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How can a universe come from nothing?

  1. May 25, 2013 #1
    Hello. I know all of the basics of physics (relativity, most basics of quantum physics, and etc) but I can't quite put my finger on the origin of the big bang (as I think most people do). I can't seem to find any decent information on it. How much do we actually know about the origins of the universe? I'm extremely interested in origins, the origins of life has been satisfactorily answered for me (evolution and etc), but the origin of the universe seems to have no real good, definitive answers on it.

    From what I've uncovered, when the universe began there was large amounts of matter and anti matter which annihilated each other, resulting in the expansion of the universe. There was more matter than anti matter (or antimatter has properties which make it less prominent), and we are just a small percentage left over. I've wondered how these particles actually came into existence. From what I understand of quantum physics, virtual particles come in and out of existence all the time, but it's different at the start of the universe, there is no zero point energy field present if there is literally nothing, so how could these matter and anti matter particles form from absolute nothing? Even if there was a ZPF present, how does this large of an influx of particles come? Why does the universe pretty much stop this process after the big bang?

    I was able to sleep at night answering the question with another question lol: How can the universe NOT come from nothing? Which is a rather, less pessimistic question, but it raises another point: What could stop a universe from coming from nothing? If there is nothing stopping it, it could happen right? Even if there is a 1/100^100^100^100^100^10000000000 chance of a universe happening, it would have to happen.

    I don't find god (what some theists decide to answer the question with lol), or even some multiverse theories as sufficient answers, they are not testable as far as I know so I don't see how it is even a relevant answer to the questions we have about reality. I think they are just designed to dodge having to answer some of the big question (more so the explanation "god did it"). I'm open minded to a 'multiverse' theory even though I don't think it would be very probable. I understand that we as humans try to find causality relationships within everything, but I'm perfectly fine with a 'causeless' beginning, I can wrap my head around it. What I do want to know is what in physics could allow these particles to come into existence? And how did this imbalance of matter and antimatter occur?
     
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  3. May 25, 2013 #2

    Bandersnatch

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    Hi, mattattack.

    There you go, that's your answer.

    You might find Lawrence Krauss' ideas relevant to your line of inquiry. He wrote "Universe from nothing" recently, and is actively promoting the idea, but from what I gather it's hardly a definite answer.

    Also, I'm pretty sure the annihilation of matter and antimatter was not the driving force behind the initial expansion. You might want to review your knowledge a bit. S.Weinberg's "First three minutes" covers early universe and baryogenesis. A.Guth's "Inflationary Universe" might be a good start on the expansion process.
     
  4. May 25, 2013 #3

    phinds

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    This question is asked here many times a year. Do a forum search. You won't get an answer, since so far there isn't one, but you'll get lots of discussions of the various theories.
     
  5. Jun 16, 2013 #4
    Marcus made one of his well reasoned posts on this subject a few years back. I don't remember his exact words, but the message was to the effect that nature is not ready to answer this question - but in reality it is us who do not have enough information to pose the question correctly.
     
  6. Jun 16, 2013 #5

    Chronos

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    Krauss has argued the universe is nothing more than a collection of fields and particles whose net energy sums up to exactly zero.
     
    Last edited: Jun 16, 2013
  7. Jun 16, 2013 #6
    Maybe it's a symmetry... no one seems to have a problem with nothing coming from something. Nothing can come from anything, even nothing. So there is always nothing.
    Maybe something is similar; something can come from something, anything, and nothing, too.
     
  8. Jun 17, 2013 #7
    We know a lot about the origin of the universe up to a certain point after the big bang. Certainly after the first few minutes things are very much agreed upon. You can see a timeline on Wikipedia here:
    http://en.wikipedia.org/wiki/Timeline_of_the_universe
    Grand Unified theories have not been verified by data and as we get earlier than that there is more debate.
    Inflation has a reasonable consensus around it but there is still some room for debate there, read here for more:
    http://www.nature.com/news/2009/090415/full/458820a.html
    It’s been argued that the process of inflation can create all the matter and energy that we see today. See the text book “Universe” by Friedman et all for a good explanation.
    It’s also been argued that inflation generates a multiverse; see other threads about this here in the forums.
    The debates about inflation are ongoing, some don’t accept it at all, and others accept it but deny it leads to a multiverse. I think most accept it and may be unaware about the debate regarding eternal inflation. Future gravity waves mission and polarization maps of the Cmb will hopefully shed more light on the issue.
    Before inflation we need quantum gravity and we don’t have a well tested theory. Hopefully new models such as Loop quantum cosmology and Horava gravity may be testable in the future. A common prediction of these models is the big bang was a bounce from a universe that collapsed. Again future gravity wave data may shed light on this.
    The asymmetry between matter and anti matter is a mystery at the moment.

