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Thread: Quarks, Early Universe / Uncertantiy Principle ?

  1. #1 Quarks, Early Universe / Uncertantiy Principle ? 
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    Quarks were formed during inflation in the big bang. The smallest amount of time we can extrapolate back towards the big bang to is 10^-43 seconds, where it is thought the temperature was 10^32 and a density that is not describable. So during this time, it is thought there is only one force; a combination of four forces.

    So the question is, where did the forces come from? Where did matter and temperature come from?

    Is this unknown unless you invoke M theory or the uncertainty principle?

    Also can someone explain the uncertainty principle. Does nothing mean absolute nothing? Or does nothing mean not matter but forces and vacuum?


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    Forum Radioactive Isotope MagiMaster's Avatar
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    You seem to be conflating a lot of tangentially related ideas. Sure, in the final picture, they'll all matter, but your initial question, IIRC, comes down to spontaneous symmetry breaking.


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    Quote Originally Posted by MagiMaster
    You seem to be conflating a lot of tangentially related ideas. Sure, in the final picture, they'll all matter, but your initial question, IIRC, comes down to spontaneous symmetry breaking.

    So if you have a speck of 10^-99 cubic cm that can be created out of nothing, following the uncertainty principle, then this speck goes on to create the universe; were forces created during that time, or did inflation create forces?

    Is nothing absolutely nothing in the uncertainty principle?
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  5. #4  
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    Quote Originally Posted by juantonwan

    Is nothing absolutely nothing in the uncertainty principle?
    The quantum vacuum is far from absolutely nothing.

    http://en.wikipedia.org/wiki/Vacuum_state
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    Quote Originally Posted by DrRocket
    Quote Originally Posted by juantonwan

    Is nothing absolutely nothing in the uncertainty principle?
    The quantum vacuum is far from absolutely nothing.

    http://en.wikipedia.org/wiki/Vacuum_state
    Where does the energy in the vacuum state come from?

    Basically I am trying to figure out an absolute starting point? It seems this is basically unknown unless you invoke quantum theories.

    How did anything start?
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  7. #6  
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    Quote Originally Posted by juantonwan
    Quote Originally Posted by DrRocket
    Quote Originally Posted by juantonwan

    Is nothing absolutely nothing in the uncertainty principle?
    The quantum vacuum is far from absolutely nothing.

    http://en.wikipedia.org/wiki/Vacuum_state
    Where does the energy in the vacuum state come from?

    Basically I am trying to figure out an absolute starting point? It seems this is basically unknown unless you invoke quantum theories.

    How did anything start?
    The nature of the vacuum is largely due to the Heisenberg uncertainty principle.

    Of course you need to invoke quantum theories. We are talking about the vacuum state of a quantum theory.

    There are no "absolute starting points". I have no idea what that would even mean.
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    Forum Ph.D. Heinsbergrelatz's Avatar
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    Also can someone explain the uncertainty principle
    the Uncertainty principle was introduced by a Nobel Laureate Wener Heisenberg.
    Basically what this principle tries to tell you is that the position and the momentum of the particle cannot be simultaneously measured with arbitrarily high precision. Another words, one cant determine the position and the velocity of a particle at the same time.

    But the story doesn't end here, and leads to the point where Einstein was unhappy with this formulation, thereby giving the QM party logical approaches towards his disagreement regarding the principle(along with two other physicist , Rosen and Podolsky). his approach was that the outcome of a measurement could be known before the measurement takes place
    This is known as the EPR paradox, but it was solved till one point with Bell's experiment. This i dont know quite in detail. But in conclusion Einstein thought that Quantum Mechanics was not a complete theory.
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  9. #8  
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    Quote Originally Posted by Heinsbergrelatz
    Also can someone explain the uncertainty principle
    the Uncertainty principle was introduced by a Nobel Laureate Wener Heisenberg.
    Basically what this principle tries to tell you is that the position and the momentum of the particle cannot be simultaneously measured with arbitrarily high precision. Another words, one cant determine the position and the velocity of a particle at the same time.

