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B Was the Big Bang a quantum mechanical vacuum fluctuation?

  1. May 8, 2018 #1
    It has been proposed by Edward P. Tryon that the Universe may be a large scale quantum mechanical vacuum fluctuation where positive mass-energy is balanced by negative gravitational potential energy, as a consequence of the early inflationary launch of the expansion of the Universe, in which these quantum fluctuations particles got amplified, which would explain how our Universe could have inflated from these particles. But what particle(s) exactly? What initial particle is being referred to here?

    It is known that light preceded matter, so bosonic energy, chronologically speaking, could have been the first elementary particle to give rise to all the other particles that formed from it later. The Big Bang theory is said to have started from one single point. If I’m understanding it correctly, this hypothesis referring to that 1 point as being only 1 particle. Of course, it seems more probable that the Universe started out with one particle, rather than a bunch of particles to start out with, but that does not mean that this hypothesis therefore has to be correct.

    When a photon is scattering with matter or antimatter, part of energy from the photon is given to matter/antimatter, and a new photon with smaller energy is created. A particle which received energy from photon is accelerated. It can be repeated over and over again, and from an initial 511 KeV photon after millions of such interactions, you will have millions of photons with very low energies (e.g. visible spectrum, then infrared).

    But wait a minute, a photon that preceded all other particles? To suggest that an electromagnetic particle such as the photon could have been the first particle before all the other particles, from which the strong and weak force came forth later, that has to be backed up with scientific facts, observations and maths. It has already been proven that the electroweak force once preceded electromagnetism and the weak force. Concerning the strong force, which is carried out between protons and neutrons, when for instance a neutron decays, electromagnetism does indeed “show up” (a neutron decays into proton, electron and antineutrino). Again, there seems to be electromagnetism involved. However, this does not mean that the strong force came after electromagnetism, and this hypothesis therefore has to be true. I’d like to know if anyone here could provide me with facts in favour of this hypothesis, or against this.

    The law of conservation of energy forbids new energy to be added (because energy can neither be created nor destroyed), so the suggestion that a boson, like the photon, could have pair produced two matter/antimatter particles (a gamma photon is able to create a pair of electron-positron must have at least 1.022 MeV energy) seems to be the only remaining option to explain the vast amount of matter and energy in the Universe we have today, because this conservation law has to be satisfied, since new energy could not have been generated/added, therefore the existing energy could only have been changed/divided. The question how this first bosonic energy could have been in existence in the first place is the domain of philosophy, not science, so I won’t make any suggestions about that mystery, I’m only trying to find out the chronology of the Big Bang, and what happened after that first initial particle. If this hypothesis is true (which I’m not so sure about yet), taking inverse Compton scattering in account (in which a charged particle transfers part of its energy to a photon), it’s not quite clear to me how to get from an electron/positron pair to, well, more than an electron/positron pair, because they can’t divide any further, can they?
     
    Last edited: May 8, 2018
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  3. May 8, 2018 #2

    phinds

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    Not by serious physicists it's not. The Big Bang Theory is a description of how the universe evolved from a hot dense plasma at the end of inflation up to where we are now. It is silent about how everything started. Theories that purport to describe what happened at t=0 (the mathematical singularity you get if you extrapolate time backwards) are speculative and not part of the Big Bang Theory.

    EDIT: by the way, this "big bang started as a single point in space" is probably THE most widely misstated fact in physics and has been debunked here on PF approximately 7,831 times. Pop science is entertainment, not science.
     
    Last edited: May 8, 2018
  4. May 8, 2018 #3
    That's why I said:
    Do I understand you correctly that starting out with more than 1 particle is more plausible?
     
  5. May 8, 2018 #4

    berkeman

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    7,832 when you include this thread... :biggrin:
     
  6. May 8, 2018 #5

    DaveC426913

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    No. Whatever t=0 was, it was very likely not a particle at all. Multiplying it doesn't help the plausibility.

    It was a very small, very dense, very hot region, with unknown properties, that expanded very rapidly.
     
  7. May 8, 2018 #6

    Bandersnatch

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    That's the first I hear of quantum fluctuation particles. Shouldn't that be just quantum fluctuations?
     
  8. May 8, 2018 #7

    phinds

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    Actually, it's possible that it was not small at all but rather was infinite in extent.

    Also, I'm not so sure about the "unknown properties". Weinberg wrote a whole book about it (The First Three Minutes)
     
  9. May 8, 2018 #8
    The big bang is supposed to start with a superhot plasma in which all particle species are represented equally, more or less. Inflation is the standard idea for what came before that; and before that, some kind of cosmological boundary condition or initial value.
     
  10. May 8, 2018 #9

    DaveC426913

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    from-a-certain-point-of-view.jpg


    We are talking about t=0. i.e. less than 10-43s.
     
