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Big bang according to Quantum Mechanics?

  1. Sep 17, 2012 #1
    I hope I will be welcome here. Please keep in mind that I have a very limited and novice understand of science and maths. I guess you could say I'm here to understand the big bang and how it can be plausible for our universe to exist the way it does.

    Several years ago I saw this production called "Nova: The Elegant Universe". It goes over things like Quantum mechanics, string theory, alternate dimensions, etc. Much to my surprise I did not find what I saw to be hard to understand at all, that is, if I'm to believe I'm correct in my understanding of it. Coming from a religious background, I was basically looking for an answer which proves how the universe can exist the way it does without needing a 'God'. I do believe Quantum mechanics provides this answer. It's quite fascinating.

    Now, my problem is that recently I've become very interested in this once again. Alternate realities, etc. In the last few days I've tried doing research to confirm that my understanding of quantum mechanics is correct. While it does seem I'm correct, I was shocked that no articles I read provided the same, simple answer I have in my head for why the universe exists as it does. I will provide my own understanding here, and I ask that you confirm whether or not I'm correct. But I find it strange that the explanation isn't simplified anywhere else. Simplifying the explanation for someone at a novice level (like me) would help put to rest claims like "the universe needs a god in order to exist". That's why I find it strange that I cannot find the elaboration elsewhere. It would be quite easy to summarize for beginners, yet it appears it's not been done. Not even "Nova: The Elegant Universe" explained it in that detail; I merely had to connect the dots myself. This gives me a strange feeling that either my conclusions are entirely wrong, or that my understanding is much more advanced than I think.

    Believe me, I'm not trying to preach science here. I'm asking you to confirm and correct me where/if I'm wrong, and then explain things to me better.

    My understanding of how our universe began according to quantum mechanics is:

    Basically we are incapable of comprehending all the phenomenon of our universe. The universe itself is a combination of possibly an infinite number of 'alternate realities'. These realities present themselves whenever *anything* within the universe is prone to chance. Any time an event is prone to chance, each possible chance does occur. As flesh/blood creatures we are incapable of experiencing more than one reality, more than one consciousness, yet there are in fact an 'infinite' amount of ourselves existing within these alternate realities which, likes ours, exist due to variables and random chances.

    Since every possible chance that can occur does occur, this means that some (and many) realities have very bizarre things happening within which are in fact very scientifically unlikely, or even near impossible. Even if there is only a 0.000000000000000000000000001% chance of an event occurring, that event does occur, though it is unlikely that 'we' will actually experience it for 'ourselves'. I find that this theory could be used to potentially explain nearly all strange happenings within our universe.

    What this means is that the big bang - and our universe - actually exist due to the occurrences of very unlikely chances becoming reality. The chance of the 'big bang' happening was probably nearly impossible. Yet because of quantum mechanics, it did happen. Even more unlikely was that a big bang would result in the complex universe we have today - but that naturally happens as well due to chance. But in many realities, the universe does not exist. The big bang did not happen. In other realities, the big bang happened but the universe burned out before it was able to expand significantly. And there are certainly other realities where the universe resulted in a much more complex state than ours. As unlikely as the big bang was, the concept of life existing is also extremely unlikely. Yet, it happened. What this means, I think, is that we are part of a very beautiful reality. We are part of an *extremely* unlikely reality which exists due to a series of coincidences and amazingly complex events occurring to bring us to where we are today. Chances are there may be more realities where none of this exists, than realities where it does exist. Then again, the more that exists and the more complex the things within a universe are means many more events being left up to chance, which means an even greater splitting of reality. If quantum mechanics is true then reality must be splitting a part likely a near infinite amount of times every millisecond due to all the phenomenon and chances occurring within the universe, on planets, and here on earth.

    When I think about things like this, I find it almost silly to ask "why" or treat something as impossible whenever we cannot explain a phenomenon. Some people act is if our universe - our reality - is so special and so 'unlikely', when in fact it is just another chunk of many other realities happening simultaneously as ours. Each reality is equal to ours, and just because we are experiencing whichever reality doesn't mean it's "all that exists". Virtually any reality you can imagine is real, and is just as real for the inhabitants as this one is for you.


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    Am I right about this, more or less?

