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Hells Angels bikie in a Beijing Opera Concert

  1. Nov 12, 2013 #1
    Space is endless, I mean the 'real space' outside our universe.

    Our Universe is said to be about 13.7 billion years old but it is 150 billion years in Diameter. I don't want to get into all the specifics because it does my head in and truthfully I'm not that smart but if the big bang was to happen somewhere else in 'space' and spawn another universe what would make it different to our own universe?

    Would everything be the same? Would all the particles, atoms etc. etc. after the big bang (singularity) fly off in the same direction? Would everything be exactly the same? Does randomness and chance play a part in this?

    Is there another me writing this now or at another moment in time? Does me realizing there is multiple other me's in other universes let me change the path of destiny?

    Are some champions of string theory right in saying when two universes smash together they create another big bang and it starts all over again?

    Because of the vast distances involved in the above are these questions that may never be answered?

    I am an underground Diamond Driller, basically an uneducated labourer who is more than likely way out of his depth/comfort zone like a Hells Angels bikie who accidently finds his way into a Beijing Opera Concert.

  2. jcsd
  3. Nov 12, 2013 #2
    Come to think of it there is no such thing as randomness and chance, if you have the exact same variables the outcome should be the same, it all comes down to the singularity.
  4. Nov 12, 2013 #3


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    Hi Sharky1! Welcome to PF! :smile:
    Brane theory (see eg http://en.wikipedia.org/wiki/Brane_cosmology) imagines that our 3D universe is in a higher-dimensional "bulk".

    (There is no evidence for or against brane theory)

    If there was another universe, floating around in the "bulk", it could affect our universe, but only by gravity, since gravity is the only force that can "leak" across the "bulk".

    Gravity wouldn't affect the nature of particles (electrons quarks etc), so chemistry should be the same. The only noticeable effect should be that the gravitational constant G would be different in some parts of our universe.

    In a big bang, everything goes in every direction (and btw, only fundamental particles, not atoms … atoms come later).

    Yes, randomness and chance is what leads to "clumping together" that eventually become galaxies.
  5. Nov 13, 2013 #4
    Hi Tiny-Tim,

    Thanks for your reply, good to know someone is reading and willing to reply.

    Do you think gravity leaking across the "bulk" is why it is a weak force compared to the other 3 forces? I remember seeing that in a doco years ago called down the rabbit hole or something which I assume you are familiar with.

    I also remember reading that subatomic particles can pop in and out of existence. What are your thoughts on this? Apologies if I am asking too much as right or wrong I assume you have already been asked these questions in the past.

    If I could bother you with one more question could you point me in the right direction to find information on the "clumping together" of galaxies? With regards to randomness and chance it sounds like there must have been some kind of experiment where the catalytic variables were exactly the same to prove that randomness and chance does exist.

    Thanks again for your reply and your interest in my questions. As previously stated I am reasonably uneducated and am very happy to have someone answers my questions which others might found boring and obvious.


  6. Nov 13, 2013 #5


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    There is no such thing as space "outside" our universe that we know of.

    The big bang happened everywhere in the universe, but think I understand your question. The truth is that we have no idea. The origin of the universe is a mystery to us. All we know is that our universe was once much denser and hotter in the past and has expanded and cooled over time.

    Unknown. Randomness and chance would play a part in certain things, like which areas of the universe are more or less dense than others, but as for the fundamental laws we simply don't know.



    Maybe. I expect it's more like we may not even be able to observe alternate universes at all, even in principle, thanks to the way the laws of nature work.
  7. Nov 13, 2013 #6


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    You are referring to virtual particles, something which is dealt with in quantum theories, not cosmology. The concept is extremely confusing if you don't know much about physics, so my best advice would be to just remember that virtual particles aren't "real" particles that we can observe and measure.

    The matter in the early universe was extremely dense, and quantum fluctuations resulted in some areas of space being slightly more or less dense than others. The matter in denser areas eventually coalesced into galaxies and stars, while the less dense areas lost their matter to the denser areas and became voids. At the quantum level we truly have complete randomness, as far as we know, so it is accepted that these fluctuations would have been random in nature.
  8. Nov 14, 2013 #7


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    Hi Steve! :smile:
    That wouldn't depend on the existence of other universes in the "bulk" …

    the leaking of gravity would happen anyway.

    If there are no other universes in the "bulk", what difference is there between (a) the "bulk" existing and explaining gravity, and (b) a mathematical rule which operates entirely in our universe and which has the same effect? :wink:
    Pairs of particles (one the anti-particle of the other) certainly do pop into existence.

    Single particles don't (the single "virtual particles" in quantum field theory and feynman diagrams are only a mathematical trick which helps in certain calculations).
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