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Subatomic Particles From Nothing?

  1. Jul 18, 2013 #1

    Nugso

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    Hello everyone. I once read an article saying subatomic particles can exist from nothing in a vacuumed space( or something like that). Is that even possible? Or does the energy vacuumed space has turn into mass/matter, hence we thing it exists from nothing?
     
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  3. Jul 18, 2013 #2

    kith

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    Statements like that are sloppy popularizations of quantum field theory. It is misleading to talk about "nothing" here because these effects occur because of the presence of quantum fields.
     
  4. Jul 18, 2013 #3

    hilbert2

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    A simplified explanation is that according to energy-time uncertainty relation, a virtual particle-antiparticle pair of total energy ΔE can be created in vacuum for a time interval of approximately [itex]\Delta t = \frac{\hbar}{\Delta E}[/itex]
     
  5. Jul 18, 2013 #4

    Nugso

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    Thanks for the replies kith, hilbert. But I still want to ask a question regarding it;

    @hilbert2

    It can be created in vacuum. But doesn't vacuum have an enegry?

    @kith

    I don't get the last sentence. Would you please explain?
     
  6. Jul 18, 2013 #5

    kith

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    You asked if particles can be created from nothing. I said no because all statements claiming so require quantum fields and quantum fields are not nothing.
     
  7. Jul 18, 2013 #6

    Nugso

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    Oh, so those so-called subatomic particles exist within the realm of quantum field.
     
  8. Jul 18, 2013 #7

    hilbert2

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    Vacuum is a state where all quantum fields are in their ground state (state of minimum energy). In principle, the fields have an infinite number of "Fourier modes", all of which have a finite zero-point energy even in the ground state. Therefore, vacuum has an "infinite energy", but this zero-point energy is not a quantity that can be measured, and therefore it can be ignored.
     
  9. Jul 18, 2013 #8

    Nugso

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    I see now! Do you also know that the vacuum state before big bang and the vacuum state we see now are different from each other?
     
  10. Jul 18, 2013 #9

    kith

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    Yes. On the most fundamental level, all elementary particles are excitations of their corresponding quantum fields.
     
  11. Jul 18, 2013 #10

    Nugatory

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    No such thing
     
  12. Jul 18, 2013 #11

    Nugso

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    I see where you're coming from but I think something had to happen before Big Bang.(though time didn't exist before Big Bang)
     
  13. Jul 18, 2013 #12

    Vanadium 50

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    We can't discuss "I once read somewhere". If the OP has a link or a reference, we can reopen this thread. Otherwise, we have to guess at what we are trying to explain.
     
  14. Jul 18, 2013 #13

    Nugso

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    Krauss's A universe from Nothing. I don't think I'm allowed to copypasta though.
     
  15. Jul 23, 2013 #14
    Opinion: and from a doco (David Suzuki I think) he talks about 'nothing' and 'nothing', one is what we think of nothing in our known universe, but that nothing contains all sorts of things like, light, energy, gravity, dimensions, and time.

    And there is the other nothing which is a compete absence of everything, no space, no time, no light, no energy.
    By that definition I would think there is nothing in our Universe that is nothing.
     
  16. Jul 23, 2013 #15

    bhobba

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    Mind numbing isn't it.

    One modern view is it started out from what is known as the false vacuum:
    http://en.wikipedia.org/wiki/False_vacuum

    For an interesting discussion check out:


    Been meaning to watch it for a while now so guess what I am going to do for the next hour or two.

    Thanks
    Bill
     
    Last edited by a moderator: Sep 25, 2014
  17. Jul 23, 2013 #16

    Nugso

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    @Darryl, that's why I was trying to figure out what happened before. Thanks!

    @bhobba, Thanks for the link and the video. There're still some doubts on my mind about the multiverse theory. Hope the video will answer them.
     
  18. Jul 23, 2013 #17
    It seems superposition of states are fundamental and the known macroscopic concepts from experience(matter, time, space, life...) arise via decoherence and observation/world-splitting. In this fully consistent with all qm experiments view, there is no before and no after at the most fundamental level. There was an attempt at keeping objective reality fundamental in the Bohmian interpretation but it's no longer fully consistent as superpositions have been indirectly observed/employed and will continue to be utilized in the computing of tomorrow and in that interpretation superpositions were not part of the theory. One of the top physicists once said that if a question seems interesting, it likely has an answer(although per the rules your question on events 'before' the BB falls outside the scope of the forums).
     