    Again, I just don't understand why this isn't explained in this simplified format on other websites and articles. It seems that most information on this expects the reader to connect the dots for themselves. But I feel like the point is been missed by all sorts of people who need to resort to unscientific claims to explain why the universe, and life, exists.

    It would appear to me that in quantum mechanics, the concept of the universe not existing is even more unlikely than the universe existing.
     
    Last edited: Sep 17, 2012
  2. jcsd
  3. Sep 17, 2012 #2
    Under the Many Worlds Interpretation of Quantum Mechanics, yes. This is one way of many of interpreting what the math tells us happens, and, at least for now, one can't distinguish which interpretation's "true," or even if they're all true.

    Same.

    In theory, that's possible, though it seems a bit overspeculative.

    Interesting. This seems somewhat like the Anthropic Principle, though not exactly so.
     
  4. Sep 17, 2012 #3
    Thank you for your reply.

    But I'm wondering, if the former are true, why isn't the latter part you quoted true?

    Having heard the theories in the former, I automatically assumed that the big bang would be the result of the exact same phenomenon. I mean, why wouldn't it be?

    After reading through this site a bit, I may have seen what appears to be references stating that quantum mechanics (ie, infinite realities) did not come into existence until after planck time. But if this is the case, we're still basically at square one when it comes to explaining what exactly ignited the big bang. (Nova: The Elegant Universe also mentioned something about a possible collision of two or more universes resulting in the big bang which created our universe).

    From my limited understanding, it does appear to me that my explanation does explain a great deal of why, or even how, the big bang happened. I did truly believe that this is what the theory itself was saying all a long. And if I'm right, then more effort should definitely be taken to explain this stuff to the scientifically illiterate.

    Also, forgive the way I define Quantum Mechanics. I don't think I've truly grasped the definition of it. But what I'm referring to are the theories Quantum mechanics supposedly puts forth about 'infinite alternate realities' based upon anything prone to chance.

    In the event that this 'infinite alternate reality' stuff is wrong, there is another theory I've heard which could explain the improbabilities of the universe and life. Basically it would involve a chain of universes expanding, collapsing, and then expanding again. Didn't I hear that dark matter may be radiation left over from a previous universe?

    The concept of how we can exist does fascinate me. I'm wired to be naturally inclined to resort to religion, but I'm really seeing the problems with that. But it's fascinating, because so I've heard..... life is so unlikely to exist without an intelligent design/creator that you'd have a better chance of a tornado zooming through a junk yard creating a jumbo jet (interestingly, this could/would happen with quantum mechanics).
     
  5. Sep 17, 2012 #4
    Again, the former two quotes are "sort of" true, just one of the many ways of visualizing what the math tells us is going to happen.

    Seems like you've stumbled on something close to a bit of philosophy called the Anthropic Principle. It's almost impossible to convey in words, or at least my interpretation of it is impossible to convey in words. The best explanation I've seen is http://curiosity.discovery.com/question/what-anthropic-principle [Broken]

    And yes, I'm about to address the rest of your post.
     
    Last edited by a moderator: May 6, 2017
  6. Sep 17, 2012 #5
    So it's not literally true that there are many alternate realities? In what way are they "sort of" true?

    If it is literally true, I still don't understand why my understanding of the big bang wouldn't be true? I need someone to elaborate on that part. Because to me it feels like this theory goes hand in hand with the concept of the big bang merely being a random quantum coincidence that was bound to happen even if the chance of it happening was a near 0%.

    You mentioned "Anthropic Principle". I looked this up and saw a bunch of religious stuff. That wasn't really what I was describing at all. While I was trying to compliment the beauty within our reality, I was merely saying that our existence is a very strange coincidence which we are lucky to experience. Side-by-side with our existence are alternate realities where every single chance possible does occur. We are one of those chances. All chances do occur and branch off into their own realities. At times it may appear there is something divine about our existence... but no, it is merely an unlikely coincidence. The big bang.... the universe.... life itself.... the chance of all this existing may be near a dead 0%, but here we are. As the theory states, even if there's only a 0.000000000000000000000001% chance of something occurring, it does occur within its own reality. We are in one of those realities. It happened even though it was totally improbable. In other realities there are even stranger things happening.

    I should probably wait for some other people to comment now.
     
