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Vacuum fluctuations and matter

  1. Feb 14, 2010 #1
    Does the process of pair production mean that the quantum vaccuum fluctuations can produce atoms(given enough time) as the following quote on wikipedia seems to suggest? Has it been experimentally confirmed that atoms can be formed in the seething with virtual particles zero-point energy state of the quantum field(ground state)?

    "It is sometimes suggested that pair production can be used to explain the origin of matter in the universe. In models of the Big Bang, it is suggested that vacuum fluctuations, or virtual particles, briefly appear.[9] Then, due to effects such as CP-violation, an imbalance between the number of virtual particles and antiparticles is created, leaving a surfeit of particles, thus accounting for the visible matter in the universe."

    http://en.wikipedia.org/wiki/Virtual_particle" [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Feb 14, 2010 #2
    In theory, perhaps...but not experimentally verified according to a recent thread here...can't find it right now..... Even Hawking radiation based pair production has not been verified....
    right now I believe there is no generally accepted origin of the big bang...lots of equations once it gets started but the origin has been a conundrum.

    Either our universe was an almost one of a kind special case, or there are an infinite number of fluctuations every moment guaranteeing an infinite number of universes..in which case we once again seem to be real lucky....

    We do see pair production evidence experimentally in high energy physics....but I guess it's not been convincingly extended to zero energy vacuum conditions.
    Last edited: Feb 14, 2010
  4. Feb 15, 2010 #3
    Fluctuations in a Primordial Vacuum in some cosmological theories leads to a 'big bang'. The vacuum from which that inflationary event occurs however does not share a vacuum. There is also Brane Cosmology, and far more. These are all as of now, pure theory or conjecture. Our actual OBSERVATIONS are far more limited.

    Hawking Radiation is a singular (it would seem) event in which a virtual pair only becomes 'real' in the sense that the lost photon can be seen as part of the worldline of the 'escaping' photon.

    Otherwise Naty1 has answered your question.
  5. Feb 15, 2010 #4
    Thanks for the answers. I have a related question that i hope makes sense:
    Quantum fluctuations produce short-lived virtual particles that come and go at around 10^-38sec. Those are the same virtual particles that give most of the mass found in the nucleus of atoms, right? My suggestion was, and sorry if it's incorrect - since unmeasured atoms aren't really physical objects, as seen in the c60 double-slit experiment, so would it be unreasoable to suppose that atoms(if we view them as measured states or rather the properties/observables we measure and label 'atoms') really only exist as a representation of the dynamics of the ground state of the qunatum field(Wheeler's 'quantum foam',where space and time break down and stop having any physical meaning)? Quanta can 'tunnel' through space and reappear at another location as if they didn't physically go through that space, so is it possible that electrons used in electron microscopes disappear(flow) in the quantum vaccuum and reappear out of the quantum vaccuum at another 'location', because space and time are only macroscopic phenomena and 'location' denotes only the measured states of relational systems? In particle accelerators electrons are often accelerated to more than 99.99% the speed of light and they gain tremendous amounts of relativistic mass in our frame of reference and smashing them generates many new short-lived particles whose total mass is thousands times the mass of the unaccelerated electron. This added mass comes from the quantum vaccuum via virtual particles, right?(that's the only way we know of something coming out of nothing, though the ground state of the field is probably not the best example of 'nothing' as its Hamiltonian is never zero)? How much of a role does the quantum vaccuum play in matter and are future GUT's(LQG and ST) showing any insights in this direction? Could the proposed idea of future Energy from the Vacuum of Space(almost something out of nothing), be alluding to matter being much more closely related to the quantum vacuum of space(or even a result thereof)?

    PS> Zeilinger's experiment with teleporting atoms was instantaneous, i.e. it didn't take any time and those atoms didn't traverse any distance, right? So would it be reasonable to assume that since it isn't possible to ascertain any trajectory, the teleported atom plunged into the quantum vacuum of space and reappeared 'somewhere' else(half a mile, if i am not mistaken)? Would it be an overstatement to say the quantum vacuum is probably the last frontier of science that could resolve many conceptual problems in foundational physics?
    Last edited: Feb 15, 2010
  6. Feb 15, 2010 #5
    No. In theory that would be the Higgs Mechanism mediated by the Higgs boson.

    Experiments such as that show wave-particle duality seems to exist at least for molecules of that size or larger. What you make of that (or if you even believe that) might depend on whether you adhere to the The Copenhagen Interpreation (TCI), de Broglie-Bohm with Many Worlds, etc...

    You're struggling with the dual issues of locality/non-locality and realism. Whatever you've been reading is on the science fiction end of things however. I suggest some reading into just what QM is, so that you don't lose quite so much in the translation from the math to language.
  7. Feb 15, 2010 #6


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    I don't understand the question, but I can say that the 'idea' of getting energy from the vacuum (which you have capitalised for some reason) is espoused by some very dodgy people and has no basis in physics. To get energy that can actually do some work for you, you need an energy gradient of some kind to start with. Random fluctuations don't provide this.