    But the story doesn't end here, and leads to the point where Einstein was unhappy with this formulation, thereby giving the QM party logical approaches towards his disagreement regarding the principle(along with two other physicist , Rosen and Podolsky). his approach was that the outcome of a measurement could be known before the measurement takes place
    This is known as the EPR paradox, but it was solved till one point with Bell's experiment. This i dont know quite in detail. But in conclusion Einstein thought that Quantum Mechanics was not a complete theory.
    The conclusion is that so far all experiment indicates that Einstein was wrong and his opponents were right. His EPR thought experiments have now been performed in the laboratory and the aspects that he thought to be so weird as to contradict reality have in fact been observed.
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    Forum Radioactive Isotope MagiMaster's Avatar
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    Quote Originally Posted by juantonwan
    Quote Originally Posted by MagiMaster
    You seem to be conflating a lot of tangentially related ideas. Sure, in the final picture, they'll all matter, but your initial question, IIRC, comes down to spontaneous symmetry breaking.

    So if you have a speck of 10^-99 cubic cm that can be created out of nothing, following the uncertainty principle, then this speck goes on to create the universe; were forces created during that time, or did inflation create forces?
    No one yet knows what happened to cause the big bang, if there ever was something that could be properly called a cause, but there was no vacuum at that time because there was no universe for there to be a vacuum in. IMO, it seems unlikely that the universe was created due to the uncertainty principle.
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  11. #10  
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    Quote Originally Posted by MagiMaster
    Quote Originally Posted by juantonwan
    Quote Originally Posted by MagiMaster
    You seem to be conflating a lot of tangentially related ideas. Sure, in the final picture, they'll all matter, but your initial question, IIRC, comes down to spontaneous symmetry breaking.

    So if you have a speck of 10^-99 cubic cm that can be created out of nothing, following the uncertainty principle, then this speck goes on to create the universe; were forces created during that time, or did inflation create forces?
    No one yet knows what happened to cause the big bang, if there ever was something that could be properly called a cause, but there was no vacuum at that time because there was no universe for there to be a vacuum in. IMO, it seems unlikely that the universe was created due to the uncertainty principle.
    This can be and has been argued ad nauseum.

    There is no "before" the big bang. The big bang is associated with spacetime, which includes all of space and all of time, all intertwined. It contains the past, present, and future. it is the whole enchilada. There is nothing else. No before, and no after. Since there is no before, nothing caused it. Neither is there an "elsewhere". Nor an "after".

    General relativity predicts a singularity near t=0. That means that the theory breaks down and nobody knows what is going on.

    Einstein-Cartan theory does not predict this singularity. Still nobody knows what is going on.

    It may be that quantum gravity is needed so that quantum effects and strong gravitational effects can be addressed simultaneously. We don't have such a theory yet. Nobody knows what is going on.

    A whole bunch of people have written books about the nature of the big bang. They don't know what is going on either, but they sure do make money selling books to other people who don't know what is going on.

    You can fill up an entire thread with your notions as to what "caused" the big bang. You will not be able to reach any conclusions, and will still not know what is going on, just like everybody else on the planet.

    The more knowledgeable people know that they don't know what is going on. The less knowledgeable and the outright deluded think they know what is going on. But they don't.

    So you have two choices. You can recognize that you don't know what is going on. Or you can fail to recognize that fact that believe that you know what is going on. But no matter what, you won't really know what is going on.

    Next topic ?
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    Quote Originally Posted by DrRocket
    Quote Originally Posted by MagiMaster
    No one yet knows what happened to cause the big bang, if there ever was something that could be properly called a cause, but there was no vacuum at that time because there was no universe for there to be a vacuum in. IMO, it seems unlikely that the universe was created due to the uncertainty principle.
    This can be and has been argued ad nauseum.

    There is no "before" the big bang. The big bang is associated with spacetime, which includes all of space and all of time, all intertwined. It contains the past, present, and future. it is the whole enchilada. There is nothing else. No before, and no after. Since there is no before, nothing caused it. Neither is there an "elsewhere". Nor an "after".

    General relativity predicts a singularity near t=0. That means that the theory breaks down and nobody knows what is going on.