  7. Sep 17, 2012 #6
    Basically. We do know that whatever theory we come up with has to be indistinguishable from QM in the experiments we've done, somewhat like how Special Relativity is effectively indistinguishable from Classical Mechanics in the velocities we encounter every day. The new theory may be effectively QM.

    Possible. A bit overly speculative.

    Unfortunately, this does rely on a specific interpretation of QM and is basically invalid in any other interpretation.

    Done. If I'm remembering my history correctly, QM is basically the assumption that light waves only come in integer multiples of a certain energy (dependent on the frequency) and various other similar assumptions and their consequences.

    I'm a bit skeptical about this, as it's overly speculative. (Sorry, what I should point out now is that these forums aren't necessarily for theoretical physics, or at least debating theories that, for now, result in no testable predictions.)

    Certainly nothing wrong with that! Well, as you noted, there are, in a sense, various problems in scientific discussion, but I'm not trying to come off as anti-religious here.

    Well, Many Worlds Interpretation, yes. :tongue:

    Sorry if some of my comments seemed a little nasty, my attempt is to try to be friendly, though I sometimes don't do so perfectly. What you've stumbled upon does seem somewhat like an odd manifestation of the Anthropic Principle, sorry if I seem to be repeating this over and over.

    Now to go over the post directly previous to this one.
     
  8. Sep 17, 2012 #7

    HallsofIvy

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    But if the big bang had NOT happened, we would not be here to ask about it. From that point of view, "nearly impossible" or not, it had to happen.
     
  9. Sep 17, 2012 #8
    The theory of there being many alternate realities, again, is one way of a bunch of explaining what the math (which we've experimentally failed to disprove) tells us will happen. Perhaps you should see Wikipedia's list of interpretations.

    Interesting. The http://curiosity.discovery.com/question/what-anthropic-principle [Broken] I provided previously should be the best I've seen at explaining it.

     
    Last edited by a moderator: May 6, 2017
  10. Sep 17, 2012 #9
    Ah, another excellent, and very brief, explanation of the Anthropic Principle. I'll have to make a .rtf file on my computer with that exact quote.
     
  11. Sep 17, 2012 #10
    Hmmmm. I still don't know if I really understand this Anthropic Principle. It does sound a lot to me like it's pointing towards a "god" or "higher power" of some sort... and I do really want to distance myself from that. And I don't want to push my theories, either, if they are wrong and simply don't fit. But I'm just a bit confused and frustrated (:-p) now because it would appear my way of explaining existence doesn't fit. I do wish I had a way of explaining all the 'coincidences' which spawned the universe and brought us here.

    The Anthropic Principle suggests that the universe is naturally inclined for coincidental, bizarre, or 'unlikely' conditions to arise and result in complex lifeforms, intelligence, etc. The question must be asked, "why is the universe" like this"? Sorry if I'm not following properly. But I think I just saw a Christian website using Anthropic Principle to explain existence. That tells me it's not good. :-p

    What I was trying to say, is that our reality gives the impression "Anthropic Principle" is right, simply because of the "quantum reality" we are in. Since all coincidences and chances occur, we were led down a road of coincidences which created our "intelligent" reality. This is why it's so easy to get the impression of there being gods, intelligent design, etc. I do believe what I was putting forth is much different than Anthropic Principle, since my idea is that we *are* indeed a coincidence and an unlikely chance, since all coincidences and chances do happen throughout different realities. But hmmmm. Perhaps I am wrong.

    Yes, true, but I do find that type of statement a little simplistic, even if me saying that is like the pot calling the kettle black. The idea I was trying to put forth is we do indeed exist because of the big bang, but that the big bang was something that was going to happen one way or another, since all chances do occur, however unlikely they are. Same with the evolution of life. And that's why we're lucky enough to be here talking about it. In some realities earth has nothing more than micro organisms and it will never become anything more than that.

    I guess I am a bit Sci-Fish :-p
    I did see an episode of Star Trek: TNG that uses the "infinite reality" theory I'm using.

    I realize this. I guess I'm just looking for the best scientific theory which best explains how the universe and life exists as it does. It does seem very unlikely that after one big bang, the entire universe evolved as it did. Sometimes I imagine an infinite chain of universes expanding and eventually contracting back into a vaccum.... meaning that eventually something spectacular like our universe (or better) will result. But I'm no scientist.

