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Creating matter from nothing

  1. Mar 9, 2014 #1
    Alright, I'm well aware of the law that energy/matter cannot be created nor destroyed, but:

    Considering that universe began at a certain point in time and didn't exist prior to that, doesn't there HAVE to be a mechanism that creates energy/matter?

    Without some way of creating something from nothing, the energy that created the universe in the initial big bang/bounce would never have began to exist.

  2. jcsd
  3. Mar 9, 2014 #2


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    No. There is no point in time where energy and matter were created. This looks unintuitive, but the laws of physics are laws in our universe, not laws how universes could start.

    Some inflation theories propose a universe where the total energy does not change for the big bang, as some additional fields contribute to the total energy.
  4. Mar 9, 2014 #3
    Consider three things.

    1st) The energy conservation law states that energy of the universe should be the same for any two instants of time along its history (so to speak). Prior to the Big Bang isn't an instant of time along the universe's history (just as north of the north pole isn't a place on Earth)

    2nd) The total energy of the universe might very well be zero

    3rd) The concept of energy conservation does not readily generalize to cosmology.
  5. Mar 9, 2014 #4


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    To expand just a bit on dauto's 3rd point, consider this:

    You can look at a cosmologically distant object and see that it is moving a speed X relative to the Earth and has a mass M, and so you can say that it took an amount of energy E to get it going that fast. But that doesn't have any meaning at all in physics because you can equally well say that the object is ACTUALLY moving at speed X2, not X, by using a different reference frame and therefore it took an amount of energy E2 to get it moving to that speed. Since you can't even define the amount of energy that went into getting the object "moving" (and it is NOT moving if you chose the right reference frame) how can you say that energy is conserved?

    So energy conservation is valid at local scales but not cosmological scales. Just don't ask me to define where "local" transitions to "cosmological" :smile:

    MacElliott, I wrote a response to your post about singularities but by the time I tried to post it, the thread had been erased. It seems that you are simply posting made-up physics based on misunderstandings you have. You should study some real physics and learn the basics before you continue.
    Last edited: Mar 9, 2014
  6. Mar 9, 2014 #5
    While I definitely love the analogy there, one could argue that the definition of what "north" truly is just became redefined once it reached its absolute maximum.

    I remember I wrote something way back when that asked what could possibly happen when infinity is reached by using a circle and gradually coloring with radii until it was all black as an analogy. Since there was nowhere for me to draw another radius, one of two things had to be done in order for more possibilities to be generated: a) a new dimension could be added and one could then repeat the process using 2d circles to fill a sphere, or b) one could start erasing the radii one by one and the process would become its opposite. (The other thing that I realized is that the value of infinity is relevant to its paramaters.)

    Either possibility could be applied to the pre-big bang universe/time in that a) the parameters of what "time" truly is could simply be redefined, and since our definition of time is relevant to the processes we see in the universe, one would HAVE to redefine time to something not reliant on units based off of matter travelling distances and b) if we assume the big bounce model is correct, one could argue that space/nothingness reached its maximum value and a new parameter had to be introduced (matter)
    The same could be said about energy, in that since the energy in our universe is massed, our understanding of it is limited to massed energy, which could (theoretically) not have existed prior to the big bang.

    As for your other two points, could you please elaborate? I'm fairly intrigued
  7. Mar 9, 2014 #6
    I have actually studied physics extensively and I figured that this site would be the place to put my ideas up against scrutiny considering none of my peers or teachers have any knowledge or interest beyond g12 physics.. so my question to you is that what do you mean by "made up?" (lol) and where should I post ideas to see what other people think?
    Last edited: Mar 9, 2014
  8. Mar 9, 2014 #7


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    This blog entry of Sean Carroll's does that to an extent:

    This page discusses energy conservation in General Relativity in more detail:

    The idea of zero energy universe is championed by some, especially by Lawrence Krauss(you can find his talks on the subject on youtube), but as you could see in the first link, others see it as muddling the issue.

    Not here. The rules of the forums, which you have agreed on upon joining, prohibit you from posting personal theories. The purpose of PF is to help people learn established science only.
  9. Mar 9, 2014 #8


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    No, the place to propose new scientific ideas is the peer reviewed journals and scientific conferences. This site is the place to discuss and learn about modern science.

    If you wish to continue this discussion then please post an acceptable reference that you would like to discuss.
  10. Mar 9, 2014 #9


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    I assume you got a warning from a moderator when they deleted your thread. Surely they mentioned that, as bandersnatch and dalespam have said, this is not the place for unsupported (and particularly unsupportable) theories, it's a place for real science. Based on your posts, I'm surprised to hear that you have studied physics extensively.
  11. Mar 9, 2014 #10
    I did get such a warning, and I admit that I misinterpreted the point of this site. However, I'm sure you're aware that you eventually reach a point in physics where it stops being science and becomes more of a religion, and quite frankly every (philosophized) idea started out as just a theory until it was proven and became "real" science. And granted that I didn't realize this wasn't the place for such ideas, it doesn't justify immediately dismissing ideas simply because they haven't been proven/disproven yet.
  12. Mar 9, 2014 #11


    Staff: Mentor

    It isn't about dismissing ideas, it is about discussing them in the correct place. New ideas belong in the peer-reviewed literature and scientific conferences where they can get the proper attention they deserve. You don't write a novel and then publish it in the obituary section of your local news paper.
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