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What is the single most important thing for life to exist in the universe?

  1. Mar 4, 2010 #1
    I know a lot of people say water or carbon and some people even say fusion or gravity. I think these are just the building blocks we happen to find in our universe but I think life could exist without any of those things as long as the laws of physics of any particular universe allow for something like those things to exist. For me at least, it seems that nothing is the most important thing. Life really could not exist without a lot of vacuum in between the other stuff. We see this trend everywhere we look in our universe. The stuff between the stars and planets is mostly vacuum and even on the microscopic level most of the inside of atoms is vacuum. It would be impossible for life to exist in the instant after the big bang because there was so little vacuum that things were really hot. Even when our planet formed life could not exist until most of the asteroids were cleared up. It doesn't matter what sort of physical laws you have in your universe, a vacuum is always a vacuum (more or less once you start looking closely). So any universe that can harbor life must have a lot of nothing.

    So what do you guys think, what is the most important thing for life?
  2. jcsd
  3. Mar 4, 2010 #2
    Hi Superpaul3000,
    ok im going to have a stab at this one, life couldnt exist if one of the fundamental properties of the universe and everything in it is that it has a tendency to get more and more complex with time. systems tend to self organise into ever more complex systems the reason for that? i wouldnt have a clue!
    Last edited: Mar 4, 2010
  4. Mar 4, 2010 #3
    You have to understand the paradox of the universe. The universe can only exist if there are sentient beings (consciousness) able to observe it. If there are no sentient beings, then the universe exists as a wave, without any form or structure. Only after sentient beings observe the universe does the wave collapse into the beautiful firmament of stars, planets, galaxies, quasars, etc. Thus, the single most important thing for life to exist is a universe that provides the right quantum laws that allow for sentient beings to evolve. That is, the gravitation strength is this and the strong force is that and the weak force is this and the electromagnetic force is that. If any of the four forces deviate by a slight bit, then the conditions of the quantum laws will not be correct for life to exist. It is the precise tuning of our laws of quantum mechanics that is the most important factor to create sentient life.

    There may be parallel universes that exists as only a wave function because those universes did not provide the correct quantum laws for sentient beings to evolve. Those universes are dead in the sense that they are unable to form a firmament of astronomical bodies including a sun and a planet with beautiful water and sky. There is no such thing as a "barren" cold universe unless somehow we observe it through a black hole (impossible to do). Until then, its only a wave. There are probably an infinite number of universes in the form of a wave waiting for the moment that sentient beings can observe them to allow for that universe to collapse into a world of particles and matter.
    Last edited: Mar 4, 2010
  5. Mar 4, 2010 #4
    Time, simply that.
  6. Mar 5, 2010 #5
    google "fine tuning"
  7. Mar 5, 2010 #6

    the universe only exits because sentient beings are here to observe it?
    i just dont agree with that statment i dont think the universe needs sentient beings to exist, if that statment was true then how did the universe exist before planets were formed?
    the universe begun before any sentient beings evolved and will exist long after sentient beings have died out there just wont be anyone to observe it.
    if what your saying is true magnusrobot12 then i must be missing somthing!
  8. Mar 5, 2010 #7
    I started a new thread on this paradox. No worries Robo, I have a problem with the premise too. Dmitry is helping me through it with logic and guidance, not with sarcasm. I didnt create the paradox; it exits by virtue of other ideas and the paradox has already led me to learn about Shroedinger's cat and Decoherence theory. Isn't that why we are here?
  9. Mar 5, 2010 #8
    Can we please stay on topic, I know interpretations of QM are interesting but thats for another post...
  10. Mar 5, 2010 #9
    Hi magnusrobot12, i hope you dont think im being disrespectfull or sarcastic? If so im sorry. that was most certainly not my intention. I think this is an interesting subject. Cheers. Rob060870
    Last edited: Mar 5, 2010
  11. Mar 5, 2010 #10
    seriously superpaul, the answer to your question is the fine tuning of the laws of quantum mechanics is the most important thing for life to evolve.

    But if you want a biological answer, then it would have to be that a planet is revolving at precisely the right distance from a star that is precisely the right size so that the right amount of energy along with planetary energy provides the resources for protocells to form in liquid water upon which the protocells develop the ability to self-replicate probably in the form of RNA nucleotides. I like the idea that the building blocks of life were actually being carried by asteroids so that they showered the earth with amino acid and nucleotides and then there was self-assembly probably on clay surfaces in shallow liquid water that were able to form a lipid membrane to form these protocells. From there on, it was a free for all, with all these building blocks everywhere, cells were able to internalize them and replicate until all the building blocks were gone and then the cells had to get their resources from other cells and that is when they started engulfing each other and the survival of the fitess began. however, there was a subset of cells that, after engulfing a smaller cell, did not destroy the engulfed cell to steal its nuceotides and amino acids, instead it allowed the engulfed cell to reside in them and that engulfed cell developed the ability to convert solar energy to molecular energy and they were able to build their own source of energy and did not have to hunt down other cells to steal their building blocks. This the evolution of chloroplasts. Since photosynthesis was a great invention, more cells starting doing it and before you know it O2 dominated the atmosphere and that caused mass extinction except for those clever cells that, when they engulfed smaller cells, they too did not destroy the engulfed cell but rather let them live and those engulfed cells were able to take O2 and evolve an electron transport chain thereby making more energy than ever before. This is the evolution of mitochondria. Then these unicellular formed colonies that became multicellular organisms and the rest is history...

    No worries mate. Thanks
    Last edited: Mar 5, 2010
  12. Mar 5, 2010 #11


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    Matter would seem to be the most singularly important thing. From matter comes energy (fusion), chemical processes, gravity. Of course, there are different forms of matter.
  13. Mar 6, 2010 #12
    There is no single thing, but many. Remove the element carbon, for instance, and there would be no level of self similar replication we would extrapolate to the category we call 'life.'
  14. Mar 6, 2010 #13
    Well, er, reproduction...:blushing:
  15. Mar 6, 2010 #14
    It depends on how you define life. It my opinion life has a beginning and an end and in between those end points it consumes resources, create waste products, produce offsprings.

    Therefore, as stated before the single most important thing for life to exist is time.
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