. As the matter spread apart and cooled, the strong nuclear force would have started pulling together subatomic particles into larger particles such as protons and neutrons, and eventually atoms.
     
  15. Jul 2, 2008 #14
    Re: Where did "life" come from?

    (side question: is this how the LHC is planning to work? Not by super heating, but by pretty much crushing two atoms together and, I assume THIS is what the recreating of the events of the big bang would be?)

    Specifically, however, I was wondering what caused the atoms to come together to form molecules that function as they do? I have very little Physics, and no biology education, so I'm just kinda exploring realms I probably have no business in yet - but I am curious. Atoms all by themselves seemingly have no "function" persay, but the combination of them in to molecules almost kind of give them one, but its not until they start forming cells that they have some sort of active "function," i.e. they are reproducing and doin' the stuff that living things do. I'm just curious at what point does a collection of functionless pieces become something that IS functioning? I assume it's like my computer - In pieces its useless, just a collection of nice looking junk - together, and with a flow of electricity it is a wonderful device.
     
  16. Jul 2, 2008 #15
    Re: Where did "life" come from?

    What causes atoms to come together is a matter of chemistry. Chemical bonds are made, chemical bonds are broken, molecules interact, other molecules interact.

    Ascribing a putative purpose to some entities and not to others in biological systems is a tricky one. Ethylene is just two carbon atoms and four hydrogen atoms, but is an important plant hormone. Complexity is a matter of perspective - there are well-known oscillating chemical reactions that can be induced by light and can generate patterns. But it's just a mixture of rather typical laboratory chemicals.

    This is the crux of much research being done in abiogenesis. There are plenty of ideas being bandied about on a variety of issues involved in abiogenesis.
     
  17. Jul 2, 2008 #16

    Andy Resnick

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    Re: Where did "life" come from?

    There is no scientific definition of what constitutes 'living matter' as distinct from 'nonliving matter'. Until that is done (and this should be a priority), there is no way to answer the OP.
     
  18. Jul 2, 2008 #17
    Re: Where did "life" come from?

    I've read that comets could have played an important part. Comets contain a lot of organic materials. Suppose some comet is kicked out from the Oort cloud. It then approaches the Sun, heats up a bit and then moves away from the Sun and cools down again. When the comet is closest to the sun, it is still very cold inside, but hot enough for some chemical reactions to start to take place.

    These chemical reactions are very different than what you can get in a test tube on Earth. In the comet due to the low temperatures, a molecule will react with whatever molecule happens to be sitting next to it. After many orbits around the Sun, the comet's orbit changes and it spends a longer time closer to the Sun. The temperature rises and then many molecules that have been cooked up decay. Some molecules that have been formed will be very stable. The intermediary steps that led to the formation of these stable molecules may well have involved molecules that would be unstable at the current higher temperature of the comet.

    These more stable molecules can now start to react with molecules that are a bit further away due to the higher temperatures, forming more complex molecules. As the orbit of the comet's orbit is perturbed more and the comet spends more time closer to the Sun, these more complex molcules are again selected for stability.

    Since closer to the surface of the comet it is much warmer than in the deeper parts of the comet, the different phases of this process are going on at the same time.

    Suppose that the comet crashes into the Earth at a very oblique angle. Then the contents of the comet can survive the collision. Some of the complex molecules that have been cooked up in the comet will be able to survive the environment on Earth.
     
  19. Jul 2, 2008 #18
    Re: Where did "life" come from?

    Keep in mind that before you can even have the chemical interactions that form molecular compounds, you need to have different types of atoms. In the beginning there where would only have been hydrogen atoms. You need stars to form and for those stars to go supernova in order to form the heavier elements (carbon, nitrogen, oxygen, etc.) that life would require.
     
  20. Jul 2, 2008 #19

    George Jones

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    Re: Where did "life" come from?

    Comet stuff used to be considered "out there", but this view has gained a least some respectability when combined with other approaches. Here is somewhat dated National Geographic news article about a NASA project. I am not sure of its present status.
     
  21. Jul 2, 2008 #20

    Andy Resnick

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    Re: Where did "life" come from?

    None of these comments address the important difference between organic molecules (i.e. containing carbon, maybe an amine group) and catalytic or replication function. A lump of glucose will sit there. A lump of RNA will perform a specific function, and can also replicate.

    The origin of organic molecules is not that interesting- immense clouds of orgainic compounds are out there. Glycine- an amino acid- has been found in space. Far more interesting (IMO) is the origin of replicating molecules (i.e. RNA). Nucleic acids have not been detected in space, AFAIK.
     
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