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Thread: Big bang and the laws of physics

  1. #1 Big bang and the laws of physics 
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    I am not a physicist but one of the fundamental laws of physics states that energy can not be created or destroyed, only changed. Yet for a big bang creation of the universe a vast amount of energy must have been created from absolutely nothing - nada. Do physicists therefore accept that the big bang violates normal laws of nature and is unnatural or supernatural by definition? I don't really understand how physicists rationalise a vast, spontaneous creation of energy and matter and keep it within the normal laws of nature.


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    There are three ways around this issue, as I understand it from my simple minded Earth scientist approach.

    1. The Big Bang originated from matter and energy that already existed. e.g. google branes, or big crunch.
    2. The laws of physics are the laws for this universe, they do not necessarily apply to what preceded this universe.
    3. The universe may be a rather large vacuum fluctuation (google that too) which will eventually have to be paid back.


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    We donít have a physics that describes the effect of gravity at the quantum level and the laws we do have don't apply. The eventual laws of quantum gravity will certainly describe the events of the Big Bang without any rationalization.

    According to Einstein, matter and energy are the same. Both have the property of mass. To move a mass against gravity to orbit takes energy. So gravity is basically negative energy. If you could add up all of the matter and energy in the universe along with the gravity of its mass, then the result may be zero. Alan Guth who came up with the theory of inflation, is pretty sure that you can get the whole universe from nothing because everything in the universe still has a sum of zero.
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    So by that reasoning energy wasn't created from nothing?
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    Quote Originally Posted by Arch2008
    We donít have a physics that describes the effect of gravity at the quantum level and the laws we do have don't apply. The eventual laws of quantum gravity will certainly describe the events of the Big Bang without any rationalization.

    According to Einstein, matter and energy are the same. Both have the property of mass. To move a mass against gravity to orbit takes energy. So gravity is basically negative energy. If you could add up all of the matter and energy in the universe along with the gravity of its mass, then the result may be zero. Alan Guth who came up with the theory of inflation, is pretty sure that you can get the whole universe from nothing because everything in the universe still has a sum of zero.
    I am sure this statement could be called an unscientific sound bite, but I have heard the universe being described (cannot remember the writer) as a "fluctuation around nothing".
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    Energy has mass (as does matter). Mass has the property of gravity. Gravity acts as negative energy. Energy and its negative energy counterpart of gravity can come from nothing because their sum may still be nothing. The actual event that physics cannot yet describe that triggered the Big Bang only used the energy you would get from about one single kilogram of mass in a space smaller than a proton and transpired in one ten million trillion trillion trillionth of a second. At this, the quantum level, things behave as though they are in two places at once, particles act like waves and waves like particles.
    http://en.wikipedia.org/wiki/Alan_Guth
    http://pages.towson.edu/zverev/universe/Universe.htm#1
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    Quote Originally Posted by Halliday
    I am sure this statement could be called an unscientific sound bite, but I have heard the universe being described (cannot remember the writer) as a "fluctuation around nothing".
    Please refer to my point 3 above.
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    Quote Originally Posted by Ophiolite
    Quote Originally Posted by Halliday
    I am sure this statement could be called an unscientific sound bite, but I have heard the universe being described (cannot remember the writer) as a "fluctuation around nothing".
    Please refer to my point 3 above.
    Just in case I failed to make this clear: when I posted I was not criticising your post or the post of Arch2008. I found both interesting.
    I was impressed when I first heard the phrase "a fluctuation around nothing" but was influenced (probably wrongly) when another writer (again cannot remember the name) mentioned the phrase and called it "a superficial sound bite".
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    Quote Originally Posted by Arch2008
    We donít have a physics that describes the effect of gravity at the quantum level and the laws we do have don't apply. The eventual laws of quantum gravity will certainly describe the events of the Big Bang without any rationalization.

    According to Einstein, matter and energy are the same. Both have the property of mass. To move a mass against gravity to orbit takes energy. So gravity is basically negative energy. If you could add up all of the matter and energy in the universe along with the gravity of its mass, then the result may be zero. Alan Guth who came up with the theory of inflation, is pretty sure that you can get the whole universe from nothing because everything in the universe still has a sum of zero.
    from that reaosoning wouldn't it mean that with the subatomic(they are subatomic right) particles preseding before the big bang happened would have negative and positive energy too i.e. you need a universe to make a universe meaning because nothing is 100% efficent also meaning the steady stable theory of the universe if used to explain wat was before the big bang is sort of correct also meaning that there are millions of universes all with negative and positive energy so that means that more and more universes are just poping up????
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    bradford28. I think the idea of the big bang is that you start off with a multiverse, a number of universes co-existing, and they have a set total amount of matter and energy. The creation of a new universe may be taking the matter and energy from a universe which has just collapsed (or whatever) so the overall totals still remains the same. It is just movement from A to B.
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    Quote Originally Posted by Arch2008
    Energy has mass

    It would explain a few things if it did, notably how photons can curve in space when passing a large gravitational source, like a star. It has been suggested that the mass of a photon would be below 10^-35 kg if it does have mass. It would also mean that the speed of light is not the ultimate speed, and that something that could be lighter could travel faster, though by very little. I believe this could be proved because then gravity would travel that bit faster than photons.
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    http://en.wikipedia.org/wiki/Photon
    A photon has momentum, not mass. Thatís why it travels at the speed of light, like gravity. A photon is the force carrier for electromagnetism. Energy does have mass, as Einstein showed a century ago.
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