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Mathematical Proof That the Universe Could Come From Nothing

Posted by Soulskill on from the you-are-a-long-term-fluctuation dept.

TaleSlinger writes: One of the great theories of modern cosmology is that the universe began in a "Big Bang", but the mathematical mechanism by which this occurred has been lacking. Cosmologists at the Wuhan Institute have published a proof that the Big Bang could indeed have occurred spontaneously because of quantum fluctuations. "The new proof is based on a special set of solutions to a mathematical entity known as the Wheeler-DeWitt equation. In the first half of the 20th century, cosmologists struggled to combine the two pillars of modern physics— quantum mechanics and general relativity—in a way that reasonably described the universe. As far as they could tell, these theories were entirely at odds with each other.

At the heart of their thinking is Heisenberg's uncertainty principle. This allows a small empty space to come into existence probabilistically due to fluctuations in what physicists call the metastable false vacuum. When this happens, there are two possibilities. If this bubble of space does not expand rapidly, it disappears again almost instantly. But if the bubble can expand to a large enough size, then a universe is created in a way that is irreversible. The question is: does the Wheeler-DeWitt equation allow this? "We prove that once a small true vacuum bubble is created, it has the chance to expand exponentially," say the researchers.

5 of 429 comments (clear)

  1. Okay, but by 31415926535897 · · Score: 4, Informative

    1. Quantum fluctuations are not nothing, but I guess we have to sell headlines here
    2. Inflation Theory seems faster than "exponential" expansion. We're talking about a theory that went from the size of a singularity to something bigger than the visible universe in 10^-32 seconds. Exponential is quite pedestrian compared to what is theorized.

    1. Re:Okay, but by Immerman · · Score: 4, Informative

      1) Depends what you mean by nothing. by standard measures of "mass" or "energy" quantum fluctuations are pretty much nothing. In fact I'm pretty sure virtual particle pairs are *exactly* nothing if measured from a sufficient distance.
      2) Are you sure? I thought I had heard the growth rate referred to as exponential by cosmologists, though I couldn't swear it wasn't "science reporters" inserting fancy-sounding words they don't understand. After all in a scientific context "exponential" says nothing whatsoever about speed, it specifically refers to the shape of the growth curve: size = A^(Bt). If B is negative that can actually represent an infinitely slowing convergence to zero, as in nuclear radioactivity. And if A and/or B are large enough an exponential growth can be as insanely fast as you like.

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      --- Most topics have many sides worth arguing, allow me to take one opposite you.
  2. Re:Something, not nothing by Anonymous Coward · · Score: 2, Informative

    From the summary:

    This allows a small empty space to come into existence probabilistically due to fluctuations in what physicists call the metastable false vacuum.

    and

    "We prove that once a small true vacuum bubble is created, it has the chance to expand exponentially," say the researchers.

    So, yes, this is a model by which a hyper-infinite sea of not-quite-nothing can have vastly expansive bubbles of actually-nothing. If you're wondering how this relates to the origin of our universe, it doesn't. The lopsided matter and energy of our universe indicates that it was not the result of a singular true-vacuum by any measure. If they had some model that allowed the metastable false vacuum to spawn vastly expanding non-vacuum bubble pairs of opposite matter/energy profiles, then that might be relevant to our reality.

  3. Re:Nothing? by drerwk · · Score: 4, Informative

    As long as there's no faster-than-light travel, "X happens before Y" is an invariant - it's true in all reference frames.

    No. http://math.ucr.edu/home/baez/... and for the longer version http://en.wikipedia.org/wiki/L.... In these examples, the doors either close at the same time for the observer stationary with respect to the barn, or at different times for the observer running with the pole.

  4. Re:Nothing? by Guy+Harris · · Score: 3, Informative

    As long as there's no faster-than-light travel, "X happens before Y" is an invariant - it's true in all reference frames.

    No. http://math.ucr.edu/home/baez/... and for the longer version http://en.wikipedia.org/wiki/L.... In these examples, the doors either close at the same time for the observer stationary with respect to the barn, or at different times for the observer running with the pole.

    OK, sorry, should have said ""X doesn't happen after Y" is an invariant" (there don't exist reference frames such that X happens before Y in one frame and X happens after Y in another frame).