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Model for a cyclic universe.

  1. Jan 3, 2012 #1
    To begin, and beleive me, it will become apparent, I have no training or education in this field. I do however find it fascinating.
    Can someone with a greater understanding please tell me if my ideas are laughable or feasable? Has anybody else proposed these ideas?
    Okay, so.....

    Beggining - Big Bang

    Electrons and protons form H2. H2 gravity and time produce stars.

    Large stars go super nova, creating heavy elements. Massive stars go hyper-nova creating black holes.

    Planets and moons acrete, stabilize orbits, and become solar systems.

    Stars form orbits around super massive black holes, creating galaxies.

    A super massive black hole attempts to merge with it's anti-matter equivalent, reducing mass and gravity instantly and dramatically, producing massive energy.

    - Big Bang
  2. jcsd
  3. Jan 3, 2012 #2
    All this isn't implausible. We really don't know how galaxies form, although current thinking is that it's top down with the super massive black hole probably forming before stars.

    Black holes aren't matter or anti-matter. If you merge two black holes, you'll get a bigger black hole. Also mass and gravity doesn't get reduced.
  4. Jan 4, 2012 #3
    Thanks for your reply. I need to study some of the learning materials on this site, and get my head around basic physics. My reasoning was basicaly that if a black hole is created by the massive pressure of a star compressing it's collapsed core to a point where it's gravity prevents light from escaping, wouldn't there exist a compressed core of matter? Could there be entire stars made from anti-matter in which the same thing could happen? I'm sure these are very ignorant questions, and I fully intend to study up on the subject. Thanks for your patience and your input, and happy new year.
  5. Jan 4, 2012 #4
    In my understanding indeed black holes and big bang are very much related.
  6. Jan 4, 2012 #5
    There's a singularity.

    There are strong observational limits on how much antimatter there can be. Basically if you have a mix of matter/anti-matter you'll see radiation were they mix, and we don't.

    Also the big bang isn't an explosion, and the energy that you get blowing up stars is insignificant in the grand scheme of things.
  7. Jan 4, 2012 #6
    How would you define an explosion ?

    I know super massive black holes.
    Let's assume there are even larger, gigantic black holes.
    What would be the energy released of such a black hole (if it could/woud explode) compared to the energy/mass of our universe ?
  8. Jan 4, 2012 #7
    Thanks for clearing that up. My thinking wasn't so much the explosions of the stars themselves, but more a guess at the possibility that a super massive black hole could have some sort of nucleus, that if there was an opposite version of that nucleus, there would be a vast cancelling out of mass, production of energy, and a vast, almost instant reduction in gravity.
  9. Jan 4, 2012 #8
    One thing that will help is to put numbers to things. If you think about say an ant trying to push a car, you know that won't work because you have a "feel" for how big a car is and how much force an ant can generate.

    It helps to do the same sort of calculation in astrophysics. If you can get a "feel" for how much energy a star puts out, how big a star is, you quickly figure out that stars are tiny in comparison to the universe.

    Something that helps is to take an intro astronomy course and every time someone mentions a number, you draw it on a graph, so you get a sense of how big/small, heavy/light things are. Also the movie 'powers of ten" is good for this sort of thing.
  10. Jan 4, 2012 #9
    Duly noted. Thanks for your suggestions.
  11. Jan 4, 2012 #10


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    The key difference between the big bang and an explosion is that an explosion happens in one place and the BB didn't.
  12. Jan 4, 2012 #11
    If you trace back impulse of all mass, where would this end up you think ?
  13. Jan 4, 2012 #12


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    I don't know. Is the implication of your question that you think the BB was a point event?

    EDIT: "I don't know" => the singularity => I don't know
  14. Jan 4, 2012 #13
    It doesn't need to be an infinite small point, per se.
  15. Jan 4, 2012 #14
    This mass would be everywhere, because if you trace geometric expansion backwards you just get a more dense Universe. Now if you trace back all mass from the OU it all ends up right here on Earth, however you are asking for all mass in the entire U.

    As BB expansion occurs at all points, fits in with isotropy and allows for almost exact uniformity then the answer has to be that if you trace back ALL mass, eventually it was eveywhere (as everywhere was more condensed then.)

    Hope this helps and its an interesting topic.
  16. Jan 4, 2012 #15
    If you would geometrically trace back all current motion vectors, it for sure must up in a point in our current space ?
  17. Jan 4, 2012 #16


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    nope ... you are assuming a point origin of the singularity and all evidence is that that is not the case ... it happened everywhere at once and has no center that you could project back to.

    This is cosmology 101 and is addressed on this forum with GREAT frequency.
  18. Jan 4, 2012 #17
    If you could do this for the Observable Universe, or the parts of the Universe we are causally connected with then the centre would be the Milky Way - this is the center of the Observable.

    The Universe as a whole is isotropic, isotropy precludes centers and edges, centers/edges would invalidate isotropy which we know is not the case as we can see uniformity in the CMB.

    As i stated, if you trace back ALL motion vectors, not just those in the Observable Universe, you would merely end up with a more dense Universe, there is no place in space you can point to and say the BB started there (After planck time), because "there" didnt really exist. You are trying to "place" a global geometric expansion into a pre-existing background prior to current physical laws and metrics.

    To clarify, you can point to any place in the Universe and say that the Big Bang began there and you will be correct - the Big Bang Banged everywhere at once.

    I hope this helps
  19. Jan 4, 2012 #18
    Let's assume I write a big bang simulator in software, and I use plain euclidiean 3D + time space. If I'm given all current motion vectors and trace them back where would I end up in this simple universe ?
  20. Jan 4, 2012 #19
    If you are using flat euclid space you end up with an open and flat cosmology. Therefore the mass in the U is infiite, with infinite motion vectors accordingly. If you take an infinite amount of mass/space that has expanded, and you trace it back, then you would end up with an infinite (just more dense) Universe at or near to the point of the BB.

    Either finite or infinite models DO NOT allow for any center/edges within their topology, while the balloon analogy has its limitations it seems quite relevant here.
  21. Jan 4, 2012 #20


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    please don't say point ... you KNOW what confusion this causes
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