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Will the Origin ever be known?

  1. Jul 23, 2012 #1
    I prefix this by saying I have never ever studied science nor was I even interested in it till after high school but the other day I had this thought.

    While we can maybe one day explain the universe. How will we ever explain the space its expanding into and how big is that space?

    This space that could be home to many universes and had to be there before the big bang so what created this empty space. And then you have to figure out what made that then that and then that it would be a endless question.

    Can anyone give their opinion or explain this to me? I just don't see how we could ever answer what was the first thing ever not just in our universe but just since the dawn of anything.

    I Apologise if I have posted this in the wrong section I think I have the right one.
     
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  3. Jul 23, 2012 #2
    In the old standard cosmology there was (1)no space or time before the big bang and (2)the universe is not expanding into anything, that assumes there is space there to expand into, but the big bang picture is an expansion of space time istelf.
    However this picture is now being questioned well (1) is , I dont think (2) is though.
    The big bang as the start of time itself is being questioned both by qunatum grvaity theories such loop quanutm comsology and string theory and by theories such as eternal inflation which imply our big bang is one of many.
    we dont know which if these theories are true, maybe none of them.
    Whether we will ever get to the ultimate answer is anyones guess, maybe we will, maybe we wont. I think science is really not about finding ultimate answers but its about pushing the envelope of both our knowledge and our ignorance (figuring what we need to know next) , that is certainly happening. But I suspect we have a long way to go.

    if you would like to learn more read some books on popular comsology.
    this one will help you get the basic big bang model, its aslo a great read:

    https://www.amazon.com/Big-Bang-Ori...43047404&sr=1-1&keywords=big+bang+simon+singh
    Here are some reccomendations for books that push particular pre big bang mdoels, one for the ekpyrotic model, the next for eternal inflation and the last for loop quantum comsology
    https://www.amazon.com/Endless-Universe-Beyond-Big-Bang/dp/0385509642
    http://www.amazon.co.uk/Many-Worlds-One-Search-Universes/dp/0809095238
    https://www.amazon.com/Once-Before-Time-Whole-Universe/dp/0307272850

    whilst these books push for particular models they also give a very good guide for the laymans to more basic cosmology.
    Enjoy.
     
    Last edited by a moderator: May 6, 2017
  4. Jul 23, 2012 #3
    Thank you for the reply and links i wish i could afford them. I'll check the library database :).

    Also you're right about us having to take it one step at a time I guess I jumped the gun asking if we ever find the big starting point and asking what made that and so forth was more than a bit of a jump. To me the old theory is kind of silly if physics on earth are any comparison anything that is expanding first needs the space to expand into, if not it's not possible for it to expand I don't know of any examples of this happening anywhere.

    A part of me wants to be alive 1000 years from now just to obtain the knowledge we have learned by then but then I guess we'll just be curious about other things.

    thanks again
     
    Last edited by a moderator: May 6, 2017
  5. Jul 23, 2012 #4
    Well as I said i dont believe any of the new ideas challenge this particular assumption that universe is not expanding into some pre existing space but creating new space or stretching existing space. ( Ive never been perfectly clear on the difference , maybe someone else can comment on that and help us both out). Rather these other theories challenge the idea of the start of all things 13.7 bln year ago, they imply a pre big bang history.
    If you cant afford any of those books and cant get them from the library. Read this as a basic primer:
    http://map.gsfc.nasa.gov/universe/WMAP_Universe.pdf

    Here are some different models for the early universe, you can google or check on wikipedia these terms but remember , no one knows which of these models are correct and it may be none of them, we shall see:
    "loop quantum cosmology"
    "eternal inflation"
    "ekpyrotic model"
    "Caroll Chen model"
    Conformal Cyclic Cosmology"
    "Baum Frampton Model"
     
    Last edited: Jul 23, 2012
  6. Jul 23, 2012 #5
    It's only an endless question within the context of our limited understanding of existence: you're attempting to apply our rules of existence (cause and effect) beyond which they may apply, beyond creation. 2000 years ago we thought the earth was flat and held-up on a stack of turtles, one on top the other. But it's not turtles all the way down (metaphorically speaking), things change, qualitatively so, so that concepts we use to describe Nature at one level such as the apparent flat earth at a small scale, may not apply at another level such as a spherical earth at a larger level. And in the same way applied to beyond the Big Bang, something qualitatively different may be needed to describe it, and that descripiton may not include cause-and-effect, time, matter, distance, or other common phenomena we observe in our Universe: presupposing an endless regression you speak of may simply be applying the wrong rules.
     
  7. Jul 27, 2012 #6

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    Well you can also argue that this space or existence always "existed".

    I mean assume nothing as your starting point, how can you create something from nothing?
     
  8. Jul 27, 2012 #7
    Is it possible the word "nothing " is more ambiguous than people might think? What counts as nothing? A vacuum? a state with no sapce or time? A state with no space or time or laws of physics? A state with no space or time or laws of physics or laws of logic?
     
