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M-theory and Chaotic inflation

  1. Dec 31, 2011 #1

    I am not currently studying, have never studied Astrophysics, so will no doubt come across as rather inadequate in trying to clarify, what my question actually is.

    Please forgive me for not using appropriate terminology, and, if this forum is not for the curious laymen in the general population, please do point me in the right direction. I was rather impatient in my need to find answers, and was hoping that this forum, and the academics on it, could shed a little light for me. Please also note, that unfortunately for you, most of what I am asking is based on much "dumbed down" information, acquired from documentaries etc...I can feel your scorn already.

    As I understand it, the actual odds of a Big Bang event are, relatively speaking 0, until you apply M-theory to the equation, to effectively increase the odds of a Big Bang event.

    Chaotic Inflation, and the idea that the universe is in fact infinite, is where i come undone. If the universe is infinite, there is no other "area" for another universe (assumed to be also infinite?) to exist, alongside, and outside, this universe, to in fact influence the movement of matter in this universe. I can go with the idea of there being levels within this one infinite "space" and having parallel "levels within it, but completely separate spaces that exist side by side exerting some sort of force or influence on each other seems strange, when trying to use the label "infinite"

    I guess the question is, if we go with the idea of other universes outside of this one, then is it not a given that the universe is not infinite, and, if the universe is infinite, is it not a given that these parallels are not actually universes as such (being that they themselves are not infinite but rather grades or levels that make up what we consider the infinite universe) and that another label would be required for these levels, instead of the word "universe".

    If this is the most incoherent, unintelligent, and completely misguided question, any of you have ever been asked, I humbly apologise for wasting your time, and ask that you please be gentle in your responses, if any at all are given.

  2. jcsd
  3. Dec 31, 2011 #2
    In particular, I have been watching BBC's Parallel Universes, and while I can accomodate the ideas, in a rather limited way, for Level 1, 2, 3 and 4 "multiverses", I cannot go with the idea put forward, that in the future, potentially, we could "ensure our survival" by "concentrating enormous energy at a single point to attain something called the Planck energy, the ultimate energy, space and time itself become unstable, little bubbles begin to form, little bubbles that are perhaps portals, gateways to another universe..." etc etc. The idea being that we can move across to another "layer" or universe in order to continue, survive our inevitable demise...

    the reason I can't follow the logic? Well, it was already stated that in these parallels, there already exists "copies" if you will of what already exists here...This is all starting to sound a bit "fringe" to me...how can we say or even begin to assume what these parallels even contain. Why is it an apparent given that these other layers contain anything like what is currently on ours? who is to say the "laws of physics" even apply in the same way, or that there are other versions of ourselves re-iterated...the math may suggest this is the case, but who is to say the math we are applying is even correct...

    If the assumption that these other layers already contain other versions of ourselves...why would we need to ensure these current version "find a way" to continue on in another layer already containing another version...Im questioning how any of this is even relevant...to anything...
  4. Dec 31, 2011 #3


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    One theory is that television has given up on trying to educate/inform and now simply endeavors to BEMUSE the public.

    If you adopt that view then the solution is to have a look at the cosmo research literature directly and forget about the gee-whiz telly specials. It's a bumpy road either way you go.

    Most of the cosmo literature doesn't have to do with multiple universes.

    But Hawking wants to sell books, so he writes Multiversery. And television producers want to get high viewer ratings, so they feature appearances by personalities like Hawking, Kaku, and understudy apprentice-personalities. There is a kind of market synergy between pop-sci books and the pop-sci tube. Or so it seems to me.

    Just say if you want links to the straight noncommercial quantum cosmology literature. You can scan down the titles and get some idea of what they are talking about without drowning in technical detail. There's a lot of it and very little has to do with string or M-theory or bubbles of alternative universe. Basically they are focusing on trying to understand our own and how the expansion process could have gotten started, based on what we can see.
    Last edited: Dec 31, 2011
  5. Dec 31, 2011 #4
    So what you are saying is, there is no validity to the Multiverse theory? That the rest of the academic community has stood back while some of the major contributors to the field simply want to make money off dullards like me...and nothing what so ever to do with unworkable odds? If this were the case, then it's strange to me that the rest of the academic community would allow this to continue unchallenged...publicly challenged...BBC "dont believe the hype" type challenged...

    Links would be great :)

    On a side note - it is great to see how much mental energies have been invested in one question relating to expansion. It would be even more awesome to think as much time could be spent on coming up with a more constructive way to deal with the resulting "life" that has been afforded us...Starvation seems to be as unsolvable as the mysteries of origin..
    Last edited: Dec 31, 2011
  6. Jan 2, 2012 #5
    M-theory takes place in 11 dimensions, with one time D and 10 space D. But, we can only see 4 dimensions, one time D and 3 space D. One way of correlating M-theory with what we can observe is to compactify the extra dimensions so that the 7 extra dimensions are so small as to be undetectable. If our universe is infinite, then there should be enough degrees of freedom in M-theory to allow "parallel universes" to also be infinite. It’s like slicing a loaf of 5D bread, were each slice is 4D and has one time D and 3 infinite space D.
    Last edited: Jan 2, 2012
  7. Jan 2, 2012 #6
    I dont have an issue with that if we are arguing that the universe is infinite, then, without all the fancy math, the resulting layers/parallels/dimensions, existing in the same space, would inherit this quality and be included when qualifying the universe as infinite. I have issue with saying that these parallels are independant of the universe, and probably, in this instance, have an unclear picture of what is included in the current definition of the word universe. To me the "space" as well as the observable matter, and the elusive elements of dark flow/matter, are included in that label, and therefore all other "dimensions".

    The quoted section you have selected addresses a different model, and that is the finite universe with other universes outside of it.

    I have been led to believe that some theoretical physicists like DR. Laura Mersini, have interpreted an apparent cold spot observed against the CMBR, as the potential existence of another universe outside ours, close enough to have a gravitational attraction, drawing matter in this universe toward the other. This I have a real issue with. At least it is admitted to be considered contraversial to date. Something to do with dark flow?


    Before anyone suggests to keep away from the more theoretical forms of current physics research, as a laymen, red shift or not, all forms are currently theoretical, no?

    One of the best responses I have seen on here so far is in another thread that I dont really have the time to sift through and quote directly - says something like "we know something happened, it happened a long time ago"
    Last edited: Jan 2, 2012
  8. Jan 2, 2012 #7


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    Actually, we know a great deal about what must have happened a very long time ago. Unfortunately, we do not know the whole story.
  9. Jan 2, 2012 #8
    It's particles. NO, it's waves. Actually guys it's both!. Funny how we know, until we know better. *Edit - my point is this.

    We are running with the idea that this singularity, that ended with a big bang, is a hypothesis, confirmed by observations, oberservations that could very well align themselves with another hypothesis, one that someone much more imaginative that I could come up with. Sometimes the results of experimentation are qualified by the hypthesis being tested, actually in every instance the results are qualified by the hpothesis being tested.
    Last edited: Jan 2, 2012
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