    Einstein-Cartan theory does not predict this singularity. Still nobody knows what is going on.

    It may be that quantum gravity is needed so that quantum effects and strong gravitational effects can be addressed simultaneously. We don't have such a theory yet. Nobody knows what is going on.

    A whole bunch of people have written books about the nature of the big bang. They don't know what is going on either, but they sure do make money selling books to other people who don't know what is going on.

    You can fill up an entire thread with your notions as to what "caused" the big bang. You will not be able to reach any conclusions, and will still not know what is going on, just like everybody else on the planet.

    The more knowledgeable people know that they don't know what is going on. The less knowledgeable and the outright deluded think they know what is going on. But they don't.

    So you have two choices. You can recognize that you don't know what is going on. Or you can fail to recognise that fact that believe that you know what is going on. But no matter what, you won't really know what is going on.

    Next topic ?
    You say there is no "before" the big bang. I thought that the Big Bang Theory simply made no comment about any possible cause or "before" the event.
    You go on to say that theory breaks down, at the singularity, where infinities arise.
    Does this conflict, in any way, with some of your earlier posts where you seemed to state that infinity was well understood by mathematicians?

    You say that "the outright deluded think they know what is going on". One could argue that you almost appear to believe you know "what is going on" when you state categorically "there is no before, nothing caused it". In other words it was a random event and to even suggest there could be a cause is stupid.
    Lastly what questions will be answered by a theory of quantum gravity?
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  13. #12  
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    Quote Originally Posted by Halliday
    You say there is no "before" the big bang. I thought that the Big Bang Theory simply made no comment about any possible cause or "before" the event.
    You go on to say that theory breaks down, at the singularity, where infinities arise.
    Does this conflict, in any way, with some of your earlier posts where you seemed to state that infinity was well understood by mathematicians?
    There is no conflict.

    The big bang represents the beginning of spacetime, in essence the beginning of both space and time. It is prediction of general relativity based on the inferred structure of the spacetime manifold.

    The notion of the singularity of the big bang is a bit more subtle than "infinities". But in any case the understanding of the singularity associated with the big bang is not related to the characterization of "infinity" in mathematics, which is an entirely different subject.

    The notion of "infinity" in mathematics is described in the theory of cardinal and ordinal numbers. This has essentially nothing to do with the big bang.

    The big bang singularity is based on the notion of time-like geodesic incompleteness, a much more subtle subject. If you want to look into this subject, you might try reading The large-scale structure of spacetime by Hawking and Ellis or perhaps Spacetime and Singularities, An Introduction by Gregory Naber.

    Quote Originally Posted by Halliday
    You say that "the outright deluded think they know what is going on". One could argue that you almost appear to believe you know "what is going on" when you state categorically "there is no before, nothing caused it". In other words it was a random event and to even suggest there could be a cause is stupid.
    Within the context of general relativity, which is the basis for the prediction of the big bang, there is no meaning to "before" and hence there is no meaning to a "cause".

    It is not described as a random event. It is not really described as an event at all, because to have an event, in the sense that you seem to be using the word, would require a notion of "before".

    The analogy has been made that asking what happened before the big bang is like asking what is north of the the north pole.

    What is important to recognize is that the big bang was not some sort of explosion of matter within space. It was the creation of space itself, and the beginning of time itself.

    There is a pretty good discussion, with some useful pictures in The Road to Reality, A Complete Guide to the Laws of the Universe by Roger Penrose.
    (I think the title is a bit tongue-in-cheek.)

    Quote Originally Posted by Halliday
    Lastly what questions will be answered by a theory of quantum gravity?
    Nobody can answer this question until a theory of quantum gravity actually exists.

    What does seem to be the case is that general relativity breaks down in situations in which quantum effects are important, as with the big bang and in the interior of black holes (that is likely what the predicted singularities are telling us). Quantum theory breaks down when gravitational effects are important, as with the big bang and the interior of black holes.

    So, one might hope that a valid theory of quantum gravity would help to explain phenomena near the singularities predicted by general relativity for black holes and the big bang.
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