  9. Jul 27, 2012 #8
    Easy:

    [tex]\sum_{n=1}^{\infty} \frac{1}{n^2}=\frac{\pi^2}{6}[/tex]

    Think about it: If I take a finite sum of rational numbers, I get a rational number. However, once I traject through the singularity of infinity, the rules change. Because of the singuarity, I've created an irrational number from non-irrational numbers. Something qualitatively new has emerged by passing through a critical point, in this case moving from finite to infinite. If this were applied to our Universe, we could be asking how can something (irrational numbers) is created from nothing (the absence of irrational numbers). And the answer is the qualitative change that often accompanies a transit through a critical point.
     
    Last edited: Jul 27, 2012
  10. Jul 27, 2012 #9

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    Bad analogy.

    We define in real analysis irrational numbers as the limit of rational numbers, such that limit itself doesn't coincide with the rationals.

    Irrational numbers arise quite naturally in geometry too.

    When I mean nothing, I mean nothing.

    nothing = absence of something.

    It's OK, there will always be something.
     
  11. Jul 27, 2012 #10
    Ok, maybe it's not the best way to explain it. However I perfer to take a more general definition of nothing:

    nothing=qualitatively different from something.


    Isn't dark matter qualitatively different from matter? If so then I would accept dark matter as "nothing".
     
  12. Jul 27, 2012 #11

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    Then how do you define "something"?

    I guess we can discuss this philosophically.

    The end of the day, physicists try to look on concrete problems, even in cosmology. (unless you got lucky and are prestigious theoretical cosmologist).

    There was a book I once lend on nothing by cosmologist Barrow from Cambridge.

    Here's the a link for the title:

    http://www.amazon.co.uk/The-Book-Nothing-John-Barrow/dp/0099288451

    Perhaps I'll give it another look the next time I go to my uni.
     
  13. Jul 27, 2012 #12
    something=qualitiatively different from nothing and separated from it by a critical point.

    I don't think they like philosophy in here, not at all I think. They're just being nice letting it go this far. I like John Barrow. He wrote "The World within the World", one of my favorite books.

    I'm simply trying to resolve the many paradoxes we encounter in Astronomy. I believe we can do this with Catastrophe Theory and the qualiatiative change that occurs trajecting through a catastrophe (critical point). For me, that perspecitve resolves many, many of the puzzling paradoxes we encounter about life and the Universe including how something (our Universe) can emerge from nothing (something qualitatively different from our Universe) if a critical point is involved and the Big Bang seems to be a critical point.

    So that's my hard empirical evidence required for this sub-forum: I'm basing my view on cricical point dynamics we observe throughout the Universe and suggest that dynamics is an echo of what gave rise to our Universe.
     
    Last edited: Jul 27, 2012
  14. Jul 27, 2012 #13

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    You have there a circular definition.

    Not that it's bad, it's just not really convincing.

    As we can see it becomes a discussion over definitions.
    I can abandon my definition, but why?

    Your "nothing" looks like still "something" in my definitions.
     
  15. Jul 27, 2012 #14

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    I believe the question is ultimately one of causality. In the affirmative case the answer is the universe is and always was eternal. It may have existed in many curious forms, but, each incarnation was preceded by some prior state. If the universe is acausal it had a definitive beginning - a 'creation' event some finite time in the past. This is the 'universe from nothing' idea. Both models are unsettling at some level. The universe ex nihilo model is obviously spooky, but, the eternal causality model implies 'something' has always existed - which confers a no less spooky quality to whatever that 'something' happens to be. So, you end up with something that looks 'supernatural' no matter how you slice it, IMO. I prefer the big bang ex nihilo. Yes, you get stuck with pink fairies, but, it really doesn't look any worse than the evidence for branes, bulks, or anthropery. An interesting related discussion is here http://arxiv.org/abs/1202.4545.
     
    Last edited: Jul 27, 2012
  16. Jul 28, 2012 #15

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    I am not sure both of these possiblities are spooky on the same level.

    I mean, I can live with infinite successions of cause and effects of somethings, I mean you would still be puzzled by this sequence of events, but in your everyday life you see cause and effect all the time. If on the other hand everything started from nothing, how did something get out of it?

    Well, philosophical questions rarely get answered. (I guess this is why I didn't continue in theoretical physics/theoretical cosmology, job oppurtunities are scarce, and I prefer to be an armchair cosmologist keep dealing with the math side of things, may they be pure or applied math than dealing with the physics).
     
  17. Jul 29, 2012 #16
    Halliwell call it "Quantum Fuzz"

    i prefer to think on minimal entropy state, quasi zero, pintpoint small deviations give rise to universe (s).
    in that state with cause and effect in no order that system does not decay, only in some points, and the vasteness give room to endless universes and endeless existence itself.
     
    Last edited: Jul 29, 2012
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