  11. May 8, 2018 #10

    phinds

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    Fair enough
     
  12. May 9, 2018 #11
    Who said that?

    ...holds exactly only in a Universe with exact time translation symmetry. This seems not be the case in our Universe on largest scales (galaxy cluster and up).

    Start with https://en.wikipedia.org/wiki/Chronology_of_the_universe ?
     
  13. May 9, 2018 #12
    The first atoms formed 400,000 years after the Big Bang. if you start off with a hot Universe, and you let it cool down, you’ll predict that you wind up with about 74% hydrogen and about 24% helium (by mass), which is the initial composition of every star. Our sun right now consists of about 62% helium (because it's about 5 billion years old), but initially this was 24%. All elements, except hydrogen and helium, are made in a star. "If the Big Bang were to generate the right amount of helium and other light nuclei, then there must have been an era in the early history of our Universe in which light, not matter, made up most of the energy" (a quote from Dan Hooper from Fermilab).
    Are you saying that the law of conservation of energy is not a universal law? o_O
     
  14. May 9, 2018 #13
    "light made up most of the energy" is not the same as "light preceded matter".

    The former statement simply says that most of the energy was in the form of photons in early, hot periods. Which is hardly a surprise, given that blackbody emissivity is proportional to T^4.

    The latter says that there was a time where there was only light. No support for that.

    Yes.
     
  15. May 9, 2018 #14

    phinds

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    To expand on that a bit, conservation of energy is universally true LOCALLY. That is, everywhere in the universe energy is conserved on small scales (~ within glactic clusters) but over cosmological distances it is not.
     
  16. May 9, 2018 #15
    Has the creation or destruction of energy ever been observed?
     
  17. May 9, 2018 #16

    phinds

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    That's not the point. The point is you can't even DEFINE things like kinetic energy on cosmological scales

    http://www.preposterousuniverse.com/blog/2010/02/22/energy-is-not-conserved/

    EDIT: Oh, and by the way, yes. For example, red shifted light from distant objects has lost energy and it hasn't been converted into some other form, it just isn't conserved.
     
    Last edited: May 9, 2018
  18. May 9, 2018 #17
    Let's say we have a large region of space in our Universe with matter neatly packed in equal number of isolated containers with matter and antimatter.

    As Universe expands, the density of energy of this region will fall as a^3. (As is the case for any matter-dominated region).

    Now open these containers and let matter and antimatter react, converting most of it into EM radiation. As Universe expands, the density of energy of this region will fall as a^4 now.

    Obviously, the setup of this thought experiment can be extended to the entire Universe.

    Fishy, isn't it. Depending on what you do with the matter, you get different energy density in the future!

    In a flat, non-expanding spacetime (which is time-translation invariant), this would not be the case.
     
  19. May 9, 2018 #18
    I'm not quite following your example, could you please give another metaphor? I really would like to understand what you mean. Are you referring to dark energy?
    Are you sure it hasn't? The zero-energy Universe states that there's just as much gravitational potential energy as "normal" energy, the real, Standard Model energy. In other words, the "not stuff" is equal to "stuff".

    Not only objects can exert mass. Massless photons for instance are attracted to black holes, and black holes can't be made of matter, because a neutron star is the densest form of matter known (with masses between 1,4 and 3 Solar masses), in which the electrons have been driven into the nuclei by reverse beta decay. Black holes of course can have a much more mass than 3 Solar masses, so a black hole can't be an object (made of Standard Model "stuff") which is exerting mass to its surroundings, gravitational energy itself is a form of mass. We need dark matter for the same reason, because our "normal" Standard Model matter can't explain all the mass we measure.

    According to Einstein, mass can be converted into energy. Dark energy is responsible for the expansion of the Universe, and therefore for the stretching of spacetime, which changes the radiation from short wave to longer waves. So, "hasn't the redshifted long wavelength converted into some other form", as you're arguing @phinds ? This seems to me as a wrong conclusion, because you're measuring the normal matter, the "stuff" from the Standard Model, instead of taking in account gravitational potential energy, the "not stuff", which certainly can "have" mass.

    But of course, I could be wrong. I don't claim to be right because I'm not a professional physicist or anything, I'm only explaining how I'm interpreting it, which could be wrong, I can't deny that. I'm only asking questions on this forum because I'd like to understand the subject much better, so please correct me where I went off track. That would be much appreciated :smile:.
     
    Last edited: May 9, 2018
  20. May 9, 2018 #19
    I'm referring to EM radiation experiencing redshift, which adds yet another factor of a to the rate of decrease of energy density.
     
  21. May 9, 2018 #20

    phinds

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    No. I note that nikkon has now told you the same thing. Did you read the article by Carroll? You are arguing against established physics.
     
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