  19. Jul 23, 2013 #18
    Well quite honestly speaking "before the Big Bang" kinda falls out of everything not only on this forums but on this world...
    As till this point physics and the level of knowledge has showed us that we have no actual physical way of knowing before the beginning or in other words the BB.So I believe that it will always be left as a matter of what is most believable and scientifically accurate scenario.

    About the nothing nothing , well the one which is the real nothing I believe we have nothing to say about that.One just simply can't say something about nothing.This is actually a philosophical matter.

    You gotta have faith to believe in nothing... :)
     
  20. Jul 24, 2013 #19
    One possibility I watched on another documentary it think the idea was proposed by Penrose or at least explained by him, considered what happens AFTER the Universe, not before it.

    If you consider that everything will eventually degrade to photons, when that occurs you have a universe with nothing but photons, you have no gravity, no dimensions, no distance, and no time.
    Sounds a lot like it could have been before the BB.

    the moment the last bit of matter ceases to exist, the size of the universe becomes zero, time stops, or starts as the new universe is BB'ed into existence.

    That would seem to me that there was time before the BB, and it was the 'stopping of time' that caused the BB to happen at the instant time stopped before the BB, it might be a fundamental that time has to past. If it tries to stop a BB will occur to make it continue !

    Sounds like as good a theory to me as any other ..
     
  21. Jul 25, 2013 #20

    Nugso

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    Thanks, but how could that be possible? If there are going to be protonos can't we as well say that there're going to be dimension(distance between protons that is), gravitiy(the force acting at each other and the force that curves the space and time, though very weak force)?
     
  22. Jul 25, 2013 #21

    Nugso

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    And I hope we'll someday figure out what happened before the BB. :tongue:
     
  23. Jul 26, 2013 #22
    only theoretically and even then not with a 100% certainty.
     
  24. Jul 26, 2013 #23

    ZapperZ

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    I'm a bit disappointed with the responses in this thread. It seems that whenever a question like this occurs, the FIRST thing that often gets brought up is the "big bang" or how it came into being due to such vacuum fluctuation. I know the OP later on brought up Krauss's book as the "source", but really, we need to keep in mind two things here:

    1. vacuum fluctuation came out of the concept of quantum criticality, which is a consequence of quantum field theory.

    2. there are already strong evidence of quantum criticality without having to invoke exotic, still debatable, and still highly unverified idea of "what happened right at or before the Big Bang"!

    Quantum criticality, and the existence of quantum critical point, has some of the strongest evidence out of condensed matter. In fact, I can tell you that this might easily be present in the behavior of electrons in metals! How much more "common" and "pedestrian" than that?

    In responding to a question such as this, established first the validity of the idea via results that we already know. Show that this phenomenon is well-known, and that the application of the principle is the only known explanation for these well-established observations. Then show that if this principle works there, then there is a good possibility that it should also work in more "exotic" situations, and that's where someone such as Krauss might apply the concept to the possible beginning of our universe. Jumping straight into the Big Bang gives the impression that this idea has no other evidence to support it, which is patently false! It isn't something that was plucked out of thin air as a crutch to explain the beginning of our universe. It is a concept that has already been known to work elsewhere, and that needs to be established first and foremost!

    Zz.
     
  25. Jul 26, 2013 #24

    Nugso

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    Hello Zz. Sorry for the late reply. I've had hard time translating your post, thanks to my English. :shy: I still don't understand "How much more "common" and "pedestrian" than that?", though.



    I'd like to apologize to all those who replied. My apologizes are due to my sidetracking the thread.( From subatomic particles to the BB theory)


    Thanks for the article. Reading the whole of it. Will be asking questions as soon as I'm done reading.( Language of it seems sort of difficult to me, would take a lot of time)
     
  26. Jul 26, 2013 #25

    Nugso

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    Well, you know there's this nice quote; " Quantum theory is a world of possibilities, nothing is certain." :biggrin:
     
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