    One thing the laws of physics tells us is that there is no free lunch.

    In fact you might find yourself in hot water for even mentioning "Energy from the Vacuum of Space".:wink:

    No one has teleported matter. Only a quantum state. Read the reports again. You're off beam with this vacuum idea.
  8. Feb 15, 2010 #7
    These guys from California Institute of Physics and Astrophysics seem to be doing active research on this topic:

    See Zero-Point Energy on:


    In fact, it looks as though it's their primary target.

    Yes, i must have misread(misremembered) Zeilnger. His quote was:

    "Scientists might be able to achieve teleportation between atoms within a few years and molecules within a decade or so, Zeilinger said."

    Einstein said it couldn’t be done
    But it was: Particles of light shift physical characteristics


    I think Zeilinger is one of the titans of quantum physics and probably the most knowledgeable person on quantum teleportation on the planet today.

    Didn't the experimentally-verified Casimir effect already prove that the vacuum of space is not nothing?
    Last edited: Feb 15, 2010
  9. Feb 15, 2010 #8

    But calculations from QCD seem to suggest otherwise, i.e. most of the mass comes from virtual gluons and virtual quarks:

    "At Long Last, Physicists Calculate the Proton's Mass"


    "...physicists from France, Germany, and Hungary who performed the new calculations. Ninety-five percent of the mass of a nucleon originates from these virtual particles."
    Last edited: Feb 15, 2010
  10. Feb 15, 2010 #9


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    Hi Georg,

    the Calphysics Institute is a front for the renowned eccentric Haisch and his cohorts Puthoff and Rueda. Not all their work is whacky but the ZPF energy extraction is. I just read through their latest offering by Garret Moddel and it's nonsense. It's impossible to extract energy from the Casimir plates. The energy deficit that exists between the plates is exactly balanced by the potential energy in the material that keeps the plates apart. Did you see the drawing of the device to extract energy. What a laugh. They have not produced so much as a picojoule of useable energy.

    So what ? What has this got to do with the vacuum ? I bet you $1 Zeilinger thinks Haisch's idea are rot.

    It is nothing on average. The existence of the Casimir force would not be enough to treat the ZPF as a free source of energy.

    You just seem to be picking up random headlines and using them to justify fantasy - even when they have no relevance. For instance,

    Virtual particles are just a particle physicists way of describing the very strong binding energy that holds nucleons together. It has no bearing on 'ZPF energy'.
    Last edited: Feb 15, 2010
  11. Feb 15, 2010 #10


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    I meant to include this quote from the end of Moddel's paper

    So, he writes most it off. I take my hat off to him. It looks like those guys are pulling out of the ZPF nonsense.
  12. Feb 15, 2010 #11
    Hi Mentz,

    Would you say what i said in the quote below is false, as it relates to the point being discussed?

  13. Feb 15, 2010 #12

    So they are not the virtual particles that produce the experimentally-verified Casimir effect? They can't be purely mathematical if they can exert physical force, right? Are you saying there two kinds of virtual particles - mathematical and real ones?
  14. Feb 15, 2010 #13


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    Yes, it is false. The added mass comes from the kinetic energy of the accelerated electrons, which came from doing work on the electrons to accelerate them to greater than 0.9999c. In short, real energy was expended in order to produce the particles.

    Moderator's note:
    Georg, your questions have been answered in the negative repeatedly in this thread. If there isn't any progression or learning going on here, the thread will be locked.
  15. Feb 15, 2010 #14


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    if you're in learning mode - virtual particles are tricky. They are mathematical constructs but they represent real energy or momentum.

    The Casimir effect is produced by cancellation of electromagnetic ( and maybe other ) vacuum modes ( ie wavelengths ) between the conducting plates. The argument is that the region between the plates has a different vacuum because of this. The oscillatory Casimir energy extraction reported by Moddel can't work. Someone thought it could but they added up the energy incorrectly. Moddel dismisses it on 'thermodynamic grounds' which is just to say 'there's no useable energy there'.
  16. Feb 15, 2010 #15


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    Why Moddel and Haisch's Casimir 'pump' won't work.

    Details of the device are given in Moddels paper arXiv:0910.5893 (2009)

    A gas is passed through a Casimir cavity. The device relies on the 'spin-down' of electron orbitals which causes the atoms in the cavity to radiate. The radiated energy is caught by absorbers lining the cavity.

    1. There's no evidence that atoms will radiate in a Casimir cavity. Since stimulated emission in mode k depends on the number of quanta of mode k in the field, it's less likely they'll emit in the cavity ! The only effect of the vacuum on electon energy levels seems to be the Lamb effect, not emission.

    2. Let's pretend the atoms emit. The gas of atoms will then cool. This lowers the temperature in the cavity. When the radiated photons are absorbed, they raise the temperature of the lining.

    This is clearly violating thermodynamic principles, because without doing any work, they are getting heat to flow from a colder to a hotter body.
    Last edited: Feb 15, 2010
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