    Lawrence Krauss has promoted the universe from nothing idea that relies on a proposal form Alex Vilenkin made in the 1980’s. This idea is that space and time can tunnel into existence in a similar way that virtual particles can tunnel into existence. To me he seems to be claiming that if this happened and made our universe the initial event must have inflated, if inflation happened we should see a flat universe, and we do ish. To my knowledge most project say flat such as WMAP, Boomerang and Planck. But the South pole telescope detected some small positive curvature. So I think the consensus is flat , but there is still some room for disagreement. My issue with Krauss is that bouncing cosmologies (a universe from something if you like) may also undergo inflation. LQC seems to predict inflation. So I don’t think his case is as strong as some people think. It’s an interesting idea but it’s more of a guess of what quantum gravity might imply rather than a necessary implication of a well developed quantum gravity theory in IMHO.
     
    Last edited: Jun 17, 2013
  9. Jun 17, 2013 #8
    This question really confuses me. I can understand "coming out of something" in context of a pseudo-Riemannian manifold, where one of the dimensions is timelike. But that's not nothing, rather it's most definitely already something. Without any manifold where events can exist and be ordered, the concept of "coming" makes no sense to me.
     
  10. Jun 17, 2013 #9
    Some time from now someone will write a program which will simulate a physical reality evolving through a computation process leading to an identical universe as ours. After that we will realise that thats exactly how it happens; we are the cause in a looped chain of endless reiteration.

    Thats if you ask me.
     
    Last edited: Jun 17, 2013
  11. Jun 17, 2013 #10
    By the way - the origin of life is unknown. The theory of evolution can not explain how the life proces began, only how it evolved to what we see today after it originated.

    Best, Henrik
     
  12. Jun 17, 2013 #11
    Were closer to understanding how life began than the universe. We have created from scratch artificial single cell organisms.

    http://news.nationalgeographic.com/...ynthetic-dna-evolution-genetics-life-science/

    google DNA creation in the lab. You will pull up numerous articles.
    In 2009 they managed to create reproducing, evolving RNA strands that share key aspects of life.
    However this is a subject for another thread.
     
  13. Jun 17, 2013 #12

    RUTA

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    From the standpoint of general relativity (GR), there are many solutions to Einstein's equations (EE) that provide a metric (g) and stress-energy tensor (SET) combo on the spacetime manifold. Now consider one of these solutions we call a "big bang solution." This solution may be carved into time-evolved 3D spatial hypersurfaces. You can point to one of the 3D surfaces (the universe at time t) and ask, "Where did that come from?" The answer in the context of time-evolved 3D hypersurfaces would be "the 3D hypersurface at time t-dt." But if you keep asking and answering this question in the same fashion, you eventually come to the big bang and there is no surface prior to this, so your question is no longer meaningful. Of course, it's not a "real" mystery as to where the big bang came from, you understand that the way you were posing and answering the question created a "faux" mystery. You were working in the dynamical perspective (time-evolved 3D entities) instead of the 4D perspective of the theory (GR) which created the solution proper. The reason any given point on the spacetime manifold has the values of g and SET that it does is best answered via GR, i.e., those values of g and SET at that point are consistent with those in the immediate vicinity per EE. It's explanation via "self-consistency" rather than dynamism because in 4D nothing is moving. Here is a nice quote:

    "There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes. [...] In particular, one does not think of particles as "moving through" space-time, or as "following along" their world-lines. Rather, particles are just "in" space-time, once and for all, and the world-line represents, all at once the complete life history of the particle."

    Relativity from A to B by Dr. Robert Geroch, U. of Chicago
     
  14. Jun 17, 2013 #13
    Hawkings and Krauss paragraphs

    "Because there is a law such as gravity, the universe can and will create itself from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist. It is not necessary to invoke God to light the blue touch paper and set the universe going." Stephen Hawking, The Grand Design.

    "there are remarkable, testable arguments that provide firmer empirical evidence of the possibility that our universe arose from nothing. ... If our universe arose spontaneously from nothing at all, one might predict that its total energy should be zero. And when we measure the total energy of the universe, which could have been anything, the answer turns out to be the only one consistent with this possibility." Lawrence Krauss, article "Our Spontaneous Universe"
     
  15. Jun 18, 2013 #14
    The problem with Hawking and Krauss's arguments is that they inevitably postulate an underlying physical mechanism to explain spontaneous creation of a certain type (particles, space, time, etc.). Which inevitably pushes the problem back to the postulated physical mechanism, and therefore solves nothing. Because physics postulates entities of one type to explain another, this problem is probably beyond physics.

    I think David Albert has already refuted their arguments with similar considerations...
    http://www.nytimes.com/2012/03/25/b...e-from-nothing-by-lawrence-m-krauss.html?_r=0
     
  16. Jun 18, 2013 #15

    Fredrik

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    I don't think anything good can come from this thread, so I'm going to close it. You may have noticed that we have already deleted some religious comments and the replies to those comments.

    Note that none of the established theories of physics says that something comes from nothing. People who suggest that there may be something to that idea are speculating. This makes the topic inappropriate at Physics Forums.

    I will probably delete this thread later today, when the participants have had a reasonable chance to see the last few posts including this one.
     
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