    Actually, I am basically anti-religious. Most religions are so silly and contradicted that science, or even a random theory like mine, are much more likely even if they don't yet have all the answers. Still, I do often feel inclined to make the leap to a 'god' or 'higher power'. Right now I'm more of an ancient alien theorist. I guess there are many possibilities. I've heard theories that our universe might exist in some alien lab as an experiment. The universe they are in could have such vastly different laws of physics, and the beings themselves might be so different from us, that the answers to everything exist only there, and therefore, we cannot comprehend it. If we're a "universe within a universe", or an infinite chain of such, there's no telling what the "outer universe" is like. lol
    Still I've heard theories that our universe and existence might be a virtual reality.

    So it is not generally agreed upon that life on earth is more unlikely than 'a tornado zooming through a junk yard and creating a jumbo jet'? I'd be interested in hearing more about this. There's so much garbage on the Internet that tries to force some religious, "intelligent design" view down your throat.... and I am someone who agrees there is *probably* a god or higher power. But my head tells me there's not.

    No, don't worry. I wasn't thinking that. I do realize what needs to be said during a debate/correction. Actually, I'm relieved that so far this has gone over much better than I thought it would. I'm just summarizing my understanding as best as possible. It may seem like I'm pushing it as "the truth", but I'm just looking for a confirmation/correction. Any how, I am frustrated now.... a bit confused and lost by all of this. O_O But don't worry.
     
  12. Sep 17, 2012 #11
    :tongue: It's been taken out of context sometimes. It can be a little confusing, especially when someone's trying to explain it, as I have yet to see an explanation that seems to convey it quite well. If I'm getting your theory right, it's saying that the MWI suggests an infinite number of universes, some of which support life, so of course we're going to exist. Or something along those lines.

    Yea, I suppose it's still a bit of an open question, as the Anthropic Principle has some valid criticisms, probably the most important of which being that it's not truly science, it's philosophy.

    I will admit that I find bits of some religions silly.

    :smile: Just so long as you don't start looking like a conspiracy theorist.

    Apologies, my response was poorly worded. I was replying to the bit about how that would happen in one universe.

    QM is confusing at best, and the (somewhat philosophical) discussion we've had is probably even more confusing. I'm even a little confused. :tongue:
     
  13. Sep 17, 2012 #12
    Hehe, it looks like you do have a good understanding of my "theory".

    It's a shame more people won't reply to this thread.... I'd like to get more of an input.

    In the mean time, I'd like to hear more about current scientific theories which attempt to explain how the big bang happened, what ignited it, and what, if anything, came before it? Should I start a new topic somewhere for this question?

    Thanks.
     
  14. Sep 17, 2012 #13
    Hmmm ... there are a few, none of which we have any reason yet to think happened. My view is that it's invalid to try to define time at or before the moment of the BB, but there have been plenty of alternatives suggested, none of which I can think of at the moment.
     
  15. Sep 21, 2012 #14
    The anthropic principal does not describe how or why particular things arise, it is merely a reflection on what we should expect to see.

    For instance, our type of biology requires liquid water. Liquid water can only exist a certain distance from a host star (too close, it boils, too far, it freezes). Anthropic reason simply tells us we should not be surprised when we measure Earth's distance from the sun and find it is just the right distance to allow liquid water. If that were not the case, then obviously we never would have evolved here in this form in the first place.
    Anthropic reasoning stands contrary to fine-tuning or intelligent design for the same reason. It says we should not be surprised or seek higher explanations for the fact we occupy a universe that supports life. If the universe did not, we wouldn't be here to consider it.

    A lot of scientists don't like anthropic reasoning -- not because it is wrong -- but because to a certain extent it tells us to abandon the persuit of basic principals, and accept that some apparently unlikely features of our universe are merely environmental coincidences.

    **edit
    I should have added that it functions as a principle only in one of various multi-verse models where you expect every combination of parameters to be realized.
     
  16. Sep 21, 2012 #15

    Fredrik

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    To me it suggests something that's almost the opposite of that: That in some sense, everything that can happen is happening.

    Edit: I should perhaps also say that I really mean "suggests", not "implies", and that speculation about these things are just that, speculation, not science.
     
    Last edited: Sep 